Patent ID: 8093582
Filing Date: 2012-01-10
Classification: B82Y,H01L

Abstract:
1. A dual band heterojunction photodetector comprising: a. at least N barriers, with N being an integer greater than or equal to one, each of said N barriers comprised of one or more Group III elements or Group V elements, and each said at least N barriers characterized by a barrier bandgap; b. at least one emitter and if N is greater than one then N emitters, each emitter comprised of one or more Group III or Group V elements doped with one or more Group II, Group IV, or Group VI elements to cause free carriers in the emitter to be responsive to optical signals and said at least one emitter characterized by an emitter bandgap different from that of the barrier bandgap, wherein each said at least one emitter is comprised of material different from that of the at least N barriers and the at least one emitter is substantially adjacent to at least one of said at least N barriers so as to form a heterojunction at each interface between an emitter and a barrier, c. a single top barrier substantially between the first contact and a third contact, said top barrier comprised of one or more Group III elements or Group V elements doped with one or more Group II, Group IV, or Group VI elements,