Infrared detector and method of detecting one or more bands of infrared radiation

Patent metadata

Field	Value
Publication number	US-9876134-B2
Application number	US-201514955302-A
Country	US
Kind code	B2
Filing date	Dec 1, 2015
Priority date	Dec 1, 2015
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

A dual-band infrared detector is provided. The dual-band infrared detector includes a first absorption layer sensitive to radiation in only a short wavelength infrared spectral band, and a barrier layer coupled to the first absorption layer. The barrier layer is fabricated from an alloy including aluminum and antimony, and at least one of gallium or arsenic. The dual-band infrared detector also includes a second absorption layer coupled to the barrier layer opposite the first absorption layer. The second absorption layer is sensitive to radiation in only a medium wavelength infrared spectral band. The composition of the alloy used to fabricate the barrier layer is selected such that valence bands of the barrier layer and the first and second absorption layers substantially align.

First claim

What is claimed is:

1. A dual-band infrared detector comprising:
a first absorption layer sensitive to radiation in only a short wavelength infrared spectral band, said first absorption layer comprising a first lattice structure having a first lattice parameter;
a barrier layer coupled to said first absorption layer, said barrier layer comprising a second lattice structure having a second lattice parameter that differs from the first lattice parameter by at least a predetermined threshold, wherein said barrier layer is fabricated from an alloy comprising aluminum and antimony, and at least one of gallium or arsenic; and
a second absorption layer coupled to said barrier layer opposite said first absorption layer, said second absorption layer sensitive to radiation in only a medium wavelength infrared spectral band, wherein the composition of the alloy used to fabricate said barrier layer is selected such that valence bands of said barrier layer and said first and second absorption layers substantially align.

2. The dual-band infrared detector in accordance with claim 1 , wherein said barrier layer comprises Al 0.97 Ga 0.03 Sb.

3. The dual-band infrared detector in accordance with claim 1 further comprising at least one grading layer positioned between said first absorption layer and said barrier layer.

4. The dual-band infrared detector in accordance with claim 1 , wherein said first absorption layer is sensitive to wavelengths within a range between about 1 micrometer and about 2.5 micrometers.

5. The dual-band infrared detector in accordance with claim 1 , wherein said second absorption layer is sensitive to wavelengths within a range between about 3.0 micrometers and about 5 micrometers.

6. The dual-band infrared detector in accordance with claim 1 , wherein said first absorption layer is fabricated from an alloy comprising indium, gallium, and arsenic.

7. The dual-band infrared detector in accordance with claim 1 , wherein said second absorption layer is fabricated from an alloy comprising indium, arsenic, and antimony.

8. The dual-band infrared detector in accordance with claim 1 , wherein said barrier layer is fabricated from a p-type semiconductor material.

9. The dual-band infrared detector in accordance with claim 8 , wherein the p-type semiconductor material of said barrier layer is doped with at least one of silicon or beryllium.

10. The dual-band infrared detector in accordance with claim 1 further comprising:
at least one buffer layer coupled on an opposing side of said first absorption layer from said barrier layer; and
a substrate coupled to said at least one buffer layer.

11. An imaging system comprising:
a readout integrated circuit; and
a dual-band infrared detector electrically coupled to said readout integrated circuit, wherein said dual-band infrared detector comprises:
a first absorption layer sensitive to radiation in only a short wavelength infrared spectral band, said first absorption layer comprising a first lattice structure having a first lattice parameter;
a barrier layer coupled to said first absorption layer, said barrier layer comprising a second lattice structure having a second lattice parameter that differs from the first lattice parameter by at least a predetermined threshold, wherein said barrier layer is fabricated from an alloy comprising aluminum and antimony, and at least one of gallium or arsenic; and
a second absorption layer coupled to said barrier layer opposite said first absorption layer, said second absorption layer sensitive to radiation in only a medium wavelength infrared spectral band, wherein the composition of the alloy used to fabricate said barrier layer is selected such that valence bands of said barrier layer and said first and second absorption layers substantially align,
wherein said readout integrated circuit is configured to selectively apply a bias voltage to said dual-band infrared detector.

12. The imaging system in accordance with claim 11 , wherein said barrier layer comprises Al 0.97 Ga 0.03 Sb.

13. The imaging system in accordance with claim 11 , wherein said first absorption layer is fabricated from an alloy comprising indium, gallium, and arsenic.

14. The imaging system in accordance with claim 11 , wherein said second absorption layer is fabricated from an alloy comprising indium, arsenic, and antimony.

15. The imaging system in accordance with claim 11 , wherein said barrier layer is fabricated from a p-type semiconductor material.

16. The imaging system in accordance with claim 15 , wherein the p-type semiconductor material of said barrier layer is doped with at least one of silicon or beryllium.

17. A method of detecting multiple bands of infrared radiation, said method comprising:
selectively applying bias voltages to a dual-band infrared detector including a first absorption layer, a barrier layer coupled to the first absorption layer, and a second absorption layer coupled to the barrier layer, the first absorption layer sensitive to radiation in only a short wavelength infrared spectral band and the second absorption layer sensitive to radiation in only a medium wavelength spectral band, wherein the barrier layer is fabricated from an alloy including aluminum and antimony, and at least one of gallium or arsenic, and the composition of the alloy is selected such that valence bands of the first absorption layer and the barrier layer substantially align;
receiving a first electrical signal from the dual-band infrared detector when a bias voltage having a first polarity is applied thereto, the first electrical signal corresponding to detection of radiation in the short wavelength infrared spectral band; and
receiving a second electrical signal from the dual-band infrared detector when a bias voltage having a opposite second polarity is applied thereto, the second electrical signal corresponding to detection of radiation in the medium wavelength infrared spectral band.

18. The method in accordance with claim 17 , wherein selectively applying bias voltages comprises applying the bias voltages to the dual-band infrared detector sequentially.

19. The method in accordance with claim 17 further comprising selectively applying the bias voltage to the first absorption layer sensitive to wavelengths within a range between about 1 micrometer and about 2.5 micrometers.

20. The method in accordance with claim 17 further comprising selectively applying the bias voltage to the second absorption layer sensitive to wavelengths within a range between about 3.0 micrometers and about 5 micrometers.

Assignees

• Boeing Co

Inventors

• De Lyon Terence J
• Terterian Sevag
• Sharifi Hasan

Classifications

• H01L27/1443

  Electricity · mapped topic

• H01L31/035281

  Electricity · mapped topic

• H01L31/03042

  Electricity · mapped topic

• H01L31/03046

  Electricity · mapped topic

• H01L31/109 Primary

  Electricity · mapped topic