Abstract: A stiffener assembly which provides for improved performance of a movable stage arrangement. Often, it is desired to provide a movable stage arrangement in which a stage moves linearly with respect to a stationary base. In many applications, it is necessary for the stage to move to successive rest positions, with movement of the stage inhibited at each of the reset positions. The stiffener of the present invention allows for controlled movement of a stage along its direction of travel, with the stiffener inhibiting undesired movement when the stage is at a rest position. In one form, a stiffener extends in the direction of travel of the stage, with one end of the stiffener assembly mounted to the stationary base, and the other end urged into frictional contact with the movable stage by a force applicator. As a result, the stiffener is placed in frictional contact with the movable stage.

Abstract: An apparatus and method for scanning a probe over a surface to either produce a measurement of the surface representative of a parameter other than the topography of the surface or to perform a task on the surface. The scanning operation is divided into two parts and with a first scan to obtain and store topographical information and with a second scan to measure the parameter of the surface other than topography or to perform the task while the probe height is controlled using the stored topographic information.

Abstract: A two dimensional piezoelectric positioning device of the type including a thin walled cylindrical shaped member of piezoelectric material. A plurality of substantially rectangular shaped members are positioned around one surface of the cylindrical shaped member to form opposite pairs of electrodes to control the two dimensional movement in accordance with voltages applied to the pairs of electrodes. Each rectangular shaped member is split into at least two electrode portions and with particular polarity voltages applied to the individual electrode portions to maintain a substantially constant length for the cylindrical shaped member during the two dimensional movement.

Abstract: A microscope of the scanning probe variety. This device circumvents one of the serious problems of prior art scanning probe microscopes, i.e. that the probe is always near or on the surface of the object being scanned, creating the danger of damaging the probe on the surface especially on large scans or at high scan speeds. The microscope of this invention jumps the probe over the surface, causing the probe to be near or on the surface during only a very limited portion of the scan and therefore able to scan quickly over rough surfaces without undue damage to the probe or surface. Both scanning tunneling microscopes and atomic force microscopes employing the invention are disclosed. The scanning tunneling microscope is shown with both digital and analog control of the movement of the probe.

Abstract: This invention is a dual mode atomic force microscope which has significant advantages for small samples. The major point of novelty of this device is the provision for mounting samples onto the deflection mechanism, thereby allowing the tip to be separately mounted. The invention therefore allows for increased flexibility in the design of the tip, which can improve the performance of the microscope. The main configuration and several tip designs and variations of the deflection mechanism and the sample holder are described. Also, methods for using a microscope of this type are presented. The invention primarily consists of an AFM where the sample is mounted on the cantilever arm, and the tip is mounted separately, not on the cantilever arm. The cantilever arm and sample are scanned relative to the sample either by moving the sample or by moving the tip.

Abstract: This invention is an atomic force microscope having a digitally calculated feedback system which can perform force spectroscopy on a sample in order to map out the local stiffness of the sample in addition to providing the topography of the sample. It consists of a three-dimensional piezoelectric scanner, scanning either the sample or a force sensor. The force sensor is a contact type with a tip mounted on a cantilever and a sensor to detect the deflection of the lever at the tip. The signal from the sensor goes to an A-D convertor and is then processed by high-speed digital electronics to control the vertical motion of the sample or sensor. In operation, the digital electronics raise and lower the piezoelectric scanner during the scan to increase and decrease the force of the tip on the sample and to use the sensor signal to indicate the change in height of the tip to measure the which is the spring constant of the sample. This constant can be determined with nanometer spatial resolution.

Abstract: A microscope of the scanning probe variety. This device circumvents one of the serious problems of prior art scanning probe microscopes, i.e. that the probe is always near or on the surface of the object being scanned, creating the danger of damaging the probe on the surface especially on large scans or at high scan speeds. The microscope of this invention jumps the probe over the surface, causing the probe to be near or on the surface during only a very limited portion of the scan and therefore able to scan quickly over rough surfaces without undue damage to the probe or surface. Both scanning tunneling microscopes and atomic force microscopes employing the invention are disclosed. The scanning tunneling microscope is shown with both digital and analog control of the movement of the probe.

Abstract: This invention is an atomic force microscope having a digitally calculated feedback system which can perform force spectroscopy on a sample in order to map out the local stiffness of the sample in addition to providing the topography of the sample. It consists of a three-dimensional piezoelectric scanner, scanning either the sample or a force sensor. The force sensor is a contact type with a tip mounted on a cantilever and a sensor to detect the deflection of the lever at the tip. The signal from the sensor goes to an A-D convertor and is then processed by high-speed digital electronics to control the vertical motion of the sample or sensor. In operation, the digital electronics raise and lower the piezoelectric scanner during the scan to increase and decrease the force of the tip on the sample and to use the sensor signal to indicate the change in height of the tip to measure the which is the spring constant of the sample. This constant can be determined with nanometer spatial resolution.

Abstract: A method of adjusting the scan size of an instrument having piezoelectric scanners, such as a scanning probe microscope, including operating the instrument at a first scan size and adjusting the scan size of the instrument to a second scan size. The instrument is then precycled by scanning in each of x and y directions over substantially maximum excursions in each direction for a number of scan lines less than a complete scan of an area of the second scan size. The precycling settles the sensitivities of the piezoelectric scanners. The instrument is then operated at the second scan size to obtain data indicative of the surface of a scanned object.

Abstract: A method for locating a chemical substance on the surface of a material and for determining the contour of a surface of a material using a scanning electrochemical microscope is provided in the present invention. The substance to be examined is immersed in a solution, the tip of a working electrode is positioned in the solution proximate the surface and an electric potential is connected directly or indirectly between the tip and the material generating a current through the tip and producing an electrochemical reaction. The current through the tip is measured at a plurality of points while the tip is scanned across the surface. The current at each point in the scan is preferably plotted to produce an image of the contour or of the differing chemical compositions on the surface of the substance being examined. The solution in which the substance and working electrode tip are immersed is chosen to enable electrochemically generated reduction and oxidation processes to occur between the surface and the tip.

