Photodetector comprising dual cells with different thickness of interposing substrates, photodetection device, laser imaging detection and ranging apparatus and method of manufacturing a photodetector

Patent metadata

Field	Value
Publication number	US-11189746-B2
Application number	US-201815907899-A
Country	US
Kind code	B2
Filing date	Feb 28, 2018
Priority date	Sep 20, 2017
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

A photodetector includes a first cell for converting incident light into electric charges, the first cell including a first semiconductor layer, a second semiconductor layer and a first substrate interposing the first semiconductor layer with the second semiconductor layer; and a second cell for converting incident light into electric charges, the second cell including a third semiconductor layer, a fourth semiconductor layer, and a second substrate interposing the third semiconductor layer with the fourth semiconductor layer; wherein the second substrate is larger in thickness than the first substrate.

First claim

What is claimed is:

1. A photodetector comprising:
a first cell for converting incident light into electric charges, the first cell including a first semiconductor layer, a second semiconductor layer and a first substrate interposing the first semiconductor layer with the second semiconductor layer; and
a second cell for converting incident light into electric charges, the second cell including a third semiconductor layer, a fourth semiconductor layer, and a second substrate interposing the third semiconductor layer with the fourth semiconductor layer;
wherein a thickness of the second substrate is larger than that of the first substrate.

2. The photodetector of claim 1 ,
wherein the first cell detects light with a first sensitivity when the amount of incident light is larger than a predetermined light amount and the second cell detects light with a second sensitivity when the amount of incident light is smaller than the predetermined light amount.

3. The photodetector of claim 2 ,
wherein the first substrate includes a depletion layer and the second substrate includes the depletion layer and a non-depletion layer.

4. The photodetector of claim 3 , further comprising:
a visible light cut layer interposing the first substrate with the first semiconductor layer and the second substrate with the third semiconductor; and
a back-surface electrode interposing the visible light cut layer with the first substrate and the second substrate.

5. The photodetector of claim 4 ,
wherein the first substrate and the second substrate are the same.

6. The photodetector of claim 5 ,
wherein the thickness of the first substrate is 10 to 30 μm.

7. The photodetector of claim 6 ,
wherein the thickness of the second substrate is 3 μm or less.

8. The photodetector of claim 7 ,
wherein the light is near-infrared light.

9. The photodetector of claim 8 ,
wherein if light is incident from the second semiconductor side and the forth semiconductor side to the first substrate and the second substrate, a material of the back-surface electrode is aluminum, an aluminum-containing material or other metal materials combined with the aluminum or the aluminum-containing material.

10. The photodetector of claim 8 ,
wherein if light is incident from the back-surface electrode side to the first substrate and the second substrate, a material of the back-surface electrode is an indium tin oxide.

11. A photodetection device comprising,
a photodetector including a first cell converting incident light into electric charges and a second cell converting incident light into electric charges, wherein the first cell includes a first semiconductor layer a second semiconductor layer and a first substrate interposing the first semiconductor layer with the second semiconductor layer, and the second cell includes a third semiconductor layer a fourth semiconductor layer and a second substrate interposing the third semiconductor layer with the fourth semiconductor layer and the second substrate is larger in thickness than the first substrate;
a first processor calculating charges from the first cell as distance information;
a second processor calculating charges from the second cell as distance information and
a distance information selector for selecting the calculated distance information by the first processor and the second processor.

12. A LIDAR apparatus comprising:
a light source emitting light to an object; and
a first cell converting incident light reflected by the object into electric charges; and
a second cell converting incident light reflected by the object into electric charges; and
wherein the first cell includes a first semiconductor layer a second semiconductor layer and a first substrate interposing the first semiconductor layer with the second semiconductor layer and the second cell includes a third semiconductor layer a fourth semiconductor layer and a second substrate interposing the third semiconductor layer with the fourth semiconductor layer; and the second substrate is larger in thickness than the first substrate.

Assignees

• Toshiba Kk

Inventors

• Ueno Risako
• Suzuki Kazuhiro
• Nobusa Yuki
• Yoshida Jiro

Classifications

• H10F71/00

  Manufacture or treatment of devices covered by this subclass (patterning processes to connect thin photovoltaic cells in integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/33; manufacture or treatment of encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells H10F19/80; manufacture or treatment of integrated devices, or assemblies of multiple devices, comprising at least one element in which radiation controls the flow of current H10F39/00) · CPC title

• H10F30/225

  the potential barrier working in avalanche mode, e.g. avalanche photodiodes · CPC title

• H10F55/17 Primary

  wherein the radiation-sensitive semiconductor devices have potential barriers · CPC title

• G01S7/4816 Primary

  of receivers alone · CPC title

• G01S7/4868

  Controlling received signal intensity or exposure of sensor · CPC title