Solid-state imaging device, method of manufacturing solid-state imaging device, and electronic apparatus
Provided is a solid-state imaging device including an imaging area where a plurality of