一、引言半导体硅是电子工业发展的重要基础材料之一,其质量决定着电子工业发展的水平,对实现四个现代化起着关键作用。当前硅材料制备工艺已很成熟,质量达到相当高的水平,已能满足功率元件,各种晶体管,集成电路及大规模集成电路的要求。由于超 I. INTRODUCTION Semiconductor silicon is one of the important basic materials for the development of the electronics industry. Its quality determines the level of development of the electronics industry and plays a key role in the realization of the four modernizations. The current silicon material preparation process is very mature, the quality reached a very high level, has been able to meet the power components, a variety of transistors, integrated circuits and large scale integrated circuit requirements. Due to ultra