Patent ID: 7071087

Claim:
A process to grow ZnSe film on Si substrate, comprising: (1) providing a clean flat Si substrate; (2) growing a first SiGe epitaxital layer with a given thickness to contain a large amount of threading dislocation created by lattice dislocation at the bottom of the layer and interfaces; (3) performing high temperature annealing to the first SiGe epitaxital layer in situ to reduce threading dislocation density; (4) growing a second and optionally a third SiGe epitaxital layer to terminate the threading dislocation propagating upward from the first epitaxital layer with the produced strained interfaces, and performing high temperature annealing in situ during both growing periods; (5) growing a pure Ge layer on the surface of the top epitaxital layer obtained in step (4); and (6) eventually growing a ZnSe layer on the pure Ge layer.