text:
The Twin Craters, locally known as Los Gemelos, are two wide pits on the Santa Cruz Island. They were formed through magma chambers collapsing following a volcanic uprising, lava hardened on the outside, but on the inside it kept flowing. You can walk on an enjoyable trail through a gorgeous Scalesia Forest up to the rim of the craters. At the top you'll be met by an extraordinary view of the lush green forest scenery. You can spot birds everywhere, like Darwin's finches, vermilion flycatchers, Galapagos doves and short-eared owls.
Disembarkation: Dry Landing
Darwin’s Finches, Galapagos Barn Owl, Galapagos Dove, Galapagos Mockingbird, Galapagos Petrel, Galapagos Short-eared Owl, Vermilion Flycatcher

domain: travel


text:
Setting the standard for Spanish food on the West Coast since 1984.
OUR HISTORY: Born in Seville and raised in Barcelona, Jose Luis Relinque moved to California at the age of twenty. By the age of thirty, the charismatic, self-taught young chef opened his first restaurant – the ground breaking and critically-acclaimed Spanish Restaurante Iberia in Portola Valley, near the heart of Silicon Valley.
After sixteen years in Portola Valley, Iberia moved to a new home in Menlo Park in late August 2000. The new restaurant features a glorious patio shaded by an ancient oak, a cozy bar de tapas with a wood-burning fireplace, a colorful and romantic dining room, a wood-paneled banquet room with private patio, and the wine library. Iberia’s second-story glass-fronted wine library won the prestigious Wine Spectator Magazine’s Award of Excellence; the collection focuses on Spanish and California red wines.
In the Spring of 2001 Iberia opened The Rock of Gibraltar Comestibles, a retail food store offering all of Iberias’s favorite dishes “to go”, as well as the largest resource for imported Spanish food products in Northern California. The Rock also has cooking programs that are hands-on and allows students free run of Iberia’s kitchens. Conveniently, The Rock is located just next door to Iberia.

domain: food


text: Rare gem, private keyed elevator access to a 2300 SF Penthouse with panoramic views of the ocean, Sobe, Open the glass wall out onto a private 3000 SF terrace with incredible views ideal for relaxing or spending time with your friends. A beautifully furnished open loft with tastefully appointed, eclectic art and furniture, a gourmet kitchen with stainless counter tops. The Master BR has nautical style large sunken style bath. Hurricane windows, private one car garage, plus two additional parking spots in the general lot, gym on the ground floor along with swimming pool. Minutes walk to the beach and an endless selection of diverse restaurant and entertainment options including the Jackie Gleason Theater and the Bass Museum of art. 15 minutes to/from Miami Int. airport.

domain: artistic


The Littelfuse SSAC LLC1 Series is a single probe conductive liquid level control designed for OEM equipment and commercial appliances. This unit may be ordered with selectable or fixed fill or drain operation. A time delay (1-60s) prevents rapid cycling of the output relay. On adjustable units, the sensitivity adjustment allows accurate level sensing while ignoring foaming agents and floating debris. Isolated AC voltage is provided at the probe to prevent electrolysis. A trickle current of less than 1mA determines the presence or absence of liquid between the probe and common. The LLC1 Series printed circuit board is conformal coated to resist moisture and corrosion.


text:
I felt like it had been a while since I last got out to the range, so me and a few pals decided last minute to head out there after work on a Tuesday night.
I never get tired of going to this range, the steel targets are awesome and I could literally spend hours there if ammo was free, lol!
Alex with his new bike.
Resident humming bird.
Don testing out his new Stag 10 in 6.5cm. He managed some pretty decent groups with some really cheap ammo.
For the fireballs, all we did was film it and screen cap instances where there was fire.
Mild steel is absolutely useless when it comes to anything beyond 9mm, lol! We set this thing up at about 100m and just obliterated it.

domain: hobby


text:
Caste Based Discrimination Prevention Cell (CBDPC)
The Ministry of Human Resource & Development, Government of India, the Department of Higher Education, New Delhi and University Grants Commission are continuously monitoring the prevention of caste based discrimination in Higher Educational institutions. The college ensures that no officials / faculty members/ students indulge in any kind of discrimination against any community or category of students. CASTE BASED DISCRIMINATION PREVENTION CELL (CBDPC) is constituted in the college to prevent and solve issues of caste based discrimination. The cell aims to ensure that all students are treated as equal and attempts to ensure equity and equal opportunity to the students as a whole and bring in social inclusion. It helps to create a congenial atmosphere in the campus and for the growth of healthy interpersonal relationship among the students coming from diverse socio-cultural backgrounds. It seeks to sensitize the college on the problems of less privileged students and ensures that no student is left behind the teaching process. CBDPC aims to ensure that no student is discriminated in the name of caste and provides a platform to address their grievances frankly and thus to mitigate the diversity in the campus.
Functions of the cell
Encouraging the SC/ST students to express their grievances frankly without any fear of being victimised
To ensure that the grievances are registered and acknowledged promptly
To enquire into the grievances and make recommendations
To ensure prompt redressal of grievances.
To deal with every grievance in a fair manner
To recommend appropriate action if the complaint is found to be valid.
The cell comprises of the Principal of the college as the chairperson and senior faculties as members. If students belonging to SC/ST category have any complaints, they can lodge the complaints to the Tutor in charge, HODs or any member of CBDPC through the form given below.
Co-Ordinator - Dr. Sandhya Suresh
Members - Ms. Jayalekshmi (English)
- Mr. Shibu T(History)
- Dr. Renjini (Chemistry)
- Ms. Dhanya (Botany)
- Dr. Remya R(Malayalam)
- Ms. Reshmi S(Physics)
- Ms. Aswathy. S M (English)
Submit your complaints related to caste descrimination here:
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domain: sociology


Chris Pronger of the Philadelphia Flyers in the Stanley Cup playoffs.
Photograph by: File, Getty
CHICAGO — Listen to Chris Pronger field questions about Chicago Blackhawks’ mammoth winger Dustin Byfuglien, and you get pretty much the whole picture.
“He scored three game-winners in the last series, all from the slot, so . . .,” someone began.
“Congratulations,” Pronger cut in.
But . . . surely a guy as big as the 257-pound Byfuglien presents problems.
“Sure,’’ said the Philadelphia Flyers’ 35-year-old defenceman. “John LeClair was pretty big. I could go down the list of guys who were pretty big in this league. If you want me to break down my credentials, I’ll do that for you. But maybe we’ll just wait for the games and see what’s going to happen. How about that?’’
Sarcastic. Arrogant. And headed for the Hall of Fame, whenever he decides to call it quits, though right now, it’s hard to believe that a man who has led three different teams to Stanley Cup finals in his 30s is anywhere near the end of the line.
The attitude, though, is part and parcel of the Pronger Factor, which completely transformed the 2006 Edmonton Oilers, pushed the 2007 Anaheim Ducks over the top and now has brought a fractious, 18th-place overall Flyers outfit, complete with a mid-season coaching change, to within four wins of its first championship in 35 years.
Each of Pronger’s three finals has come in his first year with a new team. Maybe there’s a pattern here.
“Oh, totally, he’s arrogant,” agreed Craig Simpson, the former Edmonton star-turned-assistant coach and now Hockey Night in Canada analyst, who was on Craig MacTavish’s Oiler staff the year Pronger brought life back to a stagnant franchise. “I don’t think you could play that sort of overwhelming ’I’ll take care of things’ role if you don’t feel that way. He’s one part of the puzzle that’s constant — a guy who gobbles up minutes, and plays against the best players every night, who allows you to get your matchup and win it most times.
“He’s got such a strong personality, as a coach or teammate you’re always balancing the push-back. It’s the elephant in the room a lot of times, but on a good team with confident guys around him, I think it’s a component you can handle.
“I don’t know if this is appropriate, but the greatest line from Muck (former Edmonton coach John Muckler) was when we started to become not a great team, but everyone was going, ‘Yeah, but a great bunch of guys. Everyone works hard, good guys.’ Muck goes: ‘Well, maybe it’s time we got some a—holes who can play.’
“And maybe that’s what Pronger brings. He’s an a—hole who can play.”
And play, and play, and play — basically half of every game; 30 minutes of minimal stress for a head coach, because not many bad things happen during a Chris Pronger shift, unless they happen to the other team.
“I think he’s got to be regarded as one of the best D-men of all time,” said Blackhawks forward Patrick Sharp. “He’s won Stanley Cups, he’s won Olympic gold medals, he’s been dominant in the old NHL and then, once the rules changed, he was still able to find a way to be on top of his game.
“I’ve played him a bunch in my career. He can play physical and be dirty out there, which everyone likes as long as you’re not playing against him. And he’s got such a long reach and he’s smart, he never really panics — he’s got so much poise under pressure.”
Under pressure is where the Hawks would love to put the 6-6, 215-pound veteran, but it’s not as easy as it sounds. Maybe it’s the air up there, or the view, but Pronger sees the ice better than most and has a sixth sense about the space around him.
He also has a mean streak that manifests itself more than occasionally, as his litany of NHL suspensions will attest, including two in the late stages of the Ducks’ Stanley Cup run — one for trying to plant Detroit’s Tomas Holmstrom through the glass, and again in the final for a concussion-causing elbow to the head of Ottawa’s Dean McAmmond.
“There’s a fine line when you’re a six-foot-six guy,” Simpson said, in Pronger’s defence.
“On the ice, you’ve gotta give him some rope. Rarely does he do something so stupid that it costs you a game. He’s pretty good at picking his spots. He might get a really bad penalty, but you’re probably down by three at that point, and sure, it’s ‘let’s live to fight another day’ but he’s just letting you know it’s going to be a hard fight. I don’t remember him, at critical times, losing his mind.”
Like a lot of the very best hockey players, Pronger puts up a pretty good wall when it comes to talking about himself. It’s not from lack of ego, he just doesn’t like to advertise.
Though he wouldn’t characterize his three Cup appearances with three teams in the past five springtimes as coincidence, he wasn’t taking credit.
“Well, starting with Edmonton, they hadn’t made the playoffs a whole lot over the five or six years before I got there, and when I got there expectations rose — and it was just a matter of us believing in the room that we could win every single night,” he said.
“Anaheim, the expectations were already high, they’d been to the conference finals the year before. They thought I was a guy who might help push them over the top, but the expectation was to win the Stanley Cup — that’s what the team was put together for, and we managed to accomplish that. It wasn’t really me going in there and changing anything, it was just adding a guy . . .”
Last summer, when GM Paul Holmgren pulled the trigger on a deal for Pronger that sent Joffrey Lupul, young defence prospect Luca Sbisa, two first-round picks and a third-rounder to Anaheim, there was no guarantee it would work the way it has.
Pronger’s overbearing personality clashed with captain Mike Richards’s Bobby Clarke-like presence, and there was a lot of pulling in different directions before order was restored, but the Flyers looked good coming into the season, and they look good now.
“Expectations were high, we didn’t necessarily live up to those off the hop,” Pronger said. “But it was just a matter of us finding our identity as a team.”
In the end, the identity settled on pugnacious, committed, sneaky-dirty, dangerous . . . and just a little arrogant. Where do you suppose that last bit came from?
© Copyright (c) canada.com


