Lateral interband type II engineered (LITE) detector
A lateral interband Type II engineered (LITE) detector is provided. LITE detectors use engineered heterostructures to spatially separate electrons and holes into separate layers. The device may have two configurations, a positive intrinsic (PIN) configuration and a BJT (Bipolar junction transistor) configuration. The PIN configuration may have a wide bandgap (WBG) layer that transports the holes above a narrow bandgap (NBG) absorber layer that absorbs the target radiation and transports the electrons. The BJT configuration may have a WBG layer operating as a BJT above an NBG layer. In both configurations, the LITE design uses a Type II staggered offset between the NBG layers and the WBG layers that provides a built-in field for the holes to drift from an absorber region to a transporter region.
1. A lateral interband semiconductor device comprising:
a substrate comprising InAs or InP defining a bottom surface of the lateral interband semiconductor device;
a narrow bandgap semiconductor (NBG) layer disposed on the substrate, the NBG layer comprising a first binary semiconductor material, a first ternary semiconductor material, or a first quaternary semiconductor material;
a wide bandgap semiconductor (WBG) layer disposed on the NBG layer, the WBG layer comprising a second binary semiconductor material, a second ternary semiconductor material, or a second quaternary semiconductor material, wherein the NBG layer and the WBG layer define a staggered offset therebetween that spatially separate electrons or holes using a built-in field;
a positive terminal defining a first upper side surface of the lateral interband semiconductor device; and
a negative terminal opposite the positive terminal, the negative terminal defining a second upper side surface of the lateral interband semiconductor device.
2. The device of claim 1 , wherein the WBG layer and the NBG layer comprise one or more of superlattice III-V semiconductors, group IV semiconductors, or group II-VI semiconductors.
3. The device of claim 1 , wherein the built-in field is caused by one or more of a Type I, Type II, or Type III band lineup between the WBG layer and the NBG layer.
4. The device of claim 1 , wherein the built-in field is caused by controlling a type and an amount of doping in the WBG layer and the NBG layer.
5. The device of claim 1 , further comprising a spacer layer between the WBG layer and the NBG layer.
6. The device of claim 1 , further comprising a plurality of additional alternating WBG layers and NBG layers.
7. The device of claim 1 , wherein the device is a photodetector.
8. The device of claim 1 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected to maximize a signal-to-noise ratio without internal gain during photocurrent generation.
9. The device of claim 1 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected to maximize a signal-to-noise ratio with internal gain during photocurrent generation.
10. The device of claim 1 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected to include bipolar junction transistor (BJT) internal gain during photocurrent generation.
11. The device of claim 1 , wherein the WBG layer is made of an indirect material so that photon absorption takes place only in the NBG layer.
12. The device of claim 1 , wherein the WBG layer is made of a direct material so that photon absorption takes place both in the WBG layer and the NBG layer.
13. The device of claim 1 , further comprising a mask that limits where photon absorption occurs on the device.
14. The device of claim 1 , wherein the WBG and NBG layers have a layer composition, a layer thickness, and a background doping selected to optically confine one or more photons in the NBG layer.
15. The device of claim 1 , wherein the NBG layer is thinner than the WBG layer.
16. The device of claim 1 , further comprising an additional WBG layer between the NBG layer and the substrate.
17. A lateral interband semiconductor device comprising:
a substrate comprising InAs or InP defining a bottom surface of the lateral interband semiconductor device;
a narrow bandgap semiconductor (NBG) layer disposed on the substrate, the NBG layer comprising a first binary semiconductor material, a first ternary semiconductor material, or a first quaternary semiconductor material;
a wide bandgap semiconductor (WBG) layer disposed on the NBG layer, the WBG layer comprising a second binary semiconductor material, a second ternary semiconductor material, or a second quaternary semiconductor material, wherein the NBG layer, the WBG layer, define a staggered offset therebetween that spatially separate electrons or holes using a built-in and applied field;
a positive terminal defining a first upper side surface of the lateral interband semiconductor device; and
a negative terminal opposite the positive terminal, the negative terminal defining a second upper side surface of the lateral interband semiconductor device; and
an independent terminal connected to the WBG layer that is configured to generate a field that reduces spatial separation of the electrons or holes.
18. The device of claim 17 , wherein the built-in field is caused by one or more of a Type I, Type II, or Type III band lineup between the WBG layer and the NBG layer.
19. The device of claim 17 , wherein the WBG layer and the NBG layer comprise one or more of superlattice III-V semiconductors, group IV semiconductors, or group II-VI semiconductors.
20. The device of claim 17 , wherein the built-in field is caused by controlling a type and an amount of doping in the WBG layer and the NBG layer.
21. The device of claim 17 , further comprising a spacer layer between the WBG layer and the NBG layer.
22. The device of claim 17 , further comprising a plurality of additional alternating WBG layers and NBG layers.
23. The device of claim 17 , further comprising a positive terminal and a negative terminal.
24. The device of claim 17 , wherein the device is a photodetector.
25. The device of claim 17 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected to maximize a signal-to-noise ratio without internal gain during photocurrent generation.
26. The device of claim 17 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected to maximize a signal-to-noise ratio with internal gain during photocurrent generation.
27. The device of claim 17 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected for photovoltaic generation.
28. The device of claim 17 , wherein the NBG layer and the WBG layer have a composition, a thickness, a lateral dimension, and a doping that is selected to include bipolar junction transistor (BJT) internal gain during photocurrent generation.
29. The device of claim 17 , wherein the WBG layer is made of an indirect material so that photon absorption takes place only in the NBG layer.
30. The device of claim 17 , wherein the WBG layer is made of a direct material so that photon absorption takes place both in the WBG layer and the NBG layer.
31. The device of claim 17 , further comprising a mask that limits where photon absorption occurs on the device.
32. The device of claim 17 , wherein the WBG and NBG layers have a layer composition, a layer thickness, and a background doping selected to optically confine one or more photons in the NBG layer.
33. The device of claim 17 , wherein the NBG layer is thinner than the WBG layer.
34. The device of claim 17 , further comprising an additional WBG layer between the NBG layer and the substrate.