Impact of Silicon Surface Roughness on Device Performance and Novel Roughness Measurement Method

Since higher performance of semiconductor devices is required, all of the semiconductor wafer manufacturers make their effort into device size reduction. However, in the latest semiconductor device, only the size reduction is not sufficient to achieve the requirement. The carrier mobility is essential to be improved. The semiconductor manufacturers, especially wet cleaning process people, try to optimize their process parameters to get smoother silicon surface. When they examine the process parameters, only Atomic Force Microscope (AFM) is available to measure the roughness of silicon surface, but the throughput of AFM is quite low. To solve this problem, we present a method of measuring silicon surface roughness called micro-haze measurement. Through experiments and a correlation analysis, we confirmed that it is sensitive enough to monitor silicon surface roughness in a much shorter time than the conventional method.