GROUP III-NITRIDE GROWTH ON SILICON OR SILICON GERMANIUM SUBSTRATES AND METHOD AND DEVICES THEREFOR

摘要

A structure including a Si_1-xGe_x substrate and a distributed Bragg reflector layer disposed directly onto the substrate. The distributed Bragg reflector layer includes a repeating pattern that includes at least one aluminum nitride layer and a second layer having the general formula Al_yGa_1-yN. Another aspect of the present invention is various devices including this structure. Another aspect of the present invention is directed to a method of forming such a structure comprising providing a Si_1-xGe_x substrate and depositing a distributed Bragg reflector layer directly onto the substrate. Another aspect of the present invention is directed to a photodetector or photovoltaic cell device, including a Si_1-xGe_x substrate device, a group III-nitride device and contacts to provide a conductive path for a current generated across at least one of the Si_1-xGe_x substrate device and the group III-nitride device upon incident light.