Photoelectric conversion element and photoelectric conversion module

Patent metadata

Field	Value
Publication number	US-11289614-B2
Application number	US-201616064165-A
Country	US
Kind code	B2
Filing date	Dec 12, 2016
Priority date	Dec 21, 2015
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

A photoelectric conversion element includes: a plurality of pixels that are formed on a common semiconductor substrate and each of which includes an avalanche photodiode; a first line that is formed on the semiconductor substrate, is electrically connected to two or more first pixels included in the plurality of pixels, and collectively extracts output currents from the two or more first pixels; and a second line that is formed on the semiconductor substrate, is electrically connected to two or more second pixels included in the plurality of pixels, and collectively extracts output currents from the two or more second pixels. A light receiving area of each first pixel is larger than a light receiving area of each second pixel.

First claim

The invention claimed is:

1. A photoelectric conversion element comprising:
a plurality of pixels that are formed on a common semiconductor substrate and each of which includes an avalanche photodiode;
a first line that is formed on the semiconductor substrate, is electrically connected to two or more first pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more first pixels; and
a second line that is formed on the semiconductor substrate, is electrically connected to two or more second pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more second pixels,
wherein a light receiving area of each first pixel is larger than a light receiving area of each second pixel, and
wherein a resistance value of the quenching resistor of each second pixel is greater than a resistance value of the quenching resistor of each first pixel.

2. The photoelectric conversion element according to claim 1 ,
wherein the two or more second pixels are disposed in a first area, and
wherein the two or more first pixels are disposed in a second area which surrounds the first area.

3. The photoelectric conversion element according to claim 1 ,
wherein a plurality of third areas including K 1 (where K 1 is an integer equal to or greater than 2) second pixels and a plurality of fourth areas including L (where L is an integer equal to or greater than 1 and L<K 1 is satisfied) first pixels are mixed and arranged in a two-dimensional shape.

4. The photoelectric conversion element according to claim 1 ,
wherein a plurality of areas including one first pixel and K 2 (where K 2 is an integer equal to or greater than 1) second pixels are arranged in a two-dimensional shape.

5. The photoelectric conversion element according to claim 1 ,
wherein a bias voltage which is applied to the second pixels is less than a bias voltage which is applied to the first pixels.

6. A photoelectric conversion element comprising:
a plurality of pixels that are formed on a common semiconductor substrate and each of which includes an avalanche photodiode;
a first line that is formed on the semiconductor substrate, is electrically connected to two or more first pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more first pixels; and
a second line that is formed on the semiconductor substrate, is electrically connected to two or more second pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more second pixels,
wherein a resistance value of the quenching resistor of each second pixel is greater than a resistance value of the quenching resistor of each first pixel.

7. The photoelectric conversion element according to claim 6 ,
wherein a light receiving area of each first pixel and a light receiving area of each second pixel are substantially equal to each other.

8. The photoelectric conversion element according to claim 6 ,
wherein the quenching resistor of each second pixel is longer than the quenching resistor of each first pixel.

9. The photoelectric conversion element according to claim 6 ,
wherein a width in a direction intersecting an extending direction of the quenching resistor of each second pixel is smaller than a width in a direction intersecting an extending direction of the quenching resistor of each first pixel.

10. The photoelectric conversion element according to claim 6 ,
wherein a bias voltage which is applied to the second pixels is less than a bias voltage which is applied to the first pixels.

11. A photoelectric conversion element comprising:
a plurality of pixels that are formed on a common semiconductor substrate and each of which includes an avalanche photodiode that operates with a common bias voltage;
a first line that is formed on the semiconductor substrate, is electrically connected to two or more first pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more first pixels;
a second line that is formed on the semiconductor substrate, is electrically connected to two or more second pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more second pixels;
a first resistor that is connected between the first line and a fixed potential line and converts the output currents from the two or more first pixels into a first voltage signal; and
a second resistor that is connected between the second line and a fixed potential line and converts the output currents from the two or more second pixels into a second voltage signal,
wherein a resistance value of the second resistor is less than a resistance value of the first resistor, and
wherein a resistance value of the quenching resistor of each second pixel is greater than a resistance value of the quenching resistor of each first pixel.

12. A photoelectric conversion module comprising:
a photoelectric conversion element; and
a reader circuit that reads an output current from the photoelectric conversion element,
wherein the photoelectric conversion element includes
a plurality of pixels that are formed on a common semiconductor substrate and each of which includes an avalanche photodiode that operates with a common bias voltage,
a first line that is formed on the semiconductor substrate, is electrically connected to two or more first pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more first pixels, and
a second line that is formed on the semiconductor substrate, is electrically connected to two or more second pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more second pixels,

wherein the reader circuit or the photoelectric conversion element includes
a first resistor that is connected between the first line and a fixed potential line and converts the output currents from the two or more first pixels into a first voltage signal, and
a second resistor that is connected between the second line and a fixed potential line and converts the output currents from the two or more second pixels into a second voltage signal,

wherein a resistance value of the second resistor is less than a resistance value of the first resistor, and
wherein a resistance value of the quenching resistor of each second pixel is greater than a resistance value of the quenching resistor of each first pixel.

13. The photoelectric conversion module according to claim 12 ,
wherein the reader circuit includes:
a photon counting circuit that counts current pulses output from the two or more first pixels on the basis of the first voltage signal; and
an A/D converter that generates a digital signal corresponding to the second voltage signal.

14. A photoelectric conversion element comprising:
a plurality of pixels that are formed on a common semiconductor substrate and each of which includes an avalanche photodiode;
a first line that is formed on the semiconductor substrate, is electrically connected to two or more first pixels included in the plurality of pixels via a quenching resistor, and collectively extracts output currents from the two or more first pixels; and
a second line that is formed on the semiconductor substrate, is electrically connected to two or more second pixels included in the plurality of

Assignees

• Hamamatsu Photonics Kk

Inventors

• Yamamoto Koei
• Nakamura Shigeyuki
• Nagano Terumasa
• Sato Kenichi

Classifications

• H04N25/78

  Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters · CPC title

• H10F39/12

  Image sensors · CPC title

• H10F39/10

  Integrated devices · CPC title

• H10F30/225

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

• H10F30/20

  the devices having potential barriers, e.g. phototransistors · CPC title