Patent ID: 7326970

Claim:
A metamorphic avalanche photodetector, comprising: a substrate; a buffer layer contacting the substrate, wherein the buffer layer has a buffer layer composition that changes with increasing distance from the substrate; an active structure deposited upon the buffer layer, wherein the active structure comprises a metamorphic absorption structure that absorbs light and responsively produces primary charge carriers, and an avalanche multiplication structure that receives the primary charge carriers from the metamorphic absorption structure and responsively produces secondary charge carriers, and wherein the avalanche multiplication structure comprises a charge layer contacting the metamorphic absorption structure, a multiplication layer contacting the charge layer, wherein the multiplication layer receives the primary charge carriers from the metamorphic absorption structure and responsively produces the secondary charge carriers, and a contact layer contacting the multiplication layer; and an output electrical contact in electrical communication with the active structure to collect at least some of the secondary charge carriers.