摘要
研究并讨论了在WSix制备的前清洗中,用气态氟化氢(HF)清洗时,多晶硅表面有从其体内析出的含磷物,这种析出物很容易跟气态HF中的微量水汽结合,形成HPO3晶体。这样的晶体在Si片表面不容易被检测到,却可以很大程度地影响芯片的良率。本系统观测了这一现象,解释了这种失效的机制,并且给出这种失效模式的解决方案。
A failure mechanism during WSix pre clean was researched and discussed. The P atoms in doped polysilicon diffuse out and oxidize in the air. They combine with the water vapor to form HPO3 crystal. These defects can＇t be removed during VHF clean and are covered by the WSix film. This can induce severe yield loss. The failure mechanism was demonstrated for the first time and an improvement methods of WSix pre clean process were given.
出处
《半导体技术》
CAS
CSCD
北大核心
2008年第3期245-247,256,共4页
Semiconductor Technology
关键词
硅化钨沉积
磷析出
沉积前清洗
WSix deposition
P out diffuse
pre clean for deposition
