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

The effect of CESL stressor on the morphological stability of the Pt-dissolved NiSi_1-xGe_x films formed on Si_0.72Ge_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 NiSi_1-xGe_x films still increases with the stress boost from the CESL stressor due to the film agglomeration occurring at 400°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 NiSi_1-xGe_x films. The stressor-induced morphological instability may bring about the integration issue but can be mitigated by an intercalated Si layer between the NiSi_1-xGe_x film and Si_0.72Ge_0.28.