PLANARIZATION OF EPITAXIAL HETEROSTRUCTURES INCLUDING THERMAL TREATMENT

摘要

A method of planarization of an epitaxial heterostructure comprising at least a strain-relaxed buffer layer epitaxially grown on a substrate of a different material, said method comprising: - a step of thermal annealing the epitaxial heterostructure at a temperature of at least 900 °C for a period of at least 2 hours, and - a step of chemical-mechanical polishing the surface of the strain-relaxed buffer layer. This method provides a specific thermal treatment which allows, by improving the relaxation of the strain-relaxed buffer layer, to obtain a better quality of the surface planarization and to insure a stable material for further processing.