US 2020/0350347 A1 · GERMANIUM-SILICON LIGHT SENSING APPARATUS

Abstract

A method for fabricating an image sensor array having a first group of photodiodes for detecting light at visible wavelengths a second group of photodiodes for detecting light at infrared or near-infrared wavelengths, the method including growing a germanium-silicon layer on a semiconductor donor wafer; defining pixels of the image sensor array on the germanium-silicon layer; defining a first interconnect layer on the germanium-silicon layer, wherein the interconnect layer includes a plurality of interconnects coupled to the first group of photodiodes and the second group of photodiodes; defining integrated circuitry for controlling the pixels of the image sensor array on a semiconductor carrier wafer; defining a second interconnect layer on the semiconductor carrier wafer, wherein the second interconnect layer includes a plurality of interconnects coupled to the integrated circuitry; and bonding the first interconnect layer with the second interconnect layer.

Claims21

Dependent claims

1-4. (canceled)

An image sensor comprising:

a first group of photodiodes, each photodiode of the first group of photodiodes comprising:
a silicon region configured to absorb photons having a wavelength within a visible wavelength range, and to generate photo-carriers from the absorbed photons within the visible wavelength range;
a first carrier-collection region configured to collect photo-carriers generated by the silicon region;
and
a first readout region coupled to a first readout circuitry, the first readout region configured to provide the photo-carriers collected by the first carrier-collection region to the first readout circuitry;
and
a second group of photodiodes different from the first group of photodiodes, each photodiode of the second group of photodiodes comprising:
a germanium region or a germanium-silicon region configured to absorb photons having a wavelength within an infrared wavelength range or a near-infrared wavelength range, and to generate photo-carriers from the absorbed photons within the infrared or near-infrared wavelength ranges;
a second carrier-collection region configured to collect photo-carriers generated by the germanium region or the germanium-silicon region;
a second readout region coupled to a second readout circuitry, the second readout region configured to provide the photo-carriers collected by the second carrier-collection region to the second readout circuitry;
a first gate coupled to a first control signal that controls a carrier transport between the second carrier-collection region and the second readout region;
a third readout region coupled to a third readout circuitry, the third readout region configured to provide the photo-carriers collected by the second carrier-collection region to the third readout circuitry;
and
a second gate coupled to a second control signal that controls a carrier transport between the second carrier-collection region and the third readout region.

11 more elements

An imaging system comprising:

a transmitter unit;
and
a receiver unit comprising an image sensor comprising:
a first group of photodiodes, each photodiode of the first group of photodiodes comprising:
a silicon region configured to absorb photons having a wavelength within a visible wavelength range, and to generate photo-carriers from the absorbed photons within the visible wavelength range;
a first carrier-collection region configured to collect photo-carriers generated by the silicon region;
and
a first readout region coupled to a first readout circuitry, the first readout region configured to provide the photo-carriers collected by the first carrier-collection region to the first readout circuitry;
and
a second group of photodiodes different from the first group of photodiodes, each photodiode of the second group of photodiodes comprising:
a germanium region or a germanium-silicon region configured to absorb photons having a wavelength within an infrared wavelength range or a near-infrared wavelength range, and to generate photo-carriers from the absorbed photons within the infrared or near-infrared wavelength ranges;
a second carrier-collection region configured to collect photo-carriers generated by the germanium region or the germanium-silicon region;
a second readout region coupled to a second readout circuitry, the second readout region configured to provide the photo-carriers collected by the second carrier-collection region to the second readout circuitry;
a first gate coupled to a first control signal that controls a carrier transport between the second carrier-collection region and the second readout region;
a third readout region coupled to a third readout circuitry, the third readout region configured to provide the photo-carriers collected by the second carrier-collection region to the third readout circuitry;
and
a second gate coupled to a second control signal that controls a carrier transport between the second carrier-collection region and the third readout region.

