METHODS OF FORMING DEFECT-FREE SRB ONTO LATTICE-MISMATCHED SUBSTRATES AND DEFECT-FREE FINS ON INSULATORS

摘要

A strain-relieved buffer is formed by forming a first silicon-germanium (SiGe) layer directly on a surface of a bulk silicon (Si) substrate. The first SiGe layer is patterned to form at least two SiGe structures so there is a space between the SiGe structures. An oxide is formed on the SiGe structures, and the SiGe structures are mesa annealed. The oxide is removed to expose a top portion of the SiGe structures. A second SiGe layer is formed on the exposed portion of the SiGe structures so that the second SiGe layer covers the space between the SiGe structures, and so that a percentage Ge content of the first and second SiGe layers are substantially equal. The space between the SiGe structures is related to the sizes of the structures adjacent to the space and an amount of stress relief that is associated with the structures.