Photo detector, photo detection device, and lidar device

Patent metadata

Field	Value
Publication number	US-2017330982-A1
Application number	US-201715451531-A
Country	US
Kind code	A1
Filing date	Mar 7, 2017
Priority date	May 11, 2016
Publication date	Nov 16, 2017
Grant date	—

Abstract

In one embodiment, a photo detector is provided with a semiconductor layer having a light receiving surface, a first reflective material which is provided on a side opposite to the light receiving surface side of the semiconductor layer and reflects a light incident from the light receiving surface, and a slope portion provided on a side surface of the semiconductor layer.

First claim

What is claimed is:

1 . A photo detector, comprising:
a semiconductor layer having a light receiving surface; a first reflective material which is provided on a side opposite to the light receiving surface side of the semiconductor layer and reflects a light incident from the light receiving surface; and a slope portion provided on a side surface of the semiconductor layer.

2 . The photo detector according to claim 1 , further comprising:
a substrate to transmit the light on the light receiving surface of the semiconductor layer.

3 . The photo detector according to claim 1 , wherein:
an angle of a slope surface of the slope portion to a direction from the first reflective material toward the light receiving surface is not less than 10 degrees and not more than 80 degrees.

4 . The photo detector according to claim 1 , wherein:
an angle of a slope surface of the slope portion to direction from the first reflective material toward the light receiving surface is not less than 45 degrees and not more than 75 degrees.

5 . The photo detector according to claim 1 , further comprising:
a second reflective material which covers a surface of the slope portion and reflects the light incident from the light receiving surface.

6 . The photo detector according to claim 1 , wherein:
the semiconductor layer has a concave-convex portion on a surface thereof at the first reflective material side.

7 . The photo detector according to claim 1 , wherein:
the slope portion is a part of the semiconductor layer.

8 . The photo detector according to claim 1 , further comprising:
a substrate at a side of the first reflective material of the semiconductor layer.

9 . The photo detector according to claim 1 , wherein:
an angle of a slope surface of the slope portion of the semiconductor layer to a direction from the light receiving surface toward the first reflective material is not less than 10 degrees and not more than 80 degrees.

10 . The photo detector according to claim 2 , wherein:
a slope surface of the slope portion is an arc surface formed of an arc shape.

11 . A photo detector, comprising:
a semiconductor layer having a light receiving surface; a substrate provided at a side opposite to the light receiving surface side of the semiconductor layer; a first reflective material which is provided between the semiconductor layer and the substrate, and reflects a light incident from the light receiving surface; and a slope portion which is provided next to the semiconductor layer, and has a slope surface to reflect a light toward a side surface of the semiconductor layer.

12 . The photo detector according to claim 11 , wherein:
an angle of the slope surface of the slope portion to the side surface of the semiconductor layer, in a direction from the first reflective material toward the light receiving surface is not less than 10 degrees and not more than 80 degrees.

13 . The photo detector according to claim 11 , wherein:
the slope surface of the slope portion is an arc surface formed of an arc shape.

14 . The photo detector according to claim 11 , wherein:
the semiconductor layer includes a p type semiconductor layer and an n type semiconductor layer in this order in a direction from the light receiving surface toward the first reflective material.

15 . The photo detector according to claim 14 , wherein:
the semiconductor layer includes a p + type semiconductor layer, a p − type semiconductor layer, a p + type semiconductor layer, and the n type semiconductor layer in this order, in the direction from the light receiving surface toward the first reflective material.

16 . The photo detector according to claim 11 , wherein:
the semiconductor layer includes an n type semiconductor layer, and a p type semiconductor layer in this order, in a direction from the light receiving surface toward the first reflective material.

17 . The photo detector according to claim 16 , wherein:
the semiconductor layer includes an n + type semiconductor layer, an n − type semiconductor layer, an n + type semiconductor layer, and the p type semiconductor layer in this order, in the direction from the light receiving surface toward the first reflective material.

18 . The photo detector according to claim 11 , wherein:
a length of the semiconductor layer in a direction from the light receiving surface toward the first reflective material is not less than 1 μm and not more than 15 μm.

19 . A photo detection device, comprising:
a plurality of the arranged photo detectors according to claim 11 .

20 . A LIDAR device, comprising:
a light source to irradiate an object with light; the photo detection device according to claim 19 which detects the light reflected by the object; and a measuring unit to measure a distance between the object and the photo detection device.

Assignees

• Toshiba Kk

Inventors

• Yonehara Toshiya
• Suzuki Kazuhiro
• Hasegawa Rei

Classifications

• H01L31/028

  Electricity · mapped topic

• H01L27/1446

  Electricity · mapped topic

• H01L31/02327 Primary

  Electricity · mapped topic

• G01S7/4816

  of receivers alone · CPC title

• H01L31/107

  Electricity · mapped topic