text:
Comments by Councilmember Mary Cheh:
Thank you, Mr. Chairman.
Largely my comments are focused on Ward 3, but they apply generally. This process has set the stage for inclusive and equitable growth across the District. Historically Ward 3 has lagged other parts of the district in contributing to those objectives. The Rock Creek West planning area, which contains Ward 3 has just 1% of the city’s affordable housing stock.
As we pursue the Mayor’s affordable housing goals and combat displacement, we have to embrace higher density residential development in places where that makes sense, which I think this Comp Plan largely achieves.
And the Comp Plan update so far has been a truly collective effort with meetings, town halls, public engagement. You know, out of my own office, extensive exchanges with groups and individuals and so on, and I’m pleased to see that the changes that have been suggested to the Chairman have largely been incorporated in this draft.
Proposed changes to the Future Land Use Map designating new and higher density mixed use areas properly located along the corridors, Wisconsin and Connecticut, will position Ward 3 communities to accommodate the need for growth. These changes reflect the notion that rezoning can encourage building, mostly residential, and help us cultivate a higher capacity and financially accessible Ward.
The integration of new residents isn’t just good for those residents. It’s also good for our existing communities. Older neighborhoods in marketplaces are at turning points. Our city and neighborhood serving retail centers simply need more neighbors to serve it they are going to continue to thrive.
Literally and figuratively, we will add new life and greater diversity and ultimately a more enlivened and robust community with the changes that are coming to the comp plan.
I’ve also balanced the priority for affordable denser development with the realities of our neighborhood context and I’ve worked with the Chairman to draw back some density designations such as in Cleveland Park, doing so to recognize that neighborhoods serving commercial areas and neighborhoods serving areas in general and historic districts obviously can’t bear the same scale of building as in, for example, some downtown areas.
Nevertheless, we can contribute meaningfully to affordable development.
And growth also isn’t something that developers should be able to impose at will by designating as future planning analysis areas. Many of the Ward 3 neighborhoods set to get higher density land use designations we can commit the District thoughtful planning and anticipation.
And I’ve asked the Rock Creek Element include language including smaller area plans in particular come before, that they precede rezoning in the ward such that all advocates may collectively inform growth.
Just briefly, I just note, however, that I am concerned about the Chairman’s reincorporation of inflexible presumptive language in the comp plan amendments, but we can discuss that further at some point.
Thank you again, Mr. Chairman for bringing the comp plan to mark-up and I look forward to hearing my colleagues’ perspective on the proposal.

domain: geography


Babies Can’t Wait (BCW) is a statewide early intervention program for families with children (under 36 months of age) with specific established or suspected developmental delays. BCW assists families in identifying needed resources and services within our community to meet a child’s developmental needs. Agencies and individuals provide services from both the public and private sectors that may include service coordination, speech, occupational, physical therapy and special instruction. Some services are at no cost to the family, while other services may require a cost participation from the family.
BCW is established by Part C of the Individuals with Disabilities Education Act (IDEA) which guarantees all eligible children, regardless of their disability, access to services that will enhance their development. Additional information about IDEA and national efforts supporting the implementation of the early childhood provisions of the law is available through the National Early Childhood Technical Assistance Center.
BCW utilizes an evaluation team to conduct selected screening tools and specific developmental evaluations to determine program eligibility. Once eligible, a coaching model is used guided by an Individualized Family Service Plan. The evaluation team writes the IFSP with information and input from the primary care physician, family, any relevant therapists and the SC. This includes goals that would include any family goals, developmental goals, personal health care services and the provision of health care that supports the identified developmental needs of the child. Therapists coach caregivers on how to implement strategies during normal routines and activities in the child’s natural environment.
For more information, contact the Cobb and Douglas Babies Can’t Wait Coordinator at (770) 319-4717.
For developmental screening and enrollment call (770) 514-2759.


