本文报道了低压化学气相淀积（ＬＰＣＶＤ）制备的多晶硅薄膜内应力与制备条件、退火温度和时间及掺杂浓度关系的实验研究结果，用ＸＲＤ、ＲＥＤ等技术测量分析了多晶硅膜的微结构组成．结果表明，ＬＰＣＶＤ制备的多晶硅薄膜具有本征压应力，其内应力受淀积条件、微结构组成等因素的影响．采用快速退火（ＲＴＡ）可以使其压应力松弛，减小其内应力，并可使其转变成为本征张应力，以满足在微机电系统（ＭＥＭＳ）制备中的要求． In this paper, the experimental results of the relationship between the internal stress of polycrystalline silicon thin films prepared by low pressure chemical vapor deposition (LPCVD) and the preparation conditions, annealing temperature and time and the doping concentration were reported. The microstructure of polycrystalline silicon films . The results show that the polycrystalline silicon films prepared by LPCVD have intrinsic compressive stress, and the internal stress is affected by the deposition conditions, the microstructure and other factors. Rapid annealing (RTA) can relax its compressive stress, reduce its internal stress, and transform it into intrinsic tensile stress to meet the requirements of micro-electromechanical systems (MEMS) fabrication.