| dc.description.abstract | Because the current inspection instruments cannot measure the roughness of the inner and outer layers of the wafer at the same time, and have other shortcomings that are not good for the factory, Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM) For example, the common thing is that the measurement speed is slow and time-consuming, the machine is large and the power consumption is also required, and the risk of the wafer may be scratched or damaged, and the research purpose of this paper is mainly to improve Measurement efficiency and accuracy, reduce measurement time, and solve contact and destructive measurement methods, as well as support wafers of different sizes or single local regional measurements.
This study uses a two-dimensional electronic sensor to measure wafer roughness, and uses the high input impedance of the operational amplifier to eliminate the offset voltage and reduce the output error. The principle of this study is Use the signal generator to generate an equipotential waveform to form an equipotential field on the surface of the wafer. When the height of the wafer surface is different, the equipotential field will shift, and then there are two points in the X and Y directions. The five-point probe sensor is used to measure the potential and the difference between (X, -X) and (Y, -Y). The electric field generated by the point charge is inversely proportional to the square of the distance, and then the wafer is calculated. The roughness, and the status of each area will also be displayed on the oscilloscope X, Y graph, and record graphs are stored, ΔX and ΔY are the maximum roughness of each axis.
Keyword：Detector, rough measurement, offset voltage, potential difference | en_US |