Atomic force microscope for high speed imaging including integral actuator and sensor
A cantilever for a scanning probe microscope (SPM) includes a piezoelectric element in a thicker, less flexible section near the fixed base of the cantilever and a piezoresistor in a thinner, more flexible section near the free end of the cantilever. When the SPM operates in the constant force mode, the piezoelectric element is used to control the tip-sample separation. Since the resonant frequency of the piezoelectric element is substantially higher than that of conventional piezoelectric tube scanners, much higher scan rates can be achieved. When the SPM operates in the dynamic or intermittent contact mode, a superimposed AD-DC signal is applied to the piezoelectric element, and the latter is used to vibrate the cantilever as well as to control the tip-sample spacing. In another embodiment the cantilever is supported on a knife edge and vibrates at a third or higher order resonant frequency.
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FIELD OF THE INVENTION
This invention relates to scanning probe microscopes and in particular to a cantilever used in scanning probe microscopes.
BACKGROUND OF THE INVENTION
Scanning probe microscopes operate by scanning a probe over a surface that is to be examined, typically in a raster pattern. One type of scanning probe microscope is an atomic force microscope, in which the probe consists of a cantilever with a sharp tip located near its free end. As the cantilever is scanned, the tip interacts with the surface. This in turn causes physical changes in the cantilever which are detected and used to generate a representation of the surface, often down to an atomic scale. Other types of scanning probe microscopes include magnetic force microscopes and electric force microscopes, which detect phenomena other than the topography of a sample.
An atomic force microscope can operate in several modes. In the "contact" or "constant force" mode, the tip is maintained in contact with the surface. As the tip encounters topographical features of the surface, the cantilever is deflected or bent. These deflections are detected, and by means of a feedback system the distance between the cantilever and the surface is controlled so as to maintain a constant force between the tip and the surface. In the feedback system, a signal representative of the deflection of the cantilever is compared against a reference voltage to produce an error signal. Using the feedback electronics to hold the error signal to zero, an output is generated which both holds the error signal to zero by changing the tip-sample spacing, and generates a representation of the surface.
In the "dynamic" or "non-contact" mode the tip is brought very close to the surface, and the cantilever is vibrated at a frequency which is close to its resonant frequency. As the cantilever is scanned, the distance between the tip and the features of the surface varies. This in turn causes the gradient of the Van der Waals and other forces between the tip and the surface to change. Resulting changes in the vibrational amplitude, frequency or phase of the cantilever are detected, and again the distance between the cantilever and the surface is controlled by a feedback system to maintain the tip-sample separation at a constant.
The "cyclical" or "intermittent" contact" mode, described in U.S. Pat. Nos. 5,266,801 and 5,308,974, is somewhat similar to the dynamic mode, but the tip is allowed to strike the surface as the cantilever vibrates.
The separation between the cantilever and the sample surface is normally controlled by means of a piezoelectric tube on which the sample platform is mounted. The piezoelectric tube is part of the feedback system mentioned above. The output of the cantilever deflection detector is delivered to an input of the piezoelectric tube via the feedback electronics. Variations in this signal cause the tube to expand or contract along its axis and thereby adjust the position of the sample in relation to the cantilever in a direction normal to the surface of the sample. Alternatively, the cantilever can be mounted on the piezoelectric tube.
The ability of an atomic force microscope to generate images rapidly depends on the speed at which the cantilever is scanned over the sample. Typical scan speeds are in the range of 10 to 100 .mu.m/sec, which means that images take several minutes to generate. At speeds greater than this level, the cantilever, as it interacts with features on the sample surface, begins to interact at frequencies that approach the resonant frequency of the piezoelectric tube (typically between 2 and 10 kHz). When the piezoelectric tube moves into resonance, the feedback system used to maintain a constant tip-sample force (or spacing, if the microscope is operating in the dynamic mode) does not function properly.
By using the principles of this invention, the scan speed attainable by the cantilever can be significantly increased.
SUMMARY OF THE INVENTION
The cantilever of this invention is for use in a scanning probe microscope. The scanning probe microscope also includes a scanner for scanning the sample and a feedback system for controlling the separation between the tip and the sample.
The cantilever of this invention comprises two sections: an actuator section, which includes an actuator and is located relatively near the fixed base of the cantilever; and a bending section, which is associated with a deflection detector and is located relatively near the free end (tip) of the cantilever. The actuator controls the position of the tip relative to the sample. The deflection detector detects the deflection of the cantilever.
In most embodiments, the actuator section is relatively stiff and thick as compared to the bending section. As a result, the actuator section does not bend appreciably under the influence of a force on the tip. This creates an efficient coupling of any deflection of the cantilever into the bending section. Moreover, the relatively stiff actuator section can bend or move the bending section with little difficulty.
In the preferred embodiment, the actuator comprises a piezoelectric element, and the deflection detector comprises a piezoresistor which is integral to the bending section. In other embodiments, the actuator section may include, for example, a capacitive plate, and the deflection detector may include, for example, an optical detector, an interferometric detector or a capacitive detector.
When the microscope operates in the dynamic or intermittent contact modes, the actuator is used to vibrate the cantilever as well as to control the tip-sample separation. In the preferred embodiment, this is accomplished by applying an oscillatory signal to one of the electrodes of the actuator while applying a DC signal that is controlled by the output of the deflection detector to the other electrode.
In the preferred embodiment, the cantilever is formed of silicon, and the piezoelectric element comprises an electrode/ZnO/electrode sandwich which is attached to the silicon cantilever. A portion of the silicon adjacent the piezoelectric element is heavily doped with impurities and forms a conductive region which is part of the circuit which includes the piezoresistor. In accordance with another aspect of the invention, circuitry is provided for adjusting for stress that is induced in the heavily-doped silicon as a result of the expansion and contraction of the piezoelectric element. Circuitry is also provided for adjusting for currents that are induced in the conductive region by the current flowing through the piezoelectric element. These corrections are provided by properly calibrated amplifiers whose respective outputs are added into the feedback system.
Yet another aspect of this invention yields an additional technique for correcting for the electrical coupling between the piezoelectric element and the piezoresistor. An AC signal having a frequency substantially above the imaging bandwidth is applied to the piezoresistor, and the output of the piezoresistor is delivered to a lock-in amplifier, which effectively demodulates the AC signal and provides an output representative of the deflection of the cantilever. Any spurious signals which are created by the electrical coupling between the piezoelectric element and the piezoresistor will be at frequencies which are well below the AC signal and will therefore be ignored by the lock-in amplifier. Alternatively, a conductive shield layer may be used to prevent signals applied to the piezoelectric element from being coupled to the piezoresistor.
Because the resonant frequency of the piezoelectric element is significantly greater than the resonant frequency of a typical piezoelectric tube, the scan speed of the cantilever may be significantly increased.
In accordance with another aspect of the invention, a cantilever is supported on a knife edge structure and is vibrated at a higher mode of resonance. The actuator used to vibrate the cantilever could be piezoelectric or capacitive, for example. This arrangement facilitates faster scanning rates.
BRIEF DESCRIPTION OF THE DRAWING
The principles of this invention will be better understood by reference to the following figures of the drawing, in which like reference numerals are used to designate similar elements.
FIG. 1A illustrates a perspective view of a cantilever representative of a first embodiment in accordance with the invention.
FIG. 1B illustrates a perspective view of a cantilever representative of a second embodiment in accordance with the invention.
FIG. 2 illustrates a schematic block diagram of a cantilever and associated feedback system of an atomic force microscope designed to operate in the constant force mode.
FIG. 3A illustrates a block diagram of the Wheatstone bridge in the feedback system of FIG. 2.
FIG. 3B illustrates a block diagram of the feedback box in the feedback system of FIG. 2.
FIG. 3C illustrates a block diagram of the current-to-voltage meter in the feedback system of FIG. 2.
FIG. 3D illustrates a block diagram of an alternative current-to-voltage meter that can be used in the feedback system.
FIG. 3E illustrates a block diagram of the amplifier used to correct for induced piezoresistive stress and coupling current in the feedback system of FIG. 2.
FIG. 4 illustrates an arrangement including a lock-in amplifier which can be used to correct for capacitive coupling between piezoelectric element and piezoresistor.
FIG. 5 illustrates a circuit diagram of the balance circuit in the arrangement shown in FIG. 4.
FIG. 6 illustrates a graph which shows the variation of the voltage across the piezoresistor as a function of the frequency of the signal used to drive piezoelectric element.
FIGS. 7A and 7B illustrate embodiments of a cantilever in which a shield layer is used to prevent electrical coupling between the piezoelectric element and the piezoresistor.
FIGS. 8A and 8B illustrate the amplitude and phase response, respectively, of a cantilever having an integral piezoelectric element and piezoresistor.
FIG. 9A illustrates a schematic block diagram of a cantilever and associated feedback system of an atomic force microscope designed to operate in the dynamic or intermittent contact modes.
FIG. 9B illustrates a schematic block diagram of a dual feedback system that could be used in place of the feedback system shown in FIG. 9A.
FIG. 10 illustrates a graph showing the vibrational amplitude of the cantilever as a function of tip-sample distance when the cantilever is operating in the intermittent contact mode.
FIG. 11 illustrates a graph showing the shifting of the resonant frequency of the cantilever as the tip-sample distance varies.
FIG. 12A illustrates an embodiment of a cantilever including a piezoelectric element to be used at non-fundamental vibrational frequencies.
FIGS. 12B and 12C illustrate perspective and cross-sectional views, respectively, of a cantilever including a capacitive actuator to be used at non-fundamental vibrational frequencies.
FIGS. 13A and 13B illustrate the fundamental and third resonant modes, respectively, of a vibrating cantilever.
FIG. 14 illustrates a capacitive actuator in an alternative embodiment of the invention.
FIG. 15A illustrates an optical deflection detector in an alternative embodiment of the invention.
FIG. 15B illustrates an interferometric deflection detector in an alternative embodiment of the invention.
FIG. 15C illustrates a capacitive deflection detector in an alternative embodiment of the invention.
DESCRIPTION OF THE INVENTION
A cantilever according to one aspect of this invention includes two sections: an actuator section located relatively near the base of the cantilever and a bending section located relatively near the tip of the cantilever. FIG. 1A shows a cantilever 10 which includes a relatively thick actuator section 11 and a relatively thin bending section 12. Actuator section 11 is defined by a piezoelectric element 13, which comprises a zinc oxide layer 14 sandwiched between metal electrodes 15A and 15B. Alternatively, lead zirconate titinate (PZT) could be used instead of zinc oxide. As is apparent from FIG. 1A, in this embodiment cantilever 10 is U-shaped, and piezoelectric element 13 is therefore split into two parts which are attached to the legs of the cantilever, respectively. In other embodiments, the cantilever is solid and the piezoresistor and associated circuit elements are formed by patterned implantations.
Cantilever 10 is preferably formed on a silicon substrate 16 and includes a tip 17. In bending section 12, a layer of the silicon is lightly-doped (e.g., at 10.sup.18 cm.sup.-3) to form a piezoresistive element 18. The silicon underlying piezoelectric element 13 is more heavily doped (e.g., at 10.sup.20 cm.sup.-3) to form a conductive region 19 which adjoins piezoresistive element 18. The circuit which includes piezoresistive element 18 and conductive regions 19 is fed by a pair of bias lines 19A.
As indicated in FIG. 1A, actuator section 11 has a thickness T while bending section 12 has a thickness t. (FIG. 1A is not drawn to scale.) For example, T could be in the range 7-20 .mu.m and t could be in the range 1-5 .mu.m. Because T is considerably larger than t, actuator section 11 is substantially stiffer than bending section 12. In particular, assuming a given force against tip 17, the deflection of cantilever 10 is the double integral of the bending moment divided by the moment of inertia and Young's modulus. The bending moment is a function of the force against tip 17, and Young's modulus is a characteristic of the material, both of which are fixed. The moment of inertia is a parameter defined by geometry and has the form:
.intg..intg.y.sup.2 dy dx
where x and y are the distances from the center of the structure in horizontal and vertical directions, respectively.
For the rectangular geometry of cantilever 10, the moment of inertia is proportional to the thickness cubed. Therefore, assuming a constant Young's modulus for the entire structure, a force applied against tip 17 produces little bending in actuator section 11 because actuator section 11 is stiffer than bending section 12 by a factor of T.sup.3 /t.sup.3.
A voltage V.sub.pe is applied to the electrodes 15A and 15B of piezoelectric element 13. As is well-known, the zinc oxide intermediate layer expands and contracts as V.sub.pe is varied, causing actuator section 11 to bend. Since the base of cantilever is fixed, the bending of actuator section 11 causes the position of the tip 17 to change in a vertical direction.
With this configuration, the bending of actuator section 11 is effectively decoupled from the bending of section 12. That is, a perpendicular force against tip 17 will cause significant bending in section 12 but will have relatively little effect in actuator section 11. Conversely, the bending of actuator section 11 that is caused by the operation of piezoelectric element 13 is able to move or bend section 12 with little difficulty.
FIG. 1B illustrates a modified cantilever 20 in which the thickness t of section 22 is reduced to further increase the decoupling between sections 21 and 22.
A method of fabricating a cantilever similar to cantilevers 10 and 20 is described in the parent application Ser. No. 08/296,340, now abandoned which is incorporated herein by reference in its entirely.
As is well-known, cantilever 10 is scanned over a sample surface as tip 17 detects the topological features of the surface. Typically, the tip of the cantilever faces downwards and the cantilever is thus inverted from the position shown in FIG. 1A.
FIG. 2 illustrates, in block form, the feedback system that is used to control cantilever 10 when it is operating in the constant force mode. A sample 30 is mounted in a normal fashion on a piezoelectric tube scanner 31. Tube scanner 31 moves sample 30 in a horizontal pattern, typically so as to cause tip 17 to trace a raster pattern on the surface of the sample. Piezoresistive element 18 is connected as part of a Wheatstone bridge 32 (see FIG. 3A). The output of Wheatstone bridge 32 is fed to a summing unit 33, where it is added to the respective outputs of an induced stress correction unit 34 and a coupling current correction unit 35, one embodiment of which is shown in FIG. 3E. The summed outputs are then delivered to a feedback box 36 (See FIG. 3B). The output of feedback box 36 is used to generate an image of sample 30 and is also sent as V.sub.pe to piezoelectric element 13. The output of feedback box 36 is also delivered to induced stress correction unit 34, and via a current-to-voltage meter 37 to coupling current correction unit 35.
As shown in FIG. 3A, piezoresistive element 18 is connected in Wheatstone bridge 32 along with resistors R.sub.1 and R.sub.2 and a variable resistor R.sub.3, which is used for adjustment purposes. Normally, the resistance of variable resistor R.sub.3 is set to equal the resistance of piezoresistor 18 when the latter is in an unflexed condition. The resistors R.sub.1 -R.sub.3 and piezoresistor 18 are connected in parallel conduction paths between a Vbias and ground. The common points between resistors R.sub.1 and R.sub.2 and between variable resistor R.sub.3 and piezoresistive element 18 are delivered to the inputs of an amplifier A.sub.1. As section 12 of cantilever 10 bends, the resistance of piezoresistive element 18 varies, and amplifier A.sub.1 delivers an output which is representative of the bending of section 12.
Feedback box 36, which is illustrated in FIG. 3B, contains a summing unit 42, a gain unit 43 and an integrator 44. The inputs of summing unit 42 are the signal from Wheatstone bridge 32 and a setpoint which is used to set the desired force between the tip of the cantilever and the sample surface. In a conventional manner, the output of summing unit 42 is amplified in gain unit 43 and integrated in integrator 43.
In other embodiments of this invention, feedback box 36 could employ, instead of an integral feedback, proportional feedback or differential feedback, or a combination thereof.
Accordingly, when cantilever 10 is operating in the contact mode, the bending of section 12 is detected in Wheatstone bridge 32 and sent via feedback box 36 to piezoelectric element 13. Piezoelectric element 13 causes actuator section 11 to bend so as to restore the desired force between tip 17 and the surface of sample 30. As distinguished from many prior art systems, the output of feedback box 36 is not sent to piezoelectric tube scanner 31 to restore the desired force between tip 17 and sample 30.
As shown in FIG. 3C, current-to-voltage meter 37 includes an amplifier A.sub.2 and a resistor R.sub.4, the latter being connected in the series path between feedback box 36 and piezoelectric element 13 and across the input terminals of amplifier A.sub.2. The output of amplifier A.sub.2 is thus a voltage which represents the size of the current flowing into piezoelectric element 13.
Units 34 and 35 are used to adjust for errors which may occur in the system. Considering first induced stress correction unit 34, conductive region 19 (FIG. 1A) is heavily doped so as to be as conductive as possible, but in some circumstances it may retain some piezoresistive properties. In these cases, the bending of actuator section 11 by piezoelectric element 13 may create a piezoresistive effect which is read by Wheatstone bridge 32 as resulting from a bending in section 12. As shown in FIG. 3E, induced stress correction unit 34 contains an amplifier A.sub.3 having a specified gain. In many instances the piezoresistive effect induced in region 19 is a linear function of V.sub.pe. Amplifier A.sub.3 is calibrated by varying V.sub.pe while the tip 17 is suspended in mid-air. When the change in resistance of region 19 as a function of .DELTA.V.sub.pe has been determined, amplifier A.sub.3 is adjusted so as to compensate for this effect, i.e., the value of the parameter "a" in the transfer function out =ax is determined (see FIG. 2). This is accomplished by setting the gain of the amplifier itself as well as adjusting the resistance provided by potentiometer R.sub.5. If the relationship between .DELTA.V.sub.pe and the voltage drop across bias lines 19A is nonlinear (e.g., out=ax+bx.sup.2), a more complex amplifier may have to be used for unit 34.
Since piezoelectric element 13 acts as a capacitor, at higher frequencies a substantial current may flow through it, and this current may in turn induce a current in conductive region 19 which will produce a spurious output on bias lines 19A. This can occur either when cantilever 10 is used in the dynamic or intermittent contact mode, where V.sub.pe is an oscillating signal which causes the cantilever to vibrate at a frequency near resonance, or when cantilever 10 is used in the constant force mode, where high frequencies may be generated by feedback box 36.
As described above, the output signal from current-to-voltage meter 37 represents the current flowing into piezoelectric element 13. Coupling current correction unit 35 compensates for the effect of the current induced in conductive region 19 as a result of the current into piezoelectric element 13. Unit 35 is calibrated by applying a range of frequencies to piezoelectric element 13 and measuring the shifts in the output voltage on lines 19A as the frequency is varied. Typically, there is no effect until the frequency reaches a certain level, and after that point is reached the output voltage varies linearly with frequency. Again, a linear amplifier will often suffice, but a second or higher order amplifier may be required if the relationship between the frequency of V.sub.pe and the spurious output on lines 19A is not linear.
When the cantilever is operating, the respective outputs of units 34 and 35 are added to the output of Wheatstone bridge 32 so that the signal V.sub.pe delivered to piezoelectric element 13 has been adjusted to compensate for the induced stress and coupling current effects. If units 34 and 35 are omitted from the arrangement shown in FIG. 2, the output of Wheatstone bridge 32 is directed to the input of feedback box 36, and current-to-voltage meter 37 is omitted.
FIGS. 4 and 5 illustrate an alternative arrangement which can be used to correct for the capacitive coupling between piezoelectric element 13 and piezoresistor 18. FIG. 6 illustrates a graph which shows the variation of the voltage across piezoresistor 18 as a function of the frequency of the signal used to drive piezoelectric element 13. The data in FIG. 6 were derived experimentally by applying an AC drive signal to piezoelectric element 13 with the tip of the cantilever suspended in midair and measuring the voltage across piezoresistor 18. The vertical axis of FIG. 6 is in units of mV per V.sub.ZnO, where V.sub.ZnO is the amplitude of the AC signal applied to piezoelectric element 13. Since the tip is not in contact with a surface, the piezoresistor is unstressed (except at the resonant frequency evidenced by the spike at about 28 kHz). If there were no capacitive coupling, the curve in FIG. 6 would be a horizontal line at 0 mV/V.sub.ZnO.
In the arrangement shown in FIG. 4, the elements which are the same as those shown in FIG. 2 are designated by similar numbers. In place of Wheatstone bridge 32, however, a balancing circuit 120 is connected to piezoresistor 18, and an output of balancing circuit 120 is delivered to a lock-in amplifier 121. Balancing circuit 120 and lock-in amplifier 121 are driven by an oscillator 122, which in this embodiment operates at 130 kHz.
FIG. 5 illustrates a circuit diagram of balance circuit 120. An output of oscillator 122 is directed to a transformer T.sub.1 which has a grounded center-tapped secondary coil and produces equal and opposite sinusoidal signals at nodes A and A' (shown as V sin .omega.t and -V sin .omega.t). Piezoresistor 18 is connected into a bridge 123, which includes a resistor R.sub.10 having a resistance equal to piezoresistor 18. Resistors R.sub.11 and R.sub.12 are also balanced (in this embodiment at 3.3K). Resistor R.sub.11 is in series with the parallel combination of a variable resistor R.sub.13 and a variable capacitor C.sub.1. Resistor R.sub.12 is in series with a variable resistor R.sub.14. Bridge 123 is balanced such that the voltages at nodes B and B' are both equal to zero when the cantilever is undeflected by adjusting resistors R.sub.13 and R.sub.14 and by adjusting capacitor C.sub.1 to match the parasitic capacitance in the circuit. Nodes B and B' are connected to the inputs of a differential amplifier A.sub.10, which in this embodiment has a gain of 500. The output of differential amplifier A.sub.10, whose amplitude represents the deflection of cantilever 10, feeds an input of lock-in amplifier 121. Lock-in amplifier 121 demodulates the output of balance circuit 120 and delivers the demodulated signal to feedback unit 36. As shown in FIG. 4, the output of feedback unit 36 flows to the upper electrode of piezoelectric element 13.
Using the arrangement shown in FIGS. 4 and 5, any spurious signals in piezoresistor 18 which are created by capacitive coupling between piezoelectric element 13 and piezoresistor 18 will be at frequencies which are well below 130 kHz and will therefore be ignored by lock-in amplifier 121.
FIGS. 7A and 7B illustrate other arrangements that can be used to minimize any capacitive coupling between piezoelectric element 13 and piezoresistor 18. In FIG. 7A, a conductive shield layer 140, preferably of metal, has been interposed between piezoelectric element 13 and piezoresistor 18. Shield layer 140 covers the top surface of cantilever 10 and is separated from piezoelectric element 13 by an insulating layer 141, which could be formed of an oxide or nitride. Shield layer 140 is grounded. FIG. 7B illustrates a modified version in which a bottom electrode 15C of piezoelectric element 13 extends over the top surface of cantilever 10. Since electrode 15C is grounded, it acts as a shield to prevent the input signal to piezoelectric element 13 from being electrically coupled to piezoresistor 18.
