Patent ID: 6508110
Filing Date: 2003-01-21
Classification: B82Y,G01Q,Y10S

Abstract:
An atomic force microscope comprising:a probe having an end fixed to a piezoelectric oscillator on a seat and having a probe tip at another end arranged proximately to a surface of a slice to be scanned, said probe being driven to scan over a surface of the slice; a sinusoidal wave generator for producing sinusoidal wave signals and sending said sinusoidal wave signals to said piezoelectric oscillator so that said piezoelectric oscillator generates an oscillation similar to a sinusoidal wave, and further said probe also generates a vibration like a sinusoidal wave; a phase-lock loop for locking frequency and phase of said sinusoidal wave signal generated by said sinusoidal wave generator to produce a pulse modulation signal with the same frequency as that of said probe; a laser unit for receiving said pulse modulation signal generated by said phase-lock loop and outputting pulsed laser beams; the pulsed laser beams being emitted to a back side of the probe and then being reflected therefrom; a photo detector for receiving reflected laser beams from said back side of said probe and outputting a current signal corresponding to the intensity of said laser beam; a current to voltage converter for converting said current signal sent by said photo detector into a voltage signal; an operation amplifying circuit for calculating and amplifying each voltage signal output from said current to voltage converter; a low pass filter for low-pass filtering said output signal from the operation amplifying circuit for acquiring a voltage value corresponding to an amplitude of the vibration of said probe; a Z-axis servo controller for receiving a voltage value corresponding to an amplitude of a vibration of said probe output from the low pass filter and then generating a corresponding control command through an operation base on a control algorithm for controlling upward and downward movements of said seat so as to keep an amplitude of the vibration of said probe in a predetermined value; a scanned image data storage device for storing image data of each data point collected by scanning the surface of said slice with said probe; an image data processor for processing said stored image data; and a display for displaying processed image data.