Light-receiving element and distance measurement module

Patent metadata

Field	Value
Publication number	US-2020028017-A1
Application number	US-201916504875-A
Country	US
Kind code	A1
Filing date	Jul 8, 2019
Priority date	Jul 18, 2018
Publication date	Jan 23, 2020
Grant date	—

Abstract

A light-receiving element includes an on-chip lens; an interconnection layer; and a semiconductor layer that is disposed between the on-chip lens and the interconnection layer. The semiconductor layer includes a first voltage application unit to which a first voltage is applied, a second voltage application unit to which a second voltage different from the first voltage is applied, a first charge detection unit that is disposed at the periphery of the first voltage application unit, a second charge detection unit that is disposed at the periphery of the second voltage application unit, and a charge discharge region that is provided on an outer side of an effective pixel region. For example, the present technology is applicable to a light-receiving element that generates distance information in a ToF method, or the like.

First claim

What is claimed is:

1 . A light-receiving element comprising:
an on-chip lens; an interconnection layer; and a semiconductor layer that is disposed between the on-chip lens and the interconnection layer, wherein the semiconductor layer includes a first voltage application unit to which a first voltage is applied, a second voltage application unit to which a second voltage different from the first voltage is applied, a first charge detection unit that is disposed at a periphery of the first voltage application unit, a second charge detection unit that is disposed at the periphery of the second voltage application unit, and a charge discharge region that is provided on an outer side of an effective pixel region.

2 . The light-receiving element according to claim 1 , wherein
the interconnection layer includes at least one layer including a reflection member, and the reflection member is provided to overlap the first charge detection unit or the second charge detection unit in a plan view.

3 . The light-receiving element according to claim 1 , wherein
the interconnection layer includes at least one layer including a light-shielding member, and the light-shielding member is provided to overlap the first charge detection unit or the second charge detection unit in a plan view.

4 . The light-receiving element according to claim 1 , wherein
the charge discharge region includes an opening pixel that is driven.

5 . The light-receiving element according to claim 1 , wherein
the charge discharge region includes a light-shielding pixel that is driven.

6 . The light-receiving element according to claim 1 , wherein
the charge discharge region includes a high-concentration N-type region to which a zero or positive voltage is applied.

7 . The light-receiving element according to claim 1 , further comprising
a P-well region, which is in contact with an insulating film at the periphery of the first and second charge detection units, at a boundary portion of pixels.

8 . The light-receiving element according to claim 7 , wherein
the P-well region has an impurity concentration higher than an impurity concentration of a photoelectric conversion region.

9 . The light-receiving element according to claim 1 , further comprising
an N-type diffusion layer, to which a zero or positive voltage is applied, in a gap region between a P-well region in which a pixel transistor is formed and an insulating film at the periphery of the first and second charge detection units.

10 . The light-receiving element according to claim 9 , wherein
the N-type diffusion layer is disposed to be shared by a pixel column inside an effective pixel region.

11 . The light-receiving element according to claim 9 , wherein
the N-type diffusion layer is disposed in a pixel outside the effective pixel region.

12 . The light-receiving element according to claim 9 , wherein
the N-type diffusion layer is disposed in each pixel inside the effective pixel region.

13 . The light-receiving element according to claim 1 , wherein
the first and second voltage application units are constituted by first and second P-type semiconductor regions each formed in the semiconductor layer.

14 . The light-receiving element according to claim 1 , wherein
the first and second voltage application units are constituted by first and second transfer transistors each formed in the semiconductor layer.

15 . A distance measurement module comprising:
a light-receiving element including an on-chip lens, an interconnection layer, and a semiconductor layer that is disposed between the on-chip lens and the interconnection layer, the semiconductor layer including a first voltage application unit to which a first voltage is applied, a second voltage application unit to which a second voltage different from the first voltage is applied, a first charge detection unit that is disposed at the periphery of the first voltage application unit, a second charge detection unit that is disposed at the periphery of the second voltage application unit, and a charge discharge region that is provided on an outer side of an effective pixel region; a light source that emits irradiation light of which brightness periodically fluctuates; and a light-emission control unit that controls an irradiation timing of the irradiation light.

Assignees

• Sony Semiconductor Solutions Corp

Inventors

• Imoto Tsutomu
• Isogai Yuji
• Maruyama Takuya
• Murase Takuro
• Watanabe Ryota
• Yamazaki Takeshi

Classifications

• G01S7/4816 Primary

  of receivers alone · CPC title

• H04N25/76

  Addressed sensors, e.g. MOS or CMOS sensors · CPC title

• H04N25/70

  SSIS architectures; Circuits associated therewith · CPC title

• G01S15/08

  Systems for measuring distance only (indirect measurement G01S15/46) · CPC title

• G01S17/32

  using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated · CPC title