Measuring and testing – Surface and cutting edge testing – Roughness
Patent
1993-07-02
1994-07-19
Noland, Thomas P.
Measuring and testing
Surface and cutting edge testing
Roughness
250307, G01B 2130
Patent
active
053298080
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 of 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. At the same time, the instrument can determine the topography of the sample with nanometer resolution. In an alternate embodiment, the lever is connected to a separate piezoelectric driver to vary the force on the tip. This improved AFM can also be used to periodically reset the force at which the tip contacts the sample and quickly replace the tip on the sample in the event that the tip loses contact with the surface.
REFERENCES:
patent: Re34331 (1993-08-01), Elings et al.
patent: 4724318 (1988-02-01), Binnig
patent: 4823004 (1989-04-01), Kaiser et al.
patent: 4848141 (1989-07-01), Oliver et al.
patent: 4935634 (1990-06-01), Hansma et al.
patent: 5051646 (1991-09-01), Elings et al.
patent: 5162653 (1992-11-01), Hosaka et al.
patent: 5189906 (1993-03-01), Elings et al.
patent: 5193383 (1993-03-01), Burnham et al.
patent: 5212987 (1993-05-01), Dransfeld et al.
patent: 5229606 (1993-07-01), Elings et al.
"Measuring the nanomechancal properties and surface forces of materials using an atomic force microscope"; J. Vac. Sci. Technol. A; vol. 7, No. 4 Jul./Aug. 1989, pp. 2906-2913; Nancy A. Barnham et al.
Elings Virgil B.
Gurley John A.
Digital Instruments, Inc.
Noland Thomas P.
LandOfFree
Atomic force microscope does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Atomic force microscope, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Atomic force microscope will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-512709