200 mm硅外延片时间雾的产生机理及管控方法研究

Study on Generation Mechanism and Control Method of Time-Dependent Haze on 200 mm Silicon Epitaxial Wafer

针对硅外延加工过程及所处环境,研究了200 mm硅外延片时间雾产生的原因,分析了环境湿度、外延反应前后排外能力以及洁净厂房环境阳离子浓度等影响因素,提出了硅外延反应副产物氯化氢(HCl)和环境中的阳离子是导致硅外延片表面产生时间雾的主要原因。通过增强硅外延设备排外能力降低环境中的阳离子浓度,可有效降低时间雾产生的概率。

Based on the process and the environment of silicon epitaxy,the causes of time-dependent haze on 200 mm silicon epitaxial wafer are studied,and the influencing factors such as environmental humidity,exclusion ability before and after epitaxial reaction and environmental cation concentration in clean workshop are analyzed.The HCl,a by-product of silicon epitaxy reaction,and cations in the environment are the main causes of the time-dependent haze on the surface of silicon epitaxial wafer.The probability of time-dependent haze formation can be effectively reduced by enhancing the exclusion ability of silicon epitaxy equipment and reducing the concentration of cations in the environment.