Enhanced phase stability and morphological stability of Ni(Si,Ge) on strained Si 0.8Ge 0.2

Abstract

NiSi 0.8Ge 0.2 film formed on a strained Si 0.8Ge 0.2 layer epitaxially grown on a Si(100) substrate wafer is morphologically stable up to 750 °C. The NiSi 0.8Ge 0.2 film is found to be strongly oriented along its 〈010〉 direction. This remarkable stability is thus possibly caused by the tendency of an epitaxial alignment between the NiSi 0.8Ge 0.2 film and the Si 0.8Ge 0.2 layer. The presence of Ge in NiSi forming the ternary solution NiSi 0.8Ge 0.2 hinders the formation of NiSi 2 even at 850 °C.