CESL-Stressor-Induced Morphological Instability of Pt-Dissolved Ni Germanosilicide Formed on Silicon Germanium Epilayer

摘要

The effect of CESL stressor on the morphological stability of the Pt-dissolved $hbox{NiSi}_{1 - x}hbox{Ge}_{x}$ films formed on $ hbox{Si}_{0.72}hbox{Ge}_{0.28}$ is demonstrated for the first time. In the CESL stress range studied, no high-resistivity phase is found in the silicide layer, but the $R_{S}$ of the $hbox{NiSi}_{1 - x}hbox{Ge}_{x}$ films still increases with the stress boost from the CESL stressor due to the film agglomeration occurring at 400 $^{circ}hbox{C}$. The tensile CESL stress results in a much steeper trend in the $R_{S}$ increases than the compressive one, which can be connected to the stressor-induced interface energy change manifested by the morphological observation on the film breaches of discrete $hbox{NiSi}_{1 - x}hbox{Ge}_{x}$ films. The stressor-induced morphological instability may bring about the integration issue but can be mitigated by an intercalated Si layer between the $hbox{NiSi}_{1 - x} hbox{Ge}_{x}$ film and $hbox{Si}_{0.72}hbox{Ge}_{0.28}$ .