Patent ID: 11769799

Abstract:
The present invention provides a patterned silicon substrate-silicon germanium thin film composite structure comprising a silicon substrate having a patterned structure, a silicon germanium buffer layer positioned on the silicon substrate, a silicon germanium/silicon superlattice layer positioned on the silicon germanium buffer layer and a silicon germanium thin film layer positioned on the silicon germanium/silicon superlattice layer, wherein the silicon germanium/silicon superlattice layer comprises silicon germanium layers and silicon layers which are grown alternately. The present invention also provides a preparation method of the patterned silicon substrate-silicon germanium thin film composite structure of the present invention. The present invention also provides an application of the patterned silicon substrate-silicon germanium thin film composite structure of the present invention in strained silicon devices. The patterned silicon substrate-silicon germanium thin film composite structure provided by the present invention has low threading dislocation density and low surface roughness. A strained silicon device fabricated based on the silicon germanium thin film layer can effectively reduce the scattering of defects to carriers, thereby improving carrier mobility.