34 results about "Atomic force acoustic microscopy" patented technology

A method for determining properties of a sample surface using an atomic force microscope includes applying a first voltage between the sample and a probe, moving the probe towards the surface of the sample, and stopping movement of the probe towards the surface of the sample when current in the probe is initially detected. An oscillating magnetic field is applied to the probe such that the probe obtains stable contact with the surface of the sample.

There is disclosed a scanning probe microscope for producing a topographic image of a surface of a sample by noncontact AFM (atomic force microscopy). First, a first topographic image of the sample undergoing magnetic effects is produced from the resonance frequency of a cantilever by FM detection. Then, a second topographic image of the sample free of magnetic effects is produced from the amplitude of the cantilever by slope detection. The difference between these two topographic images is taken. Thus, a magnetic force image is produced.

A probe (22) for an atomic force microscope is adapted such that, as a sample (14) is scanned, it experiences a biasing force Fdirect urging the probe towards the sample. This improves probe trackingof the sample surface and faster scans are possible. This is achieved by either including a biasing element (24, 50), which is responsive to an externally applied force, on the probe (22) and / or reducing the quality factor of a supporting beam. The biasing element may, for example, be a magnet (24) or an electrically-conducting element (50). The quality factor may be reduced by coating the beamwith a mechanical-energy dissipating material.

The invention discloses a force tracing method for an atomic force microscope (AFM), which relates to the technical field of micro force measurement methods and solves the problem that force signals obtained by the traditional AFM single molecule force spectrum method are easily regarded as signals generated by motions of an AFM probe but not signals generated in a dynamic process on cell surfaces. The force tracing method for the AFM comprises the following steps of: after needle feed is finished under the control of a feedback regulation system, closing the feedback regulation system, and determining a position of the AFM probe in a Z direction when the AFM probe is contacted with the surface of a tested object through an obtained force-distance curve; gradually approaching the AFM probe to the surface of the tested object, and when the AFM probe is just contacted with the surface of the tested object, closing the feedback regulation system and stopping feeding the probe to ensure that a cantilever is deflected immediately; and acquiring a relation of the deflection of the cantilever along with time by utilizing a data acquisition card. According to the force tracing method, influences of the motions in the Z direction of the AFM probe driven by a piezoelectric ceramic scanner on dynamic process researches of the surface of the tested object are avoided.

The invention discloses an imaging system of an atomic force microscope (AFM) on the basis of a quartz tuning fork probe. An AFM controller in the system is respectively connected with a graphic display, a piezoelectric ceramic tube scanner, a drive circuit of a stepping motor, a feedback signal detection circuit and a scanning control signal processing circuit through wire cables so as to achieve transmission of electrical signals, a probe limiting seat is installed on a sample table, a round mounting table is mounted above the probe limiting seat, and the piezoelectric ceramic tube scanner, a displacement adjusting component and a circuit mounting box which is supported by four supporting columns are installed on the round mounting table. By means of the imaging system of the AFM on the basis of the quartz tuning fork probe, a student can know basic working principles of the AFM and operating steps of the imaging system, and the imaging system can be used for observing a microstructure of a sample. During an experiment, the student can measure force sensor--quartz tuning fork probe damping coefficient of the imaging system and observe bistable state phenomena to further understand AFM force action mechanism and parameter setting.

The invention relates to a single particle or single molecule tracking device and method based on an atomic force microscope. The tracking method comprises the following steps that before tracking measurement of a single particle or a single molecule is conducted, the point of a probe of the atomic force microscope is trimmed with a detection object; in the process of tracking measurement, the probe of the atomic force microscope makes contact with the surface of a detected object with constant force; when the detection object and the detected object act to each other, a micro cantilever deflects, and the telescopic distance of piezoelectric ceramics of a scanner is changed; a data acquisition card is used for collecting the changes over time of the deflection of the micro cantilever and the changes over time of the telescopic distance of the piezoelectric ceramics, so that the single particle or the single molecule is tracked. The single particle or single molecule tracking method based on the atomic force microscope can be applied to a study on the dynamic process of cell endocytosis viruses, nano particles and other particles, and is also suitable for a study on the transfer process of glucose, amino acid and other small biological molecules on cytomembrane.

An atomic force microscope includes a tip mounted on a micromachined cantilever. As the tip scans a surface to be investigated, interatomic forces between the tip and the surface induce displacement of the tip. A laser beam is transmitted to and reflected from the cantilever for measuring the cantilever orientation. In a preferred embodiment the laser beam has an elliptical shape. The reflected laser beam is detected with a position-sensitive detector, preferably a bicell. The output of the bicell is provided to a computer for processing of the data for providing a topographical image of the surface with atomic resolution.

