Micro Cantilever Movement Detection with an Amorphous Silicon Array of Position Sensitive Detectors

The movement of a micro cantilever was detected via a self constructed portable data acquisition prototype system which integrates a linear array of 32 1D amorphous silicon position sensitive detectors (PSD). The system was mounted on a microscope using a metal structure platform and the movement of the 30 mu m wide by 400 mu m long cantilever was tracked by analyzing the signals acquired by the 32 sensor array electronic readout system and the relevant data algorithm. The obtained results show a linear behavior of the photocurrent relating X and Y movement, with a non-linearity of about 3%, a spatial resolution of less than 2 mu m along the lateral dimension of the sensor as well as of less than 3 mu m along the perpendicular dimension of the sensor, when detecting just the micro-cantilever, and a spatial resolution of less than 1 mu m when detecting the holding structure.