FIGS. 8A and 8B illustrate the amplitude and phase response of a cantilever having an integral piezoelectric element and piezoresistor. The cantilever had a length of 620 .mu.m and a ZnO piezoelectric element at its base which accounted for 265 .mu.m of the total length. The piezoelectric element had a thickness equal to that of the cantilever beam (3.5 .mu.m) and was able to deflect the cantilever up to 4 .mu.m. The cantilever was placed with its tip in contact with a fixed surface, and the piezoelectric element was driven at various sinusoidal frequencies. The amplitude and phase shift of the cantilever were recorded with an additional lock-in amplifier, which in this test was used in conjunction with a voltage divider arrangement rather than the preferred bridge circuit shown in FIG. 5.
Assuming an allowable phase margin of 45.degree., FIGS. 8A and 8B indicate that the cantilever had a maximum imaging frequency (bandwidth) of about 6.4 kHz. The resonance of the cantilever with its tip in contact with the sample surface was near 44 kHz. The gradual roll-off of the phase below the resonance frequency of the cantilever indicates that the imaging bandwidth was limited by the detection electronics rather the mechanical response of the cantilever. An imaging bandwidth equal to the resonant frequency should be attainable if the piezoresistor and lock-in amplifier are driven at a frequency much higher than resonance.
Also shown in FIGS. 8A and 8B are the amplitude and phase characteristics of a piezoelectric tube actuator having a length of 2 inches (a commonly used size for scans of up to 100 .mu.m). The sharp phase shift near 550 Hz is associated with the significantly lower resonance of the piezoelectric tube.
Using an arrangement similar to that shown in FIGS. 4 and 5, an image of an integrated circuit was taken with a tip velocity of 1.6 mm/sec. The sample, which contained vertical steps 1.5 .mu.m in height, was raster scanned over a 15 .mu.m.times.15 .mu.m area using a one-inch long piezoelectric tube with a fast scan rate of 50 Hz. A high resolution image of 512.times.512 pixels was obtained in about 15 seconds. By adding an interlace to the slow scan (which was ramped with a triangular wave) and changing the pixel array to 128.times.128, it was possible to obtain images at a rate of several frames per second.
A feedback system which is particularly suitable when cantilever 10 is operating in the dynamic or intermittent contact modes is illustrated in FIG. 9A. Electrode 15B of piezoelectric element 13 is connected to the output of an oscillator 40, which in this example supplies a voltage signal with a frequency in the range of 200 KHz to 2 MHz and an amplitude ranging from 10 mV to 20 V. With cantilever 10 vibrating, the output of Wheatstone bridge 32 is an oscillating signal which is passed to an RMS-to-DC converter 41. To reduce mechanical coupling from the induced zinc oxide actuation, the output of Wheatstone bridge 32 is first passed through a high-pass filter 32A. This added filter attenuates frequencies in the imaging bandwidth while passing frequencies near the cantilever driving frequency. RMS-to-DC converter 41 acts as an amplitude detector which delivers a DC output which is representative of the root mean square of the amplitude of the signal delivered by Wheatstone bridge 32. Other devices, such as homodyne detectors, synchronous demodulators and lock-in amplifiers, could be used in place of RMS-to-DC converter 41 as an amplifier detector.
The output of RMS-to-DC converter 41 is summed with the setpoint voltage in summing unit 42 and is passed through gain unit 43 and integrator 44 to a high voltage amplifier 45. The output of amplifier 45 is delivered to electrode 15A of piezoelectric element 13. As tip 17 encounters features of sample 30, the force gradient between the tip and sample varies, causing the vibrational amplitude of cantilever 10 to change. This change is reflected in the output of Wheatstone bridge 32 and consequently in the DC voltage delivered by RMS-to-DC converter 41. After being summed and amplified, this altered DC signal is delivered to electrode 15A of piezoelectric element 13, causing the cantilever to bend by an amount necessary to restore the required separation between tip 17 and sample 30.
An important feature of this arrangement is that piezoelectric element 13 is used to cause cantilever 10 to vibrate and at the same time to control the tip-sample separation. This is accomplished by superimposing or summing the respective outputs of amplifier 45 and oscillator 40. (While piezoelectric element actually sees the difference between these signals, the effect is the same as summing because the output of oscillator 40 is typically a sinusoidal signal. Subtracting a sinusoidal signal from a DC signal is equivalent to adding the DC to the sinusoidal signal phase-shifted by 180 degrees.)
Alternatively, one of the electrodes of piezoelectric element 13 could be grounded and the outputs of oscillator 40 and amplifier 45 could be delivered to an external summing amplifier, with the output of summing amplifier being passed to the other electrode of the piezoelectric element. The arrangement shown in FIG. 9A, however, avoids the need for the external summing amplifier.
In other embodiments, piezoelectric tube 31 is used in combination with piezoelectric element 13 to control the tip-sample separation of cantilever 10. The dual feedback system for such an embodiment is shown in FIG. 9B. The output of RMS-to-DC converter 41 is also connected to an integral feedback box 46 which is similar to feedback box 36, and the output of feedback box 46 is connected to the z-movement input of piezoelectric tube 31. A feedback box 47, which uses a combination of integral and proportional feedback, is substituted for feedback box 36. Feedback box 47 includes an additional gain unit 48 connected in parallel with gain unit 43 and integrator 44.
In the embodiment of FIG. 9B, the z-movement of piezoelectric tube 31 (which also controls the x,y movement of the sample) is used in combination which z-movement of piezoelectric element 13 to provide a constant tip-sample separation. In the preferred embodiment, piezoelectric tube 31 handles the low-frequency feedback, arising for example from the tilt of the sample and large topographical features in the sample, and piezoelectric element 13 handles the high frequency feedback which is necessary to increase the overall bandwidth of the system. The advantage of having piezoelectric tube 31 and piezoelectric element 13 share the control of the tip-sample separation is that the system is more tolerant of sample height changes (whether from sample tilt or other factors) that fall outside the range of the piezoelectric element 13. The overall quality of the feedback may also be improved.
FIGS. 10 and 11 illustrate changes in the behavior of cantilever 10 when it is operating in the dynamic or intermittent contact modes. In FIG. 10, the horizontal axis is the separation between the base of the cantilever and the sample in nanometers, with zero representing the separation that exists when the tip 17 and sample are in contact and tip 17 is not vibrating (negative separations thus represent conditions in which the cantilever is flexed). The vertical axis is the amplitude of vibration of cantilever 10 expressed in a normalized scale from 0 to 1. When the separation is less than about -40 nm, there is essentially no vibration. In the "intermittent contact" region, the vibrational amplitude increases quite linearly with increasing separation. Beyond the "intermittent contact" region, the sample does not interfere with the vibration of the cantilever, and the amplitude reaches a plateau.
FIG. 11 illustrates the vibrational amplitude of cantilever 10 at two tip-sample separations as the frequency of the output of oscillator 40 (FIG. 9A) is varied. Curve X.sub.1 shows the amplitude when the tip is relatively close to the surface, and curve X.sub.2 shows the amplitude when the tip is relatively far from the surface. Assuming an output of oscillator 40 at a frequency W.sub.drive, it is seen that the amplitude increases from Y.sub.1 to Y.sub.2 as the tip is moved away from the surface of the sample. Referring to FIG. 9A, the difference between amplitude Y.sub.1 and amplitude Y.sub.2 is reflected in the output of Wheatstone bridge 32 and consequently the DC output of RMS-to-DC converter 41.
Correction units similar to induced stress correction unit 34 and coupling current correction unit 35 may also be used when the cantilever is operating in a dynamic or intermittent contact mode. FIG. 12A, however, illustrates an embodiment which may avoid the need for such corrections. It has been disclosed that cantilevers have several resonant modes of oscillation (see Luginbuhl et al., "Piezoelectric Cantilever Beams Actuated by PCT Sole-Jel Thin Film", Transducers '95 Eurosensors IX, pages 413-416). FIGS. 13A and 13B illustrate the fundamental and third resonant modes, respectively, in both of which the free end of the cantilever experiences a maximum amplitude of vibration. (The same is true in other higher order resonant modes in which the free end of the cantilever vibrates.) From FIG. 13B, it is apparent that there is a zero point approximately one-third of the distance from the tip of the cantilever.
In the embodiment of FIG. 12A, a cantilever 70 is supported by a knife edge 71 at the location of this zero point. Cantilever 70 is vibrated by a piezoelectric element 72, which is similar to piezoelectric element 13 shown in FIG. 1A. A piezoresistor 73 is formed in cantilever 70 in a manner similar to that used in forming piezoresistor 18 in cantilever 10 (FIG. 1A). Bias lines 74A and 74B connect to piezoresistor 73. Because there is no conductive region (similar to conductive region 19 shown in FIG. 1A) adjacent the piezoelectric element 72 the induced stress and current coupling problems discussed above are not incurred. In some embodiments a single piezoelectric element may be used to vibrate a group of cantilevers.
FIGS. 12B and 12C show perspective and cross-sectional views, respectively, of an embodiment which uses a capacitive or electrostatic actuator to control the cantilever. Cantilever 80 is supported by a knife edge 81. Knife edge 81 is positioned a distance L1 from the free end of the cantilever and a distance L2 from the base of the cantilever. A platform 82 beneath the cantilever extends from the base to the free end of the cantilever and beyond. Two conductive regions 83 and 84 are formed under the knife edge on opposite sides of the knife edge 81. If the platform 82 is formed of silicon, for example, conductive regions 83 and 84 may be heavily-doped implantations.
A piezoresistor 85 is formed in cantilever 80 in the region between the knife edge 81 and the tip of the cantilever. Piezoresistor 85 is supplied with a current through bias lines 86A and 86B, and conductive regions 83 and 84 are connected to voltage sources through lines that are not shown in FIGS. 12B and 12C.
An electric field E1 applied to conductive region 84 will pull the tip of the cantilever downward, and an electric field E2 applied to conductive region 83 will pull the tip of the cantilever upward. Thus, with this embodiment two independent mechanisms of control for cantilever 80 are provided. For example, as shown in FIG. 12C, an alternating signal could be applied to conductive region 83 at a frequency which corresponds to the second resonant mode of cantilever 80, with knife edge 81 being located at the zero point (see FIG. 13B). Simultaneously, a DC signal could be applied to conductive region 84 in order to control the sample-tip separation. In such an arrangement, piezoresistor 85 would detect the bending of cantilever in Region 1 and would be connected through a Wheatstone bridge to a feedback system which would provide a control signal for conductive region 84.
In another embodiment, an alternating signal could be applied to conductive region 84 and a DC signal could be applied to conductive region 83, or the cantilever could be operated in the contact mode with DC signals applied to conductive regions 83 and 84. Other variations will be apparent to those skilled in the art.
The speed at which images can be generated has been a limitation of scanning probe microscopy. For cantilevers operating in the contact mode, this is attributable primarily to the need to keep the frequency of the signal generated by the cantilever below the resonant frequency of the cantilever and the piezoelectric element that is used to control the tip-sample separation. The resonant frequency of a conventional piezoelectric tube is in the range of from 2 to 10 kHz. For a cantilever operating in the contact mode, a bandwidth in the range of 1 kHz generally permits a scanning frequency of 2 to 20 Hz, depending on the size of the scan. The typical scan rate is in the range 10 to 100 .mu.m/sec.
A piezoelectric element such as element 13 shown in FIG. 1A has a significantly higher resonant frequency than that of a typical piezoelectric tube scanner. Piezoelectric tubes can have resonances down to 500 Hz depending on the size of the tube and the mass of the sample mounted on the tube, whereas a cantilever can have fundamental resonant frequencies as high as 1 MHz. This allows scan rates on the order of 1 mm/second, which is two orders of magnitude higher than the prior art norm. Operating in the intermittent contact mode, and vibrating the cantilever in a higher resonant mode at a frequency of 250 kHz, scan rates of more than 2 mm/second have been achieved. For scan sizes of a few microns, this allows the screen to be updated at a rate of more than once each second, and gives an atomic force microscope a "feel" similar to that of a scanning electron microscope. Since the tip only lightly taps the sample surface, it is not believed that tip wear will be a problem. Using the principles of this invention, high speed imaging can be used to map large areas of topography (up to 100.times.100 .mu.m.sup.2) while, if necessary, lower scanning speeds can be used where high resolution is necessary.
Using a cantilever with an integral actuator may also significantly reduce the time required to bring the tip of the cantilever safely to a position on or near the sample surface at the commencement of the analysis. This engage process entails lowering the cantilever towards the surface with a stepper motor until the cantilever sensor (piezoresistor, optical, etc.) receives information that the tip is near the surface and then signals the motor to stop or change speeds. The cantilever sensor may also signal a piezoelectric tube (on which the sample or cantilever is mounted) to quickly retract, thereby creating a short, controlled distance between the tip and the sample.
Because the response time of a typical piezoelectric tube is quite low, the approach must be made very slowly to insure that the tip is not damaged in a collision with the sample surface. Using an integral actuator to control the separation between the tip and the sample would reduce the response time from approximately 1 ms to 1 .mu.s. This allows the stepper motor to lower the tip to the surface at a much more rapid rate, thereby significantly reducing the approach time. At present, the approach times for commercial scanning probe microscopes are on the order of a minute; using an integral actuator can reduce this time to less than a second.
While the preferred embodiment includes a piezoelectric element as the actuator and a piezoresistor as the deflection detector, other embodiments contain alternative devices for the actuator and deflection detector. Several of these alternative embodiments are described below.
A capacitive plate of the kind described in parent application Ser. No. 08/296,340 can be used in place of the piezoelectric element as the actuator. FIG. 14 illustrates a capacitive plate 90 which is formed adjacent a cantilever 91. Capacitive plate 90 is formed in the actuator section 11 and terminates before the beginning of the bending section 12. An electric signal is applied between capacitive plate 90 and cantilever 91 to cause the actuator section 12 to bend or vibrate in the manner described above.
FIGS. 15A, 15B and 15C illustrate several alternative deflection detectors which can be used in embodiments of the invention. FIG. 15A shows an optical detector in which a laser beam 100 is reflected off the back of cantilever 101. As cantilever 101 deflects, the reflected laser beam strikes a position sensitive photodetector 102 at different locations, allowing the deflection of cantilever 100 to be measured. The displacement of beam 100 at photodetector 102 is equal to the deflection of the cantilever 101 multiplied by the ratio between the distance of the detector from the cantilever and the length of the cantilever. A piezoelectric element 103 is shown in actuator section 11. The optical detection method is described in G. Meyer et al., Appl.Phys.Lett. 53, 1045 (1988), which is incorporated herein by reference in its entirety.
FIG. 15B shows an interferometric detector 104 which includes an optical fiber. An optical cavity is formed between the end of the fiber and the back of cantilever 101. The interference between light reflected off the back of the cantilever and light reflected at the end of the fiber is used to measure the position of the cantilever. The interferometric detection method is described in R. Erlandsson et al., J.Vac.Sci.Technol., A 6, 266 (1988), which is incorporated herein by reference in its entirety.
FIG. 15C shows a deflection detector in which a capacitive plate 105 is placed parallel to the cantilever. A voltage is impressed between the cantilever and the capacitive plate, and variations in the capacitance are measured as the cantilever deflects. The capacitive detection method is described in T. Goddenhenrich et al., J.Vac.Sci.Technol., A 8, 383 (1990). A process of fabricating a capacitive plate adjacent to a cantilever is described in J. Brugger et al., MME '92, Third European Workshop on Micromachining, Micromechanics and Microsystems. Each of the foregoing articles is incorporated herein by reference in its entirety.
With the deflection detectors illustrated in FIGS. 15A-15C, a feedback system similar to the one shown in FIG. 2 would be employed, but Wheatstone bridge 32 would be omitted, the output of the deflection detector being applied to feedback box 36. Without a piezoresistive deflection detector, correction units 34 and 35 would not be needed.
While several embodiments according to this invention have been described, it will be understood that numerous alternative embodiments will be apparent to those skilled in the art. For example, the principles of this invention are applicable to any kind of scanning probe microscope, including but not limited to magnetic and electric field microscopes. The broad scope of this invention, as defined in the following claims, is intended to cover all such embodiments.
1. A scanning probe microscope comprising:
- a cantilever comprising an integral piezoelectric actuator and a piezoresistor; and
- a feedback system linking said piezoresistor and said piezoelectric actuator, said feedback system comprising a balance circuit connected to said piezoresistor and a lock-in amplifier connected to an output of said balance circuit, said balance circuit and said lock-in amplifier being connected to an output of an oscillator, an output of said lock-in amplifier representing a deflection of said cantilever and being used to drive said piezoelectric actuator.
2. The scanning probe microscope of claim 1 wherein said balance circuit comprises a transformer and a bridge circuit, said piezoresistor being connected in said bridge circuit.
3. The scanning probe microscope of claim 2 wherein said balance circuit further includes a differential amplifier, an output of said bridge circuit being connected to an input of said differential amplifier.
4. The scanning probe microscope of claim 1 wherein said feedback system further comprises a feedback box, said feedback box being connected between an output of said lock-in amplifier and said piezoelectric element.
5. The scanning probe microscope of claim 4 wherein an output of said feedback box is connected to a first electrode of said piezoelectric element, a second electrode of said piezoelectric element being connected to ground.
6. A method of analyzing the surface of a sample, said method comprising:
- providing a scanning probe microscope, said scanning probe microscope including a cantilever and a feedback system for controlling the distance between said cantilever and said surface;
- bringing a tip of said cantilever into a position adjacent said surface;
- scanning said surface with said tip at a rate in excess of 1 mm/second.
7. The method of claim 6 wherein said step of scanning comprises maintaining a constant force between said tip and said surface.
8. The method of claim 6 wherein said step of scanning comprises operating said scanning probe microscope in the intermittent contact mode.
9. The method of claim 6 wherein said step of scanning comprises scanning said surface with said tip at a rate in excess of 2 mm/second.
10. A method of bringing a cantilever of a scanning probe microscope into position to analyze a sample surface, said method comprising:
- incorporating an integral piezoelectric actuator and an integral piezoresistor in the cantilever;
- causing said cantilever to approach said sample surface;
- detecting when a tip of said scanning probe microscope is near said sample surface; and
- actuating said piezoelectric actuator so as to retract said tip a selected distance from said surface.
11. The method of claim 10 wherein the step of causing a cantilever to approach said sample surface is performed using a stepper motor.
12. The method of claim 10 wherein said step of detecting when said tip is near said sample surface is performed using said integral piezoresistor.
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Wang et al., "Nanometer-Structure Writing On SI(100) Surfaces Using a Non-Contract-Mode Atomic Force Microscope", Appl. Phys. Lett., vol. 65, No. 11, 12 Sep. 1994, pp. 1415-1417. Wolf et al., "Silicon Processing For The VLSI Era Vol. 1: Process Technology", Lattice Press, 1986, pp. 209-210. "Thermomechanical writing with an atomic force microscope tip", H.J. Mamin et al., Appl. Phys. Lett. 61(8), 24 Aug. 1992, pp. 1003-1005. "The atomic force microscope used as a powerful tool for machining surfaces", T.A. Jung et al., Elsevier Science Publishers, 1992, pp. 1446-1451. "25 nm chromium oxide lines by scanning tunneling lithography in air", H.J, Song et al., 38th Int'l Symp. on Electron, Ion and Photon Beams, New Orleans, LA, May 31-Jun. 3, 1994, pp. 16 pgs. "Nanometer-scale lithography using the atomic force microscope", A. Majumdar et al., Appl. Phys. Lett. 61(19), 9 Nov. 1992, pp. 2293-2295. "Tip-induced anodization of titanium surfaes by scanning tunneling microscopy: A humidity effect on nanolithography", H. Sugimuar et al., Appl. Phys. Lett. 62(9), 30 Aug. 1993, pp. 1288-1290. "Nanometer scale patterning of silicon (100) surfaces by an atomic force microscope operating in air", L. Tsau et al., Appl. Phys. Lett. 64(16), 18 Apr. 1994, pp. 2133-2135. "Fabrication of Si nanstructures with an atomic force microscope", E.S. Snow et al., Appl. Phys. Lett. 64(15), 11 Apr. 1994, pp. 1932-1934. "Lithographic patterning of self-assembled films", J.M. Calvert, J. Vac. Sci. Technol. B 11(6), Nov./Dec. 1993, pp. 2155-2163. "Self-assembled monolayer electron beam resist on GaAs", R.C. Tiberio et al., Appl. Phys. Lett. 62(5), 1 Feb. 1993, pp. 476-478. "Low voltage electron beam lighography in self-assembled ultrathin films with the scanning tunneling microscope", C.R.K. Marrian et al, Appl. Phys. Lett. 64(3), 17 Jan. 1994, pp. 390-392. "Scanning Probe Lithography. 1. Scanning Tunneling Microscope Induced Lithography of Self-Assembled n-Alkanethiol Monolayer Resists", C.B. Ross et al., American Chemical Society, Langmuir, vol. 9, No. 3, 1993, pp. 632-636. "Modification of Silicon Surface Produced by Electric Field Enhanced Oxidation Through Native Oxide", Y. Ejiri et al., Extended Abstracts of 1993 Int'l Conf. on Solid State Devices and Materials, 1993, pp. 606-608. "Fabrication of silicon nanostructures with a scanning tunneling microscope", E.S. Snow et al., Appl. Phys. Lett. 63(6), 9 Aug. 1993, pp. 749-751. "Nanometre-scale chemical modification using a scanning tunnelling microscope", Y. Utsugi, Nippon Telegraph and Telephone Corp., LSI Laboratories, undated, 2 pgs. "Atomic Force Microscopy Using A Piezoresistive Cantilever", M. Tortonese et al., IEEE, Mar. 1991, pp. 448-450. "Fabrication of Si nanostructures with an atomic force microscope", E.S. Snow et al., Appl. Phys. Lett. 64(15), 11 Apr. 1994, 12 pgs. "Applications of Atomic Force Microscopy for Nanolighography", P.I. Oden et al., undated, 7 pgs. Technology of proximal probe ligthography, "Principles and Techniques of STM Lithography", M.A. McCord et al, 1993, The Society of Photo-Optical Instrumentation Engineers, pp. 16-32. Technology of proximal probe lithography, "Low Voltage E-Beam Lithography with The STM", C.R.K. Marrian et al, 1993, The Society of Photo-Optical Instrumentation Engineers, pp. 58-73. Technology of proximal probe lithography, "The Technology of Proximal Probe Lithography: An Overview", J.A. Dagata et al, 1993, The Society of Photo-Optical Instrumentation Engineers, pp. 3-11. "Nanometer Lithography on Silicon and Hydrogenated Amouphous Silicon with Low Energy Electrons", Kramer et al., abstract, International Conference on Micro and Nanofabrication, Sep. 1994. N. Kramer et al., "Fabrication of Metallic Nanowires with a Scanning Tunneling Microscope", 1995 American Institute of Physics, Appl. Phys. Lett. 66 (11), 13 Mar. 1995, 1325-1327. "Silicon transfer layer for multilayer resist systems", J.B. Kruger et al., J. Vac. Sci. Technol., 19(4), Nov./Dec. 1991, pp. 1320-1324.
Filed: Oct 31, 1995
Date of Patent: Mar 16, 1999
Assignee: The Board of Trustees of the Leland Stanford, Jr. University (Stanford, CA)
Inventors: Stephen Charles Minne (Danville, IL), Calvin F. Quate (Stanford, CA), Scott Manalis (Stanford, CA)
Primary Examiner: Safet Metjahic
Assistant Examiner: Daniel P. Malley
Attorney: Skjerven, Morrill, MacPherson, Franklin & Friel
Application Number: 8/558,563
International Classification: G01B 528;


