Semiconductor ultraviolet (UV)photo-detecting device

Patent metadata

Field	Value
Publication number	US-9786805-B2
Application number	US-201615168159-A
Country	US
Kind code	B2
Filing date	May 30, 2016
Priority date	Sep 25, 2013
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

An ultraviolet (UV) photo-detecting device, including: a substrate; a first nitride layer disposed on the substrate; a second nitride layer disposed between the first nitride layer and the substrate; a light absorption layer disposed on the first nitride layer; and a Schottky junction layer disposed on the light absorption layer.

First claim

What is claimed is:

1. An ultraviolet photo-detecting device, comprising:
a substrate;
a first nitride layer disposed on the substrate;
a second nitride layer disposed between the first nitride layer and the substrate;
a light absorption layer disposed on the first nitride layer;
a low-current blocking layer interposed between the light absorption layer and the first nitride layer, the low-current blocking layer comprising a multiplayer structure; and
a Schottky junction layer disposed on the light absorption layer.

2. The ultraviolet photo-detecting device of claim 1 , wherein the first nitride layer has a greater thickness than the light absorption layer.

3. The ultraviolet photo-detecting device of claim 1 , wherein the first nitride layer comprises gallium nitride (GaN) and the light absorption layer comprises aluminum gallium nitride (AlGaN).

4. The ultraviolet photo-detecting device of claim 1 , wherein the multilayer structure of the low-current blocking layer comprises at least one of binary, ternary, and quaternary nitride layers comprising (Al, In, Ga)N.

5. The ultraviolet photo-detecting device of claim 1 , wherein the multilayer structure of the low-current blocking layer comprises at least two alternately stacked nitride layers having different composition ratios.

6. The ultraviolet photo-detecting device of claim 1 , wherein the light absorption layer comprises a thickness in a range of 0.1 μm to 0.5 μm.

7. The ultraviolet photo-detecting device of claim 1 , wherein the light absorption layer comprises aluminum gallium nitride (AlGaN).

8. The ultraviolet photo-detecting device of claim 1 , wherein the light absorption layer comprises primary and secondary light absorption layers,
wherein:
the primary light absorption layer is disposed on the secondary light absorption layer; and
the secondary light absorption layer is disposed on the first nitride layer.

9. The ultraviolet photo-detecting device of claim 8 , wherein the secondary light absorption layer has a band-gap energy lower than that of the light absorption layer.

10. The ultraviolet photo-detecting device of claim 8 , wherein the secondary light absorption layer comprises a multilayer structure comprising at least one AlGaN layer.

11. The ultraviolet photo-detecting device of claim 10 , wherein the multilayer structure of the secondary light absorption layer comprises nitride layers having different composition ratios, which are alternately stacked at least 10 times.

12. The ultraviolet photo-detecting device of claim 10 , wherein the multilayer structure of the secondary light absorption layer comprises an Al x Ga 1−x N layer (0<x<1) and an Al y Ga 1−y N layer (0<y<1, y<x) disposed on the Al x Ga 1−x N layer.

13. The ultraviolet photo-detecting device of claim 10 , further comprising:
a first delta layer disposed between the primary light absorption layer and the secondary light absorption layer,
wherein the first delta layer has a Al ratio higher than an average Al ratio of the light absorption layer and an average Al ratio of the secondary light absorption layer, and
wherein the first delta layer has a thickness greater than 0 nm and less than 10 nm.

14. The ultraviolet photo-detecting device of claim 13 , wherein the secondary light absorption layer further comprises at least one second delta layer disposed between adjacent layers of the multilayer structure of the secondary light absorption layer, the at least one second delta layer having a higher Al ratio than other layers of the multilayer structure of the secondary light absorption layer.

15. The ultraviolet photo-detecting device of claim 14 , wherein the multilayer structure comprises:
an Al x Ga 1−x N layer (0<x<1); and
an Al y Ga 1−y N layer (0<y<1, y<x) disposed on the Al x Ga 1−x N layer,
wherein the at least one second delta layer is disposed between the Al x Ga 1−x N layer and the Al y Ga 1−y N layer.

16. The ultraviolet photo-detecting device of claim 15 , wherein the multilayer structure comprises alternately stacked layers of the Al x Ga 1−x N layer and the Al y Ga 1−y N layer, and
wherein the at least one second delta layer is disposed on at least one of the Al y Ga 1−y N layers and not disposed directly on the Al x Ga 1−x N layers.

17. The ultraviolet photo-detecting device of claim 13 , wherein the first delta layer has an increasing Al ratio in a direction from the first nitride layer toward the light absorption layer.

18. The ultraviolet photo-detecting device of claim 8 , wherein the secondary light absorption layer is configured to absorb light in a wavelength of 320 nm to 395 nm.

19. The ultraviolet photo-detecting device of claim 1 , wherein the light absorption layer comprises a multilayer structure.

20. The ultraviolet photo-detecting device of claim 19 , wherein the multilayer structure of the light absorption layer comprises an Al x Ga 1−x N layer (0<x<1) and an Al y Ga 1−y N layer (0<y<1, y<x) disposed on the Al x Ga 1−x N layer.

21. The ultraviolet photo-detecting device of claim 1 , further comprising:
a cap layer disposed between the light absorption layer and the Schottky junction layer,
wherein the cap layer comprises an Mg-doped nitride layer.

22. The ultraviolet photo-detecting device of claim 1 , wherein, according to a photoluminescence (PL) properties measurement of the ultraviolet photo-detecting device, a first peak light intensity is greater than a second peak light intensity, and
wherein the first peak light intensity is a peak light intensity of light emitted from the light absorption layer, and the second peak light intensity is a peak light intensity of light emitted from the second nitride layer.

23. The ultraviolet photo-detecting device of claim 22 , wherein the second peak light intensity is 50% or less than that of the first peak light intensity.

24. An ultraviolet (UV) photo-detecting device, comprising:
a substrate;
a first nitride layer disposed on the substrate;
a second nitride layer disposed between the first nitride layer and the substrate;
a secondary light absorption layer disposed on the first nitride layer;
a primary light absorption layer disposed on the secondary light absorption layer; and
a Schottky junction layer disposed on the primary light absorption layer,
wherein the secondary light absorption layer comprises a nitride layer having lower band-gap energy than the primary light absorption layer.

Assignees

• Seoul Viosys Co Ltd

Inventors

• Park Ki Yon
• Kim Hwa Mok
• Lee Kyu Ho
• Lee Sung Hyun
• Kim Hyung Kyu

Classifications

• H01L31/108

  Electricity · mapped topic

• H01L31/1856

  Electricity · mapped topic

• H01L31/1848

  Electricity · mapped topic

• H01L31/03048

  Electricity · mapped topic

• Y02E10/544

  Solar cells from Group III-V materials · CPC title