一、引言众所周知,用GaAs制作MOSFET,在速度方面比用Si要优越得多,这是因为电子在GaAs中的迁移率是在Si中的五倍以上,而且GaAs的禁带宽度比Si的宽。早在1967年,已做出了几百兆周的GaAs MOSFET[1,2]。但是,后来的发展很慢。其根本原因在于很难做出具有良好界面性能的缘绝层。另外,还因为出现了高性能的微波GaAs MESFET, I. INTRODUCTION It is well known that MOSFETs made from GaAs are far superior in speed to Si because the mobility of electrons in GaAs is more than five times that of Si and the bandgap of GaAs is wider than that of Si . As early as 1967, a few hundred megabits of GaAs MOSFETs have been made [1,2]. However, later development was slow. The fundamental reason is that it is difficult to make a margin layer with good interfacial properties. In addition, but also because of the emergence of high-performance microwave GaAs MESFET,