一、概述自从集成电路(IC)问世以来,集成规模连续不断地加大,从小规模至中规模,又至大规模集成(LSI),最近又进至超大规模集成(VLSI).这是由于材料工艺和信号处理技巧的飞速改进以及计算机辅助设计的充分利用等,使得固态电子学迅猛地朝微电子学方向发展,从而导致成本低廉和运用可靠的VLSI微电子电路的 I. INTRODUCTION Since the advent of integrated circuits (ICs), the scale of integration has been continuously increasing from small scale to medium scale to large scale integration (LSI) and recently to very large scale integration (VLSI) The rapid improvements in process and signal processing techniques and the full use of computer-aided design have led to the rapid development of solid-state electronics toward microelectronics, resulting in low cost and reliable use of VLSI microelectronic circuits