PHOTODETECTOR

• US 20150053922A1
• Filed: 05/10/2013
• Published: 02/26/2015
• Est. Priority Date: 05/16/2012
• Status: Abandoned Application

• Current Assignee: Hamamatsu Photonics KK
• Original Assignee: Hamamatsu Photonics KK
• Inventors: Nakajima, Kazutoshi, Yamanishi, Masamichi, Fujita, Kazuue, Niigaki, Minoru, Hirohata, Toru, Yamashita, Hiroyuki, Akahori, Wataru
• Application Number:
  US14/390,842
• Publication Number:
  US 20150053922A1
• Time in Patent Office: Days
• US Class Current: 257/21
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 31/02164 for shielding light, e.g. light blocking layers, cold shields for infrared detectors
• CPC Class Codes: H01L 31/02327 the optical elements being integrated or being directly associated to the device, e.g. back reflectors optical coatings H01L31/0216
• CPC Class Codes: H01L 31/035209 comprising a quantum structures
• CPC Class Codes: H01L 31/035236 Superlattices; Multiple quantum well structures
• CPC Class Codes: H01L 31/101 Devices sensitive to infrared, visible or ultraviolet radiation
• CPC Class Codes: H01L 31/1035 the devices comprising active layers formed only by AIIIBV compounds

Abstract

A photodetector 1A comprises an optical element 10, having a structure including first regions and second regions periodically arranged with respect to the first regions along a plane perpendicular to a predetermined direction, for generating an electric field component in the predetermined direction when light is incident thereon along the predetermined direction; arid a semiconductor multilayer body 4 having a quantum cascade structure, arranged on the other side opposite from one side in the predetermined direction with respect to the optical element, for producing a current according to the electric field component in the predetermined direction generated by the optical element 10; while the quantum cascade structure includes an active region 4b having a first upper quantum level and a second upper quantum level lower than the first upper quantum level, and an injector region 4c for transporting an electron excited by the active region 4b.

Claims

1. A photodetector comprising:

an optical element, having a structure including first regions and second regions periodically arranged with respect to the first regions along a plane perpendicular to a predetermined direction, for generating an electric field component in the predetermined direction when light is incident thereon along the predetermined direction; and

a semiconductor multilayer body having a quantum cascade structure, arranged on the other side opposite from one side in the predetermined direction with respect to the optical element, for producing a current according to the electric field component in the predetermined direction generated by the optical element;

wherein the quantum cascade structure includes;

an active region having a first upper quantum level and a second upper quantum level lower than the first upper quantum level; and

an injector region for transporting an electron excited by the active region.

2. A photodetector according to claim 1, wherein the semiconductor multilayer body has a plurality of quantum cascade structures stacked along the predetermined direction.

3. A photodetector according to claim 1, further comprising:

a first contact layer formed on a surface on the one side of the semiconductor multilayer body; and

a second contact layer formed on a surface on the other side of the semiconductor multilayer body.

4. A photodetector according to claim 3, further comprising:

a first electrode electrically connected to the first contact layer; and

a second electrode electrically connected to the second contact layer.

5. A photodetector according to claim 3, further comprising a substrate having the second contact layer, semiconductor multilayer body, first contact layer, and optical element stacked thereon successively from the other side.

6. A photodetector according to claim 1, wherein the first regions are constituted by a dielectric body adapted to transmit therethrough light along the predetermined direction and modulate the light.

7. A photodetector according to claim 1, wherein the first regions are constituted by a metal adapted to excite a surface plasmon with the light.

8. A photodetector according to claim 1, wherein the period of arrangement of the second regions with respect to the first regions is 0.5 to 500 μ

m.

9. A photodetector according to claim 1, wherein the light is an infrared ray.

10. A photodetector according to claim 1, wherein the optical element generates the electric field component in the predetermined direction when light is incident thereon from the one side.

11. A photodetector according to claim 1, wherein the optical element generates the electric field component in the predetermined direction when light is incident thereon through the semiconductor multilayer body from the other side.