The present invention relates to a method of tracking an atomic force acoustical microscopy probe contact resonant frequency. The method enables the single frequency square wave excitation to substitute for the sine wave frequency sweep based on a spectrum analysis method and by the fast Fourier transform (FFT), thereby avoiding the influence of a frequency sweep process to the imaging speed of the atomic force acoustical microscopy, and realizing the fast tracking of the atomic force acoustical microscopy probe contact resonant frequency.

Atomic force microscope measuring device comprising a micro-cantilever and an intensity modulated laser exciting the cantilever, wherein the measuring device comprises an optical microscope, in particular a fluorescence microscope, a confocal microscope, a fluorescence energy transfer (FRET) microscope, a DIC and/or phase contrast microscope, all of those in particular construed as an inverted microscope.

This invention discloses an atomic force microscope measurement method based on angle measurement, which belongs to the test system and device of the signals of atomic force microscope APM probe and cantilever. The said angle measurement device comprises calibration light source, focus lens, a quarter of wavelet, light splitter, two threshold prism, two photoelectricity diodes, Z-tracing micro-driver, two-dimensional micro-scanners in plane, probe clamper and APM probe. And the sample bench and the two-dimensional micro-scanner and APM probe and Z-tracing micro driver are separated with adjustable distance.

The invention discloses a method for precise orientation by an atomic force microscope. The precise orientation method comprises steps of: firstly finding a sample to be measured by an optical microscope; putting a copper net Center_Marked Grids above the sample to be measured, the copper net being formed by ruled grids with the same size, recording the region of the grids corresponding to the sample to be measured under the optical microscope, scanning the Center_Marked Grids by using an atomic force microscope, reducing the scanning area stage by stage, locating a probe of the atomic force microscope above the corresponding grids of the sample to be measured; and finally, softly blowing the Center_Marked Grids from side by using a washing ear ball; thereby carrying out the precise observation of the atomic force microscope by knitting stitch. The method can precisely orientate the sample to be scanned.

The invention discloses an atomic force microscope and a test method of a sample surface property. The atomic force microscope comprises a signal generator, a probe component, Z-direction piezoelectric ceramics, a laser generator, a photoelectric detector, a displacement coarse adjustment unit, a controller, and a sample stage. The probe component comprises a probe and an excitation module. The probe includes a cantilever beam and a needle tip located at a first end of the cantilever beam. The excitation module is connected to a signal generator, is used for receiving an excitation signal anddrives the probe to deflect at a first direction under the effect of the excitation signal. The excitation module is a non-laser photothermal excitation module. In the technical scheme of the invention, a vibration frequency of the probe is greatly increased so as to effectively speed up a speed when the surface property to be tested is tested by using a non-resonant tapping mode, and shorten testtime of the same surface to be tested.

The invention relates to a device for an atomic force microscope (AFM) for the study and/or modification of surface properties. The device comprises a cantilever (flexible bar) having an integrated, piezoresistive sensor, an integrated bimorphic actuator, and a measuring tip. The measuring tip carries at least two metal electrodes, which can be activated via electrical terminals. The measuring tip and/or the cantilever have at least one nanoscopic hole through which synchrotron radiation or laser light is directed onto the material surface to be studied. Furthermore, the invention relates to a method for the study and modification of surface properties and surface-proximal properties, which can be executed using such a device. To this end, atomic force microscopy (AFM), surface enhanced Raman scattering (SERS), photo emission spectroscopy (XPS, XAS), and material modification by local exposure are executed in sequence or simultaneously using the same device.

The invention relates to a method of precision measurement of nanometer clearance of a nanometer structure based on an atomic force microscope, the method comprising: scanning the central region of a top surface of a target sample, and positioning the tip of a probe at the center of the sample; loading/unloading a vertical force with the probe of the atomic force microscope until the bottom surface of the sample contacts the substrate; and recording a force curve of the atomic force microscope during loading/unloading, so as to obtain a nanometer clearance between the bottom surface of the sample and the substrate. Specifically, the method comprises: calibrating the sensitivity of a micro cantilever of the atomic force microscope; positioning the tip of the probe of the atomic force microscope at the geometrical center of the top surface of the sample; obtaining a consistent force curve and a disjunctive force curve; comparing the slopes of the three curves including the sensitivity force curve, the consistent force curve, and the disjunctive force curve; and extracting the distance between the bottom surface of the sample and the substrate. According to the invention, measurement error due to offset of a target point from the center of a sample can be eliminated without damage on the structure of a target nanometer device, thus high-resolution measurement of nanometer clearance of nanometer structures is realized.