INTERBAND CASCADE DEVICES

摘要

Photovoltaic (PV) and photodetector (PD) devices, comprising a plurality of interband cascade (IC) stages, wherein the IC stages comprise an absorption region with a type-I superlattice and/or a bulk semiconductor material having a band gap, the absorption region configured to absorb photons, an intraband transport region configured to act as a hole barrier, and an interband tunneling region configured to act as an electron barrier, wherein the absorption region, the intraband transport region, and the interband tunneling region are positioned such that electrons will flow from the absorption region to the intraband transport region to the interband tunneling region.

主权项

1. An interband cascade (IC) device, comprising:
a plurality of IC stages, wherein at least one of the IC stages comprises:
a conduction band and a valence band;an absorption region comprising at least one of a Type-I superlattice and a direct band gap semiconductor bulk material with a first band gap, the absorption region configured to absorb photons;an intraband transport region configured to act as a hole barrier and coupled to the absorption region, wherein the intraband transport region has a second band gap that is greater than the first band gap; andan interband tunneling region configured to act as an electron barrier and coupled to the absorption region, wherein the interband tunneling region has a third band gap that is greater than the first band gap, and wherein the interband tunneling region is coupled to an adjacent intraband transport region of an adjacent IC stage via a type II heterointerface, wherein the absorption region is positioned between the intraband transport region and the interband tunneling region; wherein the interband tunneling region is configured such that:
electrons in the conduction band flow from the absorption region to the intraband transport region in a first direction away from the interband tunneling region,the interband tunneling region suppresses the electrons from flowing in a second direction opposite from the first direction, andholes in the valence band flow from the absorption region toward the interband tunneling region; and wherein the plurality of IC stages is configured so that the electrons flow from the absorption region to the intraband transport region then flow into an adjacent valence band of the adjacent IC stage.