14 more elements

A method of operating an image sensor, the method comprising:

receiving, by a first group of photodiodes of the image sensor, photons having a wavelength within a visible wavelength range;
providing, by the first group of photodiodes and to a first readout circuitry, first photo-carriers generated by photons having the wavelength within the visible wavelength range;
receiving, by a second group of photodiodes of the image sensor and that are different from the first group of photodiodes, photons having a wavelength within an infrared wavelength range or a near-infrared wavelength range;
determining, by a control circuitry, whether second photo-carriers generated by photons having the wavelength within the infrared wavelength range or the near-infrared wavelength range are to be provided to a second readout circuitry or to a third readout circuitry;
and
based on one or more control signals issued by the control circuitry, providing, by the second group of photodiodes to either the second readout circuitry or to the third readout circuitry, the second photo-carriers;
wherein each photodiode of the first group of photodiodes comprises:
a silicon region configured to absorb the photons having the wavelength within the visible wavelength range and to generate photo-carriers from the absorbed photons within the visible wavelength range;
a first carrier-collection region configured to collect photo-carriers generated by the silicon region;
and
a first readout region coupled to the first readout circuitry, the first readout region configured to provide the first photo-carriers collected by the first carrier-collection region to the first readout circuitry, and
wherein each photodiode of the second group of photodiodes comprises:
a germanium region or a germanium-silicon region configured to absorb the photons having the wavelength within the infrared wavelength range or the near-infrared wavelength range and to generate photo-carriers from the absorbed photons within the infrared or near-infrared wavelength ranges;
a second carrier-collection region configured to collect photo-carriers generated by the germanium region or the germanium-silicon region;
a second readout region coupled to the second readout circuitry, the second readout region configured to provide the second photo-carriers collected by the second carrier-collection region to the second readout circuitry based on the one or more control signals issued by the control circuitry;
a first gate coupled to a first control signal of the control circuitry that controls a carrier transport between the second carrier-collection region and the second readout region;
a third readout region coupled to the third readout circuitry, the third readout region configured to provide the second photo-carriers collected by the second carrier-collection region to the third readout circuitry based on the one or more control signals issued by the control circuitry;
and
a second gate coupled to a second control signal of the control circuitry that controls a carrier transport between the second carrier-collection region and the third readout region.

16 more elements

Dependencies are inferred from the claim text.

Facts

Application

16/929,861Filed 15 Jul 2020

Priority

4 Aug 2015

Published

5 Nov 2020

Term ends

Not estimatedThe source records don’t support an estimate.

Classification22 codes

H10F 39/8023
Geometry or disposition of elements in pixels, e.g. address-lines or gate electrodes: disposition of the elements in pixels, e.g. smaller elements…
H10F 30/10
Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors: the…
H10F 30/223
The devices having only one potential barrier, e.g. photodiodes: the potential barrier being a PIN barrier
H10F 39/014
Manufacture or treatment of image sensors covered by group H10F39/12: of CMOS image sensors

Family

Application62/200,652Us provisional application · filed 4 Aug 2015

Application62/209,349Us provisional application · filed 25 Aug 2015

Application62/210,946Us provisional application · filed 27 Aug 2015

Application62/211,004Us provisional application · filed 28 Aug 2015

Application62/210,991Us provisional application · filed 28 Aug 2015

Application62/217,031Us provisional application · filed 11 Sep 2015

Application62/251,691Us provisional application · filed 6 Nov 2015

Application62/271,386Us provisional application · filed 28 Dec 2015

Application15/228,282Division · filed 4 Aug 2016

Application15/712,852Continuation · filed 22 Sep 2017

Application16/929,861Continuation

Application15/712,852Division

US 10,756,127 B2Related patent

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US 2017/0040362 A1Published application

US 2018/0012917 A1Published application

US 9,954,016 B2Related patent

US 2020/0350347 A1This patent

From the US filing history. Foreign family members aren’t listed.

Germanium-silicon light sensing apparatus

Life of this patent

Germanium-silicon light sensing apparatus

Life of this patent

Abstract

Claims21