Google just showed off some AR glasses that will translate the world for you
Okay, that is pretty cool.
Who remembers Google Glass? That was Google's ill-fated attempt at bringing AR glasses to the world. They came out when the tech was still in its infancy and people were put off because of privacy concerns.
Now, though, with AR tech embedded in our phones - if you haven't used Google Lens, try it now! - it may well be the right time to bring out some new wearables for the face.
At its Google IO conference, Google showed a sneak peak of some prototype glasses, in a video that showcased them translating someone in real time, offering up subtitles of what they are saying through the glasses.
If they work like the video shows, then this could be something that could revolutionise the way we talk to people around the world. That's a big if, mind.
We were impressed with what we saw, though. Head to the Twitter video below to see what you think.
Augmented reality can break down communication barriers – and help us better understand each other by making language visible. Watch what happens when we bring technologies like transcription and translation to your line of sight. #GoogleIO ↓ pic.twitter.com/ZLhd4BWPGh
— Google (@Google) May 11, 2022
Speaking about its push into AR, Google's big boss Sundar Pichai noted: "Looking ahead, there is a new frontier of computing, which has the potential to extend all of this even further. And that's augmented reality. At Google, we've been heavily invested in this area. We have been building augmented reality into many Google products from Google."
He continued: “Language is so fundamental to connecting with one another. Yet, understanding someone who speaks a different language or trying to follow a conversation if you’re deaf or hard of hearing can be a real challenge.
“Let’s see what happens when we take our advancements in translation and transcription and deliver them in your line of sight in one of our early prototypes.”
Will we ever see the glasses come to the market? No idea. Google has been burnt before in this area, but the video is pretty awesome.
And if you want to know about the Google gadgets that are real and being released this year and next, then head to our report on the show.


