CVD设备气流不稳定因素分析及解决方案  

Analysis and Solutions to Unsteady Gas Flow of CVD

作　　者：刘永立[1] 

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050051

出　　处：《半导体技术》2009年第2期168-171,共4页Semiconductor Technology

摘　　要：为解决CVD设备在工艺过程中有时存在工艺参数周期性波动的现象,进行了相关分析。发现使用高压钢瓶存储的高纯气态源时,常使用单个调压阀和质量流量计(MFC)来减压和控制流量。而高压差和小流量工作常会导致调压阀的周期性开启,由此产生周期性的管道压力波动。由于MFC从设计上无法完全缓冲压力波动,进而引起流量波动,造成淀积材料参数的波动。针对这一问题提出采用改变气源、增加稳压装置等作为解决方法,并归纳为三种气路改动方案。通过在一台设备上应用,将波动范围由+120%/-40%缩小至+2%/-4%。The parameters periodic changing in CVD process happened sometimes, in order to solve the problem, some investigations were carded out. And it is found that a regulator and MFC are always installed in series between high pressure gas cylinder and chamber in CVD for controlling pressure and flux, respectively. The high difference of pressure and small gas flow rate from the cylinder to the chamber will induce periodic open of the valve of the regulator, and leads to the periodic fluctuation of pipe pressure. Since the MFC can not completely relief the surge in design, it will cause the fluctuation of gas flow rate, it can result in the parameters changing of deposited layers. In order to solve the problem, changing gas source, adding transitional regulator, and using double dilution gas line are suggested. It is proved in a system, the range is reduced from ＋ 120%/- 40% to ＋ 2%/- 4%.

关 键 词：化学气相淀积 质量流量计 电子压力控制计 调压阀 

分 类 号：TN305[电子电信—物理电子学]