Method for resetting photoelectric conversion device, and photoelectric conversion device

Patent metadata

Field	Value
Publication number	US-9197220-B2
Application number	US-201213665037-A
Country	US
Kind code	B2
Filing date	Oct 31, 2012
Priority date	Oct 31, 2011
Publication date	Nov 24, 2015
Grant date	Nov 24, 2015

Abstract

A reset method of an photoelectric conversion device at least including a phototransistor having a first collector, a first base, and a first emitter, and a first field-effect transistor having a first source, a first drain, and a first gate, includes: connecting the first base, and one of the first source and the first drain of the first field-effect transistor by having a common region, or a continuous region, without a base electrode; supplying a base reset potential to the other of the first source and the first drain; and overlapping a time in which a first emitter potential is supplied to the first emitter and a time in which a first ON-potential that turns on the first field-effect transistor is supplied to the first gate.

First claim

What is claimed is:

1. A photoelectric conversion device comprising:
a first semiconductor region of a first conductivity type;
a second semiconductor region of an opposite conductivity type opposite to the first conductivity type that is in contact with the first semiconductor region;
a third semiconductor region of the opposite conductivity type that is separate from the second semiconductor region, and is in contact with the first semiconductor region;
a fifth semiconductor region of the first conductivity type that is in contact with the second semiconductor region;
a first insulating film that is provide on at least a surface of the first semiconductor region sandwiched between at least the second and third semiconductor regions; and
a first gate that is provided on the first insulating film across the second and third semiconductor regions,

wherein the second semiconductor region, or the first semiconductor region in a vicinity of the second semiconductor region is illuminated by light, and a photocurrent flows between the second semiconductor region and the first semiconductor region, and a time in which a first emitter potential is supplied to the fifth semiconductor region overlaps with a time in which a base reset potential is supplied to the third semiconductor region and a first gate potential that induces a channel or a current path on the surface of the first semiconductor region between the second and third semiconductor regions under the first gate is supplied to the first gate.

2. The photoelectric conversion device according to claim 1 , wherein the second semiconductor region is a first base of a phototransistor, and the fifth semiconductor region is a first emitter of the phototransistor, and the base reset potential is a value in which a base-emitter reset voltage of the phototransistor is added to the first emitter potential, and the base-emitter reset voltage is a base-emitter voltage of the phototransistor when a base-collector dark current of the phototransistor flows to the base and the emitter of the phototransistor or a voltage within ±KT/q of the base-emitter voltage, and here, K denotes Boltzmann constant, T denotes an absolute temperature of the photoelectric conversion device, and q denotes elementary charge of an electron.

3. The photoelectric conversion device according to claim 1 , wherein the first emitter voltage is a reference potential that is supplied at the time of reading out.

4. The photoelectric conversion device according to claim 1 , further comprising:
a sixth semiconductor region of the opposite conductivity type that is separate from the second semiconductor region, and is in contact with the first semiconductor region; and
a seventh semiconductor region of the first conductivity type that is in contact with the sixth semiconductor region;

wherein the sixth semiconductor region is electrically connected to the fifth semiconductor region, and the first emitter potential is obtained by supplying a reference potential to the seventh semiconductor region.

5. The photoelectric conversion device according to claim 4 , further comprising:
an eighth semiconductor region of the opposite conductivity type that is separate from the second semiconductor region and the sixth semiconductor region, and is in contact with the first semiconductor region; and
a ninth semiconductor region of the first conductivity type that is in contact with the eighth semiconductor region,

wherein the eighth semiconductor region is electrically connected to the seventh semiconductor region, and the first emitter potential is obtained by supplying a reference potential to the ninth semiconductor region.

6. The photoelectric conversion device according to claim 1 , further comprising:
a 10th semiconductor region of the opposite conductivity type that is in contact with the first semiconductor region;
an 11th semiconductor region of the opposite conductivity type that is in contact with the first semiconductor region, and is separate from the 10th semiconductor region;
a second insulating film that is provided on the surface of the first semiconductor region sandwiched between at least the 10th and 11th semiconductor regions; and
a second gate that is provided so as to bridge between the 10th and 11th semiconductor regions on the second insulating film,

wherein the 10th semiconductor region is connected to the fifth semiconductor region, and a reference potential is supplied to the 11th semiconductor region, and by a second ON-potential supplied to the second gate, a channel, or a current path is formed on the surface of the first semiconductor region between the 10th and 11th semiconductor regions, and the reference potential is supplied through the channel or the current path to the 10th semiconductor region, and as a result the first emitter potential is supplied to the fifth semiconductor region.

7. A photoelectric conversion device at least comprising:
a phototransistor having a first collector, a first base, and a first emitter;
a first field-effect transistor having a first source, a first drain, and a first gate;

wherein the first base and the first source of the first field-effect transistor are connected without a base electrode by having a common region, or a continuous region, and after a base reset potential is supplied to the first drain, a first emitter potential is supplied to the first emitter, and a first ON-potential that turns on the first field-effect transistor is supplied to the first gate, and then a saturation control potential is supplied to the first gate, and a first drain potential is supplied to the first drain.

8. The photoelectric conversion device according to claim 7 , further comprising:
a second transistor having a second base, and a second emitter;

wherein the first emitter of the phototransistor is connected to the second base of the second transistor, and the first emitter potential is obtained by supplying a reference potential to the second emitter.

9. The photoelectric conversion device according to claim 8 , further comprising:
a third transistor having a third base, and a third emitter;

wherein the second emitter of the second transistor is connected to the third base of the third transistor, and the first emitter potential is obtained by supplying a reference potential to the third emitter.

10. The photoelectric conversion device according to claim 7 , further comprising:
a second field-effect transistor having a second source, a second drain, and a second gate;

wherein one of the second source and the second drain is connected to the first emitter of the phototransistor, and electronic information is output from the other of the second source and the second drain by supplying a second ON-potential to the second gate.

11. The photoelectric conversion device according to claim 8 , further comprising:
a second field-effect transistor having a second source, a second drain, and a second gate;

wherein one of the second source and the second drain is connected to the second emitter of the second transistor, and electronic information is output from the other of the second source and the second drain by supplying a second ON-potential to the second gate.

12. The photoelectric conversion device according to claim 9 , further comprising:
a second field-effect transistor having a second source, a second drain, and a second gate;

wherein one of the second source and the second drain is connected to the third emitter of the third transistor, and electronic information is output from the other of the second source and the second drain

Assignees

• Nat Inst Of Advanced Ind Scien
• Ricoh Co Ltd

Inventors

• Hayashi Yutaka
• Ota Toshitaka
• Nagamune Yasushi
• Watanabe Hirofumi
• Negoro Takaaki
• Kimino Kazunari

Classifications

• H10F39/8033

  Photosensitive area · CPC title

• H10F39/8037 Primary

  the integrated elements comprising a transistor · CPC title

• H10F39/197

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• H10F10/12

  Photovoltaic cells having only metal-insulator-semiconductor [MIS] potential barriers · CPC title

• H03L3/00 Primary

  Starting of generators · CPC title