text:
In a sense, it's a little disappointing that the "Land of the Free" took so long to get around to something like marriage equality, but I'm not going to let that get in the way of enjoying something that's been a long, long time coming. In the end, the Supreme Court just ratified what America as a whole has already determined. That's not to say it wasn't a long, difficult, and bitter fight, but in the end, the court didn't lead so much as just recognize reality.
I was raised in a very different time. That being the case, I'm going to have to have to re-learn some nomenclature and un-learn some assumptions. That's fine by me. Societies changes and language changes to accommodate those changes and older folks like myself have to adapt. These are symptoms of growth and progress. I'm going to get my words wrong sometimes, I'll mistakenly assume that when a guy gets married that he'll have a "wife," and I'll be embarrassed. I won't do it on purpose, and I'll expect to be corrected when I get it wrong. I'll get there, just bear with me.
On the other hand, I don't expect ever to understand how people can feel bitter and belittled by other people getting the same freedoms that they already enjoy. It strikes me as petty and selfish to think that your rights are less valuable when they're extended to more people. At that point, you're not talking about "rights," you're talking about "privilege." Perhaps someone can explain it to me in terms that make sense to me, but to date, no one has managed it.
In a roundabout way, today is going to be kind of a watershed for speculative and science fiction writing. From this point forward, any story about a future that doesn't include same-sex relationships is going to look dated and naive. It's going to feel implausible. This is a good thing. We as a people have grown a little bit and our stories should reflect this.
This isn't the end of the road by any stretch of the imagination. There are plenty of institutional biases still entrenched in society and in law that need to be swept away. There are certianly many, many more that I'm not even aware of, and there will new ones emerging every generation. There is no final destination on the path to reform. Reform is a process. That doesn't mean it's not worth doing, and it certainly doesn't mean we shouldn't celebrate with abandon when we get it right.
So, congratulations to the Supreme Court of the United States and everyone living in America: You got this one right. I feel much more excited about getting married now that it's a more inclusive institution. I'll close with this: I think today should be a national holiday. Either the 26th of June or the last Friday in June. How does "Freedom Day" sound to you?


