| 摘要 |
In a process for mitigating and/or eliminating the abnormal growth of underlying polysilicon in dichloro silane-based CVD polycide WSix films, a first technique conducts the deposition of the underlying polysilicon layer at a temperature that substantially avoids crystallization of the underlying polysilicon. A second approach reduces the exposure (for example time period and or concentration) of the mono-silane SiH<SB>4</SB> post flush, so as to avoid infusion of silicon into the underlying polysilicon layer, and resulting abnormal growth. In this manner, abnormal effects, such as stress fractures formed in subsequent layers, can be eliminated. The polysilicon layer is flushed with a first flush material (SiH<SB>4</SB>) to provide a transition layer and then with a second flush material (dichlorosilane (DCS)) to provide a second material layer over the polysilicon layer, which provides adherence characteristics, providing a combination of the first flush material and the second flush material to deposit a bulk second material layer (DCS-WSi<SB>x</SB>) on the transition layer. Nucleation of WSi<SB>x</SB> can occur after the second flushing. After the bulk material has been deposited it is flushed with the second flush material to remove impurities and then with the first flush material to mitigate stress between the polysilicon layer and the bulk layer.
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