Sensor chip and electronic device
An imaging device comprises a sensor substrate including a pixel array that includes at least a first pixel. The first pixel includes an avalanche photodiode including a light receiving region, a cathode, and an anode. The first pixel includes a wiring layer electrically connected to the cathode and arranged in the sensor substrate such that the wiring layer is in a path of incident light that exits the light receiving region.
1. A light detecting device, comprising:
a sensor substrate including a pixel array that includes at least a first pixel, the first pixel including:
an avalanche photodiode including a light receiving region, a cathode, and an anode;
a first wiring electrically connected to the cathode and arranged in the sensor substrate such that the first wiring is in a path of incident light that exits the light receiving region;
a second wiring electrically connected to the anode;
a first conductive pad electrically connected to the first wiring; and
a second conductive pad electrically connected to the second wiring; and
a logic substrate including a third conductive pad directly connected to the first conductive pad and a fourth conductive pad directly connected to the second conductive pad.
2. The light detecting device of claim 1 , wherein the sensor substrate further comprises:
an isolation section at a peripheral area of the first pixel to isolate the first pixel from at least a second pixel that is adjacent to the first pixel.
3. The light detecting device of claim 2 , wherein the isolation section further comprises:
an insulating material that electrically isolates the first pixel from the second pixel; and
a reflective material that reflects light incident to the peripheral area of the first pixel towards the light receiving area.
4. The imaging device of claim 3 , wherein the isolation section is in a trench of the sensor substrate, and wherein the insulating material surrounds the reflective material in the trench.
5. The imaging device of claim 4 , wherein the reflective material is conductive.
6. The light detecting device of claim 2 , wherein the sensor substrate includes a fifth conductive pad electrically connected to the isolation section and configured to apply a bias voltage from the logic substrate to the isolation section.
7. The light detecting device of claim 6 , wherein the sensor substrate further comprises:
a light shielding film between the first wiring and at least one of the first, second and fifth conductive pads.
8. The light detecting device of claim 7 , wherein the light shielding film includes a portion that is electrically connected to the isolation section.
9. The light detecting device of claim 2 , wherein the sensor substrate further comprises:
a lens arranged between the light receiving region and the first wiring.
10. The light detecting device of claim 2 , wherein the sensor substrate further comprises:
a reflective film between the light receiving region and the first wiring.
11. The light detecting device of claim 2 , wherein, in a plan view, the isolation section forms a grid pattern to isolate the first pixel from the second pixel and other surrounding pixels.
12. The light detecting device of claim 11 , wherein, in the plan view, the first wiring is in a central portion of the first pixel and covers the cathode.
13. The light detecting device of claim 1 , wherein the first, second, third and fourth conductive pads are disposed to overlap the first pixel along a first direction.
14. A light detecting device, comprising:
a logic substrate for processing image signals;
a sensor substrate including at least a first pixel, the first pixel including:
an avalanche photodiode that includes a light receiving region, a cathode, and an anode;
a first wiring electrically connected to the cathode and between the light receiving region and the logic substrate such that the first wiring is in a path of incident light that exits the light receiving region; and
a second wiring electrically connected to the anode; and
a bonding section that electrically connects the sensor substrate to the logic substrate,
wherein the bonding section includes a first conductive pad of the sensor substrate electrically connected to the first wiring, a second conductive pad of the sensor substrate electrically connected to the second wiring, a third conductive pad of the logic substrate directly connected to the first conductive pad and a fourth conductive pad of the logic substrate directly connected to the second conductive pad.
15. The light detecting device of claim 14 , wherein the sensor substrate further comprises:
an isolation section that isolates the first pixel from at least a second pixel that is adjacent to the first pixel.
16. The light detecting device of claim 15 , wherein the bonding section includes
a fifth conductive pad electrically connected to the isolation section.
17. The light detecting device of claim 16 , wherein the fifth conductive pad is configured to apply a bias voltage received from the logic substrate to the isolation section.
18. The light detecting device of claim 15 , wherein the sensor substrate further comprises at least one of:
a light shielding film between the first wiring and the logic substrate;
a lens between the light receiving region and the first wiring; and
a reflective film between the light receiving region and the first wiring.
19. The light detecting device of claim 14 , wherein the first, second, third and fourth conductive pads are disposed to overlap the first pixel along a first direction.
20. A light detecting device, comprising:
a sensor substrate including at least a first pixel, the first pixel including:
an avalanche photodiode that includes a light receiving region, a cathode, and an anode;
a first wiring electrically connected to the cathode; and
a second wiring electrically connected to the anode;
an isolation section that isolates the first pixel from a second pixel that is adjacent to the first pixel; and
a plurality of conductive pads that bonds the sensor substrate to a logic substrate, the plurality of conductive pads including:
a first conductive pad of the sensor substrate electrically connected to the first wiring;
a second conductive pad of the sensor substrate electrically connected to the second wiring;
a third conductive pad of the sensor substrate electrically connected to the isolation section;
a fourth conductive pad of the logic substrate directly connected to the first conductive pad; and
a fifth conductive pad of the logic substrate directly connected to the second conductive pad.