Abstract
The atomic force microscope (AFM) has been widely used for research of nanotechnorogy. for instruments Recently, we analyzed machine immitance of the comb-drive actuator, and observed clear nonlinear characteristic of the machine admittance near the resonance frequency. We made a probe with comb-drive actuator. When the probe touched to the substrate, we found out that the mechanical immitance characteristics near the resonance changed. It is possible to make a device, it is able to measured ruggedness image using that characteristic. In addition, we observed self-oscillation in this device with a circuit make a positive feedback loop. This is same as characteristic of a crystal oscillator. Self oscillation frequency of comb-drive actuator is change when the probe touched the opposing substrate. We make a PID control circuit for control a stage, therefore the probe was hold soft contact position with opposing substrate. While the probe hold this position, it scan XY plane, we observe ruggedness image.
