Light-receiving device, method of manufacturing light-receiving device, and electronic apparatus
A light-receiving device of an embodiment of the present disclosure includes a photoelectric conversion layer that includes a first compound semiconductor with a first conductivity type and absorbs a wavelength of an infrared region, a first semiconductor layer formed on the photoelectric conversion layer, and an insulation layer formed to surround the photoelectric conversion layer and the first semiconductor layer, the first semiconductor layer having a second conductivity-type region at a middle region excluding a periphery facing the photoelectric conversion layer.
1. A light-receiving device, comprising:
a photoelectric conversion layer that includes a compound semiconductor with a first conductivity-type, wherein the photoelectric conversion layer is configured to absorb a wavelength of an infrared region to generate electric charges;
a first semiconductor layer on the photoelectric conversion layer;
a first insulation layer that surrounds each of the photoelectric conversion layer and the first semiconductor layer, wherein
the first insulation layer has an opening that faces a middle region of the first semiconductor layer,
the middle region excludes a periphery of the first semiconductor layer facing the photoelectric conversion layer, and
the middle region of the first semiconductor layer includes a region of a second conductivity-type;
a contact electrode coupled to the region of the second conductivity-type;
a multilayer wiring substrate on a surface opposite to a light-entering surface of the photoelectric conversion layer, wherein the multilayer wiring substrate includes:
a support substrate;
an inter-insulation layer on the support substrate;
a readout circuit within the inter-insulation layer, wherein the readout circuit includes a pixel circuit and a wiring layer; and
a readout electrode on the pixel circuit;
a second insulation layer that is above the inter-insulation layer and below each of the first insulation layer and the contact electrode; and
a coupling layer coupled to the contact electrode, wherein
the coupling layer is on a face of the second insulating layer,
the coupling layer projects in an X-axis direction on the second insulation layer,
the projection of the coupling layer is beyond side surfaces of the opening,
the coupling layer is configured to readout the electric charges through the contact electrode, and
the readout electrode is coupled with the contact electrode through the coupling layer.
2. The light-receiving device according to claim 1 , wherein the first insulation layer surrounds side surfaces of the photoelectric conversion layer and the first semiconductor layer, and a top face of the first semiconductor layer.
3. The light-receiving device according to claim 2 , wherein a diameter of the opening is smaller than an area of the first semiconductor layer.
4. The light-receiving device according to claim 2 , wherein
the contact electrode comprises an electrically conducting film in the opening, and
the photoelectric conversion layer is electrically coupled to the readout circuit via the electrically conducting film.
5. The light-receiving device according to claim 1 , wherein
the photoelectric conversion layer includes a second semiconductor layer on a side of the light-entering surface of the photoelectric conversion layer, and
the second semiconductor layer is surrounded by the first insulation layer.
6. The light-receiving device according to claim 5 , wherein each of the photoelectric conversion layer, the first semiconductor layer, and the second semiconductor layer is configured by the compound semiconductor.
7. The light-receiving device according to claim 6 , wherein the compound semiconductor is a group III-V semiconductor.
8. The light-receiving device according to claim 5 , wherein
the photoelectric conversion layer comprises In g e (1-x) As (0<x≤1), and
each of the first semiconductor layer and the second semiconductor layer comprises InP.
9. The light-receiving device according to claim 5 , further comprising a transparent electrode on an entire surface of the second semiconductor layer.
10. The light-receiving device according to claim 1 , wherein
the first semiconductor layer and the first insulation layer are between the photoelectric conversion layer and the multilayer wiring substrate.
11. The light-receiving device according to claim 1 , wherein the first insulation layer comprises at least one of a silicon nitride (SiN x ) film or a silicon oxide (SiO x ) film.
12. An electronic apparatus, comprising:
a plurality of pixels, wherein
each of the plurality of pixels includes a photoelectric conversion layer,
the photoelectric conversion layer includes a compound semiconductor with a first conductivity-type, and
the photoelectric conversion layer is configured to absorb a wavelength of an infrared region to generate electric charges;
a first semiconductor layer on the photoelectric conversion layer;
a first insulation layer that surrounds each of the photoelectric conversion layer and the first semiconductor layer, wherein
the first insulation layer has an opening that faces a middle region of the first semiconductor layer,
the middle region excludes a periphery of the first semiconductor layer facing the photoelectric conversion layer, and
the middle region of the first semiconductor layer includes a region of a second conductivity-type;
a contact electrode coupled to the region of the second conductivity-type;
a multilayer wiring substrate on a surface opposite to a light-entering surface of the photoelectric conversion layer, wherein the multilayer wiring substrate includes:
a support substrate;
an inter-insulation layer on the support substrate;
a readout circuit within the inter-insulation layer, wherein the readout circuit includes a pixel circuit and a wiring layer; and
a readout electrode on the pixel circuit;
a second insulation layer that is above the inter-insulation layer and below each of the first insulation layer and the contact electrode; and
a coupling layer coupled to the contact electrode, wherein
the coupling layer is on a face of the second insulating layer,
the coupling layer projects in an X-axis direction on the second insulation layer,
the projection of the coupling layer is beyond side surfaces of the opening,
the coupling layer is configured to readout the electric charges through the contact electrode, and
the readout electrode is coupled with the contact electrode through the coupling layer.
13. The electronic apparatus according to claim 12 , wherein the photoelectric conversion layer is separated by the first insulation layer for each of the plurality of pixels.