Solid-state imaging device with improved light use efficiency
Provided is a solid-state imaging device capable of reducing occurrence of noise resulting from reflected light to improve light use efficiency in a case where a solid-state imaging device is constructed to have a structure in which incident light passing through a substrate is reflected toward a photoelectric conversion unit. The solid-state imaging device includes: a photoelectric conversion unit formed in an inner portion of a substrate; a condensing unit provided on a side of the substrate which incident light enters, for condensing the incident light to the photoelectric conversion unit; and a reflecting unit provided on a side of the substrate which is opposed to the condensing unit, the reflecting unit being concave to the substrate, in which the reflecting unit has a structure for substantially aligning a same magnification imaging position of the reflecting unit with a focusing position of the condensing unit.
1. A solid-state imaging device, comprising:
two dimensionally arranged pixels including a central pixel and a peripheral pixel, with each pixel comprising:
a wiring unit;
a photoelectric conversion unit formed in an inner portion of a substrate;
a condensing unit provided on a side of the substrate through which incident light enters, for condensing the incident light to the photoelectric conversion unit; and
a reflecting unit provided on a side of the substrate which is opposed to the condensing unit, the reflecting unit being concave to the substrate, wherein
the reflecting unit has a structure for substantially aligning a same magnification imaging position of the reflecting unit with a focusing position of the condensing unit,
in the peripheral pixel, the condensing unit is disposed to be shifted from a central axis of the peripheral pixel to the central pixel side so that the focusing position of the condensing unit is shifted to the central axis of the peripheral pixel,
the reflecting unit is located closer to the substrate than the wiring unit, and
the wiring unit is disposed to be shifted from the central axis of the peripheral pixel to a side opposed to the central pixel side.
2. The solid-state imaging device according to claim 1 , wherein the reflecting unit is made of metal.
3. The solid-state imaging device according to claim 1 , wherein the solid-state imaging device comprises a back illuminated solid-state imaging device, and the wiring unit is provided on the side of the substrate which is opposed to the condensing unit.
4. The solid-state imaging device according to claim 1 , wherein the same magnification imaging position and the focusing position are located on a surface of the substrate which is located on a side at which the reflecting unit is provided.
5. The solid-state imaging device according to claim 1 , wherein the wiring unit comprises a gate electrode and multiple wiring parts and, in the peripheral pixel, the gate electrode is disposed to be shifted from the central axis of the peripheral pixel to the central pixel side.
6. The solid-state imaging device according to claim 1 , further comprising a gate electrode and multiple wiring parts, wherein the wiring unit comprises multiple wiring parts and, the multiple wiring parts are made of the same material as metal used to form the reflecting unit.
7. The solid-state imaging device according to claim 1 , further comprising an antireflection layer formed between the substrate and the reflecting unit.