Abstract: This invention relates to Scanning Probe Microscopes (SPMs) and the like that use piezoelectric type scanners. The scanner described herein limits non-linear errors in the vertical scan direction while maintaining a large horizontal scan size. A tube scanner is shown wherein the tube comprises two portions. The first tube has first (x,y) electrodes attached thereto and is of a first piezoelectric material having high sensitivity qualities in response to voltages applied to the first electrodes. The second tube has second (z) elecrodes attached thereto and is of a second piezoelectric material having sensitivity qualities in response to voltages applied to the second electrodes which are lower than those of the first piezoelectric material. In one embodiment, the first tube and the second tube have substantially identical diameters and are attached to each other in end-to-end concentric relationship.

Abstract: This is an atomic force microscope in which the sensor can be built as a very small integrated structure. The sensor utilizes optical interference and can be operated in either the contact mode for high resolution or in the non-contact mode to measure electric and magnetic fields. One configuration of this microscope is a stand-alone configuration in which the microscope can be placed on or be suspended above large samples for scanning of small local areas thereof. The sensor is built into a scanner so that the sensor can be scanned over a stationary sample.

Abstract: This invention is a scanning probe microscope which uses three separate motorized legs to adjust the distance between the probe and sample and to adjust the tilt between the probe and the sample. The microscope is shown configured in various ways. One form is a scanner on a base in which the base contains the sample and legs. Another is a scanner which contains the legs and rests on the sample, or may also rest on a support that spans a larger sample allowing translation of the sample independent of the scanner. Another is a scanner which contains the legs and is mounted so that a sample holder sits on the legs. The latter configuration allows for easy access to the sample. One variation of this configuration has provision for the mounting of several samples which can be sequenced for probing automatically.

Abstract: The invention is a method for operating a Scanning Probe Microscope (SPM) to provide the capability to eliminate the scanner drift that occurs after the scan area is offset within the range of the scanner. The method disclosed comprises applying an offset that is larger than the desired one and then reducing the offset back to the desired value for scanning. The technique has been found to produce good results for both large and small scans.

Abstract: This invention is an enhanced probe positioning technique for Scanning Tunneling Microscopes, Atomic Force Microscopes, and other scanning probe microscopes. The invention has particular application for drift compensation. The invention adds a controllable motion to the probe that is totally independent of the scanning or other probe positioning. If the drift velocity is known, the invention can be used to compensate for the drift. In addition, several implementations are shown for measuring drift velocity. One method has the operator identify a significant feature of the acquired image on separate frames of data. The shift of this pattern or feature, along with the time between frames, can be used to calculate the drift velocity. Two methods are described that utilize the frequency shift of the image spatial spectrum due to the effect of the drift velocity on bi-directional scans. Another method is described that derives drift velocity and direction from the correlation of separate frames of data.

Abstract: A scanning tunneling microscope is corrected in real time for coupling effects from the scanning electrodes or bias voltage circuit of the microscope on the tunneling current. In an automatic embodiment, a test voltage waveform is applied to the scanning electrodes or bias voltage circuit, the system determines the correction required and corrects the tunneling current signal. A method enables the operator to verify the correction. In other embodiments, predetermined values of the parameters of the coupling effects are entered by the operator; the system determines the correction required from these values and corrects the tunneling current signal with this correction; the correction is verified, and the operator enters an adjustment of the values, if the corrections did not sufficiently correct for the coupling effects.

Abstract: In a scanning device producing an image from data obtained from a nonlinear piezoelectric scanner having an attached end and a free end providing the data from a lateral scanning motion of the free end a distance about a center position as a result of the connection of a changing scan voltage to elecrodes carried by the piezoelectric scanner, a method of making the scanning motion of the free end linear with time and increasing the speed at which the data is provided for producing the image.

Abstract: This is an atomic force microscope in which the sensor can be built as a very small integrated structure. The sensor utilizes optical interference and can be operated in either the contact mode for high resolution or in the non-contact mode to measure electric and magnetic fields. One configuration of this microscope is a stand-alone configuration in which the microscope can be placed on or be suspended above large samples for sanning of small local areas thereof. The sensor is built into a scanner so that the sensor can be scanned over a stationary sample.

Abstract: A scanning probe microscope head, which includes means for scanning a probe over a limited portion of a sample surface, includes a casing having feet resting on the sample surface and is moved by positioning means to different portions of the sample surface while the head slides across the sample surface. In one embodiment, a positioning arm is mounted on a carriage driven by a first feed screw, while a sample support is mounted for adjustment by a second feed screw perpendicular to the first. In a second embodiment, the arm is mounted on an X-Y stage adjusted by perpendicular feed screws. In another embodiment, the head rests on the support surface for the sample and slides along this surface as its position is adjusted. The positioning arm supports one or two magnets which magnetically couple the arm to the head casing. The casing is made of ferromagnetic material or nonmagnetic material with a ferromagnetic insert.

Abstract: A feedback control system for enhancing the feedback loop characteristics of a vertical axis control in a scanning tunneling microscope or the like, including a tip member for positioning relative to a surface for measuring the topography of the surface. A horizontal control coupled to the tip for providing a plurality of adjacent horizontal scans across the surface. A vertical control coupled to the tip for providing a vertical control of the tip during the plurality of adjacent horizontal scans. A local error signal produced in accordance with the vertical position of the tip relative to the surface in real time during the plurality of adjacent horizontal scans.