Method for controlling dislocation positions in silicon germanium buffer layers

Abstract

A method for controlling dislocation position in a silicon germanium buffer layer located on a substrate includes depositing a strained silicon germanium layer on the substrate and irradiating one or more regions of the silicon germanium layer with a dislocation inducing agent. The dislocation inducing agent may include ions, electrons, or other radiation source. Dislocations in the silicon germanium layer are located in one or more of the regions. The substrate and strained silicon germanium layer may then be subjected to an annealing process to transform the strained silicon germanium layer into a relaxed state. A top layer of strained silicon or silicon germanium may be deposited on the relaxed silicon germanium layer. Semiconductor-based devices may then be fabricated in the non-damaged regions of the strained silicon or silicon germanium layer. Threading dislocations are confined to damaged areas which may be transformed into SiOisolation regions.