Cantilever deflection sensor and use thereof
AssigneeInternational Business Machines Corporation
InventorsJean-Philippe M. Bourgoin, Matthew B. Johnson, Bruno Michel
Life of this patent
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Abstract
A new method and an apparatus for measuring the deflection of or the force exerted upon a cantilever-type micromechanical element is presented which is based on detecting radiation emitted from the gap between the cantilever (220) and a second surface (230, 231). The radiation, while occurring spontaneously at high frequencies when appropriately biasing the cantilever and the second surface by a voltage, can be enlarged by using external energy sources. The new method and apparatus is also applied to surface investigation, particularly to dopant profiling.
Claims20
An apparatus for measuring a force exerted upon or a deflection of a flexible cantilever used in atomic force microscopy, comprising means for providing a single high fundamental frequency signal w between the flexible cantilever and a second surface, antenna means for receiving radiation produced during atomic force microscopy of a sample using said cantilever, amplifying means for detecting from the radiation received by the antenna a higher harmonic nw of the fundamental frequency and generating a signal therefrom for use to measure a characteristic of the sample, and means to apply in operation a DC voltage to said cantilever.
A method for measuring a force exerted upon or a deflection of a flexible cantilever used in atomic force microscopy, comprising steps of:
- generating a single high frequency radiation signal w from a single source in a gap between said cantilever and a second surface during the performance of atomic force microscopy on a sample, receiving and amplifying a higher harmonic nw of the single high frequency signal of said radiation signal w and determining physical characteristics of the sample using the higher harmonic.
An apparatus for measuring a force exerted upon or a deflection of a flexible cantilever used in atomic force microscopy, comprising antenna means for receiving radiation produced during atomic force microscopy of a sample using said cantilever, amplifying means for detecting the antenna output and generating a signal therefrom, a cavity with conductive walls enclosing the cantilever, with one of said walls being moveable relative to the others, and means to apply in operation a DC voltage to said cantilever.
An apparatus for use as a dopant profiler by measuring a force exerted upon or a deflection of a flexible cantilever used in atomic force microscopy, comprising the antenna means for receiving radiation produced during atomic force microscopy of a sample using said cantilever, amplifying means for detecting the antenna output and generating a signal therefrom, magnetic or piezoelectric actuator means for controlling the distance between the cantilever and a surface of the sample, force detection means for measuring the deflection of the cantilever, switchable feedback means for controlling said actuator means, said feedback means being switchable to said force detection means or to the output of the amplifying means, and means to apply in operation a DC voltage to said cantilever.
An apparatus for use as a dopant profiler by measuring a force exerted upon or a deflection of a flexible cantilever used in atomic force microscopy, comprising antenna means for receiving radiation produced during atomic force microscopy of a sample using said cantilever, amplifying means for detecting the antenna output and generating a signal therefrom, a magnetic or piezoelectric actuator means for controlling the distance between the cantilever and a surface of the sample, means for detecting a tunnel current between a tip of the cantilever and the sample, force detection means for measuring the deflection of the cantilever, switchable feedback means for controlling said actuator means, said feedback means being switchable to said tunnel current, to said force detection means, or to the output of the amplifying means, and means to apply in operation a DC voltage to said cantilever.
Dependencies are inferred from the claim text.