Diode barrier infrared detector devices and barrier superlattice structures
View Patent ↗Diode barrier infrared detector devices and superlattice barrier structures are disclosed. In one embodiment, a diode barrier infrared detector device includes a first contact layer, an absorber layer adjacent to the first contact layer, and a barrier layer adjacent to the absorber layer, and a second contact layer adjacent to the barrier layer. The barrier layer includes a diode structure formed by a p-n junction formed within the barrier layer. The barrier layer may be such that there is substantially no barrier to minority carrier holes. In another embodiment, a diode barrier infrared detector device includes a first contact layer, an absorber layer adjacent to the first contact layer, a barrier layer adjacent to the absorber layer, and a diode structure adjacent to the barrier layer. The diode structure includes a second contact layer.
1. A diode barrier infrared detector device utilizing a p-type absorber comprising:
a first contact layer, wherein the first contact layer is doped p-type;
an absorber layer adjacent to the first contact layer, wherein the absorber layer is doped p-type;
a barrier layer adjacent to the absorber layer;
a p-type material layer adjacent to the barrier layer; and
a second contact layer adjacent to the p-type material layer, wherein the second contact layer is n-doped.
2. The diode barrier infrared detector device of claim 1 , wherein the p-type material layer and the second contact layer comprise a material having a wider bandgap than a material of the absorber layer.
3. The diode barrier infrared detector device of claim 1 , further comprising a nominally undoped i region disposed between the p-type material layer and the second contact layer.
4. The diode barrier infrared detector device of claim 1 , further comprising a nominally undoped graded gap section disposed between the p-type material layer and the second contact layer.
5. The diode barrier infrared detector device of claim 4 , wherein a bandgap of the undoped graded gap section is varied from a bandgap of the p-type material layer to a bandgap of the second contact layer.
6. The diode barrier infrared detector device of claim 1 , wherein the absorber layer is an InAs/InAsSb superlattice structure.
7. The diode barrier infrared detector device of claim 1 , wherein the p-type material layer and the second contact layer form a p-n junction.
8. The diode barrier infrared detector device of claim 7 , wherein a p-doping profile within the p-n junction region is such that a conduction band edge of the p-type material layer is higher than a conduction band edge of the absorber layer.