text:
Beleduc - Speed Star - Small
Accelerate with your feet! Due to its special construction the Speed Star offers a totally new driving experience. Through precise left and right movements of the feet the vehicle can be navigated accurately. The comfortable and ergonomically formed seat in combination with the innovative handles ensure your safety.

domain: design


text:
By Nick Worth
Paring its senior unsecured debt from $153 million down to $25 million last December was a major accomplishment for Prospect Global Resources Inc. (PGR), but now the company has announced a further reduction in the amount it owes to The Karlsson Group, having just inked a deal to lower the amount owed down to $15 million in cash.
Prospect Global is one of the two major potash-mining concerns in the Holbrook basin. The company has owed millions of dollars to The Karlsson Group since agreeing to buy Karlsson’s interest in American West Potash.
On Dec. 17, PGR made a deal with Karlsson to lower the cash owed in the deal from approximately $148 million to $25 million. According to a filing with the Securities Exchange Commission (SEC) in December, Prospect Global had until March 10 of this year to raise the $25 million payoff to Karlsson.
Once March 10 arrived and PGR could not make the $25 million payment to Karlsson, the company was able to negotiate an extension agreement with Karlsson on March 13, moving the date for the $25 million payment from March 13 to April 10, according to a PGR SEC filing.
In this latest deal, PGR has succeeded in lowering the cash payment amount it owes to Karlsson from $25 million to $15 million and has extended the due date by another 13 days, to April 23.
According to a press release from Prospect Global, PGR has filed a registration statement with the SEC for a public offering intended in part to fund this payment.
The Karlsson Group will keep all of its existing rights related to the debt until it is paid off.
The press release states the PGR currently has “approximately $153.1 million of obligations outstanding to its senior secured lender (Karlsson) with a maturity in July 2015. This amount will be extinguished with the $15 million payment.”
Prospect Global will also increase Karlsson’s royalty interest from 2 percent to 3 percent, and issue additional shares of common stock and warrants to purchase common stock as part of the deal.
In related news, PGR has been delisted from the NASDAQ stock Exchange as of Monday.
“On April 3, 2014, we received written notification from The NASDAQ Stock Market that our common stock will be suspended from trading on The NASDAQ Stock Market effective at the open of business on Monday, April 7, 2014,” reads an SEC filing and news release from PGR. The statement notes that the reason for the delisting is that PGR has not achieved compliance with a NASDAQ listing rule that requires a minimum market value of listed common stock of $35 million.
“We have been advised that our common stock will be eligible for trading and quotation on the OTCQB market, under the symbol ‘PGRX,’ effective at the open of the market on Monday, April 7,” reads the SEC filing. “…the OTCQB market is operated by OTC Markets Group Inc., which operates the world’s largest electronic marketplace for broker-dealers to trade unlisted stocks. Investors can find current financial disclosure and quotes for the company at www.otcmarkets.com.”
In the SEC filing, PGR states, “Prospect Global intends to pursue listing on a national exchange upon successful completion of the previously announced extinguishment of its senior secured debt to The Karlsson Group, Inc.”
At the announcement of the move to OTC, PGR stock prices fell to a one-year low of $1.05 per share.
An online check of PGR’s stock prices on Tuesday showed the company listed in the OTC.
By Nick Worth

domain: economics


text:
We were sat in the office and looking at our bills and to be honest I knew very little about LPG other than the fact that a friend has had an LPG Land Rover for over 2 years. But when you discover that the price of LPG is 50p a litre and we were paying £1.31 per litre for diesel...95 per cent of our fuel bill is diesel for the vans, and it's a lot of money.
UK (PRWEB) October 18, 2008
A vehicle-leasing company has launched a new business to maximise the growing demand for liquefied petroleum gas, LPG vans and cars after arranging a deal which saved a client an estimated £500,000 on its fleet of vans.
Square 1 Leasing, based in Lymm, Cheshire, was set up in February by the £22m-turnover IT distribution firm Square1 Products Ltd alongside vehicle and finance provider Andrew Poole. It has now launched LPG Fleet Solutions to target medium-size companies which currently use diesel vehicles.
Poole said the move into LPG was prompted after it supplied four vehicles for Lancashire-based electrical engineering firm Hirst & Danson.
Joe Makepeace, Hirst & Danson's health and safety manager, said the monthly fuel bill for its 26 vans had doubled to £14,000. Makepeace said: "We were sat in the office and looking at our bills and to be honest I knew very little about LPG other than the fact that a friend has had an LPG Land Rover for over 2 years. But when you discover that the price of LPG is 50p a litre and we were paying £1.31 per litre for diesel...95 per cent of our fuel bill is diesel for the vans, and it's a lot of money."
Hirst & Danson, which turns over £13m a year, expects to receive around £70,000 from the sale of its old vans, which is being handled by LPG Fleet Solutions. The upfront costs of leasing the new fleet will mean there is a net cost to the business in years one and two but, by the end of the three-year lease, it predicts to be in profit by £250,000 when compared to the cost of continuing to operate a diesel fleet.
However, the firms have agreed a deal that will let Hirst & Danson keep the vans under a full-service and maintenance agreement for a further two years, leading to a total £450,000 saving over a five-year period.
"The fact that I can gain a new fleet and save myself money seems almost insane when you think about it," said Makepeace.
Poole said the difference between the cost of a new diesel van and a converted LPG was "negligible". The cost of converting a new petrol van to LPG is typically between £1,700-£2,000, making the total cost roughly similar to that of a diesel model.
Conversion to an LPG fleet will also help firms to reduce their carbon footprint by up to 30 per cent. Poole said that this is useful when tendering for public sector work, as quasi-governmental clients such as the Olympic Delivery Authority expect contractors to say how they minimise environmental impact when they tender.
"I'd love to say we were looking at it because we were concerned about our environmental footprint, but really it was all about the numbers," said Makepeace. "When you looked at them it was a no-brainer."
A spokesman for Transport for London said that drivers of "certain alternative fuel vehicles" do not have to pay its congestion charge so long as the vehicle is registered with them, but said potential purchasers could check eligibility against the PowerShift Register -- a register of vehicles approved by the Energy Saving Trust.

domain: news


text: I am a huge fan of books. Not just reading them, but having them around. I love how a wall of books looks in our house. I love meandering through libraries and book stores. And, I really love the smell of an old book You might also be interested in: No related posts.

domain: library


text:
Actress Malini Kapoor, who became a mother in December last year, is excited about her first holiday with son Kiyan in Jaipur.
“It’s like holidaying after so many years. It’s a special one because it’s Kiyan’s first travel.
“Ajay (husband) is also a concerned father. I’m lucky to have two boys — Ajay and Kiyan — in my life. We are enjoying Jaipur,” Malini said in a statement.
She has featured in shows like “Y.A.R.O Ka Tashan” and “Rang Rasiya”.


text: Sorry, ET lovers: That "fossilized thigh bone" spotted on Mars this week was really just (can you bear the tension) a rock, NASA says. "No bones about it!" writes the agency on its website. "Mission science team members think its shape is likely sculpted by erosion, either wind or water." The Houston Chronicle calls NASA scientists "space agency killjoys" for explaining that any life in Mars' history likely existed at the microbial level, owing to a lack of oxygen to support complex life forms. And CNET notes that the rock was too crooked to be a thigh bone anyway. But today's alien enthusiasts aren't the first to dream: Astronomers claimed to see canals on Mars in the 1800s, and fans interpreted a "face" amid the light-and-shadow play of a 1976 photo of the planet's surface, Space.com reports.


text:
This picture perfectly sums up our day because we started in Seattle under the shadow of Mt. Rainer and ended up in Tokyo where we were found a coffee with a picture of Mt. Rainer.
A big shout out to our beloved friend Jenn for driving us down to Seattle to meet up with more beloved friends, Lia, Bjorn & Frank. We had a great dinner party last night and breakfast this morning in Fremont.
Then off to the airport to start the next leg of our travel adventure – this time we’re heading to Asia – Japan, Thailand, Laos, Cambodia, Vietnam and Hongkong until mid November.
Away we go!
After a quick ride on the Narita Express, we arrived in Shinjuku.
So tired, but we managed the strength to order delicious ramen from this machine.


text:
The care of the sick at home and in the hospital : a handbook for families and for nurses
- Billroth, Theodor, 1829-1894.
Where to find it
Location of original
This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.
Francis A. Countway Library of Medicine
About this work
London : Sampson Low, Marston & Co., 1891.
337 pages, 14 leaves of plates ; 19 cm
Translation of: Die Krankenpflege im Hause und im Hospitale

domain: medical


text:
SYRACUSE, Ind. (WANE) – A statewide Silver Alert has been declared for Aaliyah Ramirez.
The Syracuse Police Department is investigating the disappearance of Aaliyah Ramirez, a 14-year-old white female, 5 feet 9 inches tall, 138 pounds, black hair with brown eyes, last seen wearing a black zip-up jacket, gray and white sweatpants, and a purple Nike backpack.
Aaliyah is missing from Syracuse, Indiana, which is 147 miles north of Indianapolis, and was last seen on Tuesday, April 27, 2021, at 8:01 am. She is believed to be in danger.
If you have any information on Aaliyah Ramirez, contact the Syracuse Police Department at 574-267-5667 or 911.


text:
The Cimbria Centricoater is designed for the application of coating value added seeds with costly seed treating materials. The system is a continuous batch operation utilising a highly accurate inlet scale together with a highly accurate chemical dosing system controlled by a PLC.
The system provides improved seed coverage and a more uniform distribution of treatment materials on the seed as compared to traditional continuous operating drum type treaters.
Main attention is also paid to economical use of the expensive coating- slurries, thus simply saving money for our valued customers. Therefore, Centricoaters have a very short pay off period.
The heart of the Centricoater is the mixing chamber, consisting of a stainless cylindrical housing with rotating bottom (rotor). The seed is gently dropped from the continuous batch electronic scale into the chamber onto the rotor. This rotor moves the seed gently up to the stationary chamber side wall causing a folding of seed from outward to inward in the chamber. A spinning disk in the centre of the mixing chamber, on which the treating materials are delivered from the PLC controlled dosing system, atomises the liquid treating materials into the vertical seed layer. This provides a highly intensive uniform application of seed treatment material on each kernel of seed. All kinds of treating material, liquids and powders, can be applied effectively in this system.
The Cimbria Centricoater innovation is a fine example of our advanced equipment. As the Centricoater reduces the consumption of chemical agents, the impact on the environment is subsequently reduction in raw material use. The results are homogenous seed which all have fine growth ability and meet the international standards for certified seeds.
Permanent process monitoring and data- logging by the Centricoaters PLC- control greatly support our customers in their internal quality control as well as inventory management.
CC Lab (2 kg); CC10 Lab (10 kg);
CC10 (1,8 t/h); CC20 (4,5 t/h);
CC50 (9 t/h); CC150 (18 t/h);
CC250 (25 t/h); CC250 DUO (50 t/h);

domain: agronomy


text:
Page 1 of 21
Polemic I: The Origin
Wandering throughout the lands beyond our world, our Lord Etahn found a beautiful land. He watched this place from afar, observing its people go about their lives. Toiling the land, waiting long hours hoping their crops may
Page 2 of 21
grow in order to see another day.
Etahn pitied their way of life. Putting in such great effort for a reward they may never see, due to the threat of conflict and war these people faced constantly. How could they tolerate living this way?
Page 3 of 21
Despite this, He admired these people for their will to create and their perseverance even when faced with the most trying of circumstances. Etahn wished to help them.
Page 4 of 21
Polemic II: The Gift
One day, Etahn began to see great swathes of land disappear. He found these people He admired gathering, awaiting the end of their world. Despite the end of this world coming, Etahn knew a fresh world would take its place, and that
Page 5 of 21
these people would return with it.
And so the world ended, and as Etahn knew, a new one took its place. These people once again began to return to their previous lives. Building cities anew, toiling their land and facing the hardships they had
Page 6 of 21
Etahn saw a man sitting beside a pool atop a hill. He went to him and talked to this man. The man taught Him of their world and pleaded Etahn to help.
Etahn told the man He would imbue his essence into what
Page 7 of 21
these people knew as Clay. He said this Holy material would bless the land with life and fertility, helping the land and its people prosper. He said all those in this land would recieve His Gift, but those that followed His teachings and worshipped Him
Page 8 of 21
would be blessed, and those that deserved His wroth would be cursed.
Our Lord dipped His hand into the pool. Pillars of Clay rose to the sky as the pool poured out His Holy waters, to flow their way throughout the world to spread His
Page 9 of 21
blessing. And with that, the world was forever changed.
Page 10 of 21
Polemic III: The Claymandments
I: Accept me as your God, giver of this gift that has blessed your land. Worship me above all else.
II: Do not desecrate that which is Holy.
Page 11 of 21
III: Words are wind, those that truly wish to prove their devotion to me must commit themselves to the Clayjj Pilgrimage. Journey to this place where I have given My gift unto your lands. Meditate by its pools, wash yourself clean with its Holy waters,
Page 12 of 21
and add a piece of blessed Clay to this Holy site.
Page 13 of 21
V: I know that war will always exist in this land. I know your victories will be great and many, so I ask that you do not destroy the wonders of this world created by its people and your enemies- no matter how small.
Page 14 of 21
VI: I ask that you do not permanently punish or imprison those who oppose you or wrong you. They are simply led astray by their inner demons and deserve a chance to see the way of the Clay. To give themselves unto me and have their souls moulded anew- if
Page 15 of 21
they prove themselves worthy of it.
Page 16 of 21
VII: Your kind may always have those that lead and those that follow, for better or for worse. As long as this is so a leader shall care for his followers as he would care for himself, and a follower shall repay this care with their loyalty and respect.
Page 17 of 21
VIII: Conduct yourself with poise and light heartedness. I have seen what there is far beyond this world. You are not alone nor are you the most important beings in existance. This is not a cause for despair, but should act as a way to put yourself in
Page 18 of 21
perspective with the world. Treat others kindly because anything else is a waste of time and energy that could otherwise be put towards fun and love.
Page 19 of 21
IX: Your lands and its people have faced strife and will face more that will cause them to become wary and fearful of their fellow man, seeing a threat in each of them. You must never surrender to these fears. Never deny another the right to be your guest
Page 20 of 21
unless you know they will act dishonorably in return or must otherwise. Let them into your halls, eat your bread, warm by your fires and never bring them harm. It is a betrayal most grave for guest and host to harm eachother.
Page 21 of 21
X: Live your life free. I give you this gift not so you can exert your control over nature and amass its wealth, but so you may live a life free from the chains of hardship and labour. Free to live a life you yourself desire.

domain: literature