薄膜厚度测量是ＶＬＳＩ生产工艺中不可缺少的重要工序，也是保证产品质量提高生产效率的重要手段。采用显微镜－全息凹面光栅－ＣＣＤ－微机处理的测量系统具有结构简单工作可靠的特点。本文介绍了其原理与特点，并对该系统进行了实验，实验结果表明，对于较薄的膜层测量精度为±２ｎｍ，对于一般膜层为被测膜层厚度的±２％－±５％。 Film thickness measurement is an indispensable important process in VLSI production process, and also an important means to ensure product quality and improve production efficiency. The use of microscope - holographic concave grating - CD-PC-based measurement system has the characteristics of simple structure and reliable work. The principle and characteristics of this system are introduced in this paper. Experiments on this system are carried out. The experimental results show that the measurement accuracy is ± 2nm for the thinner film and ± 2% to ± 5% of the thickness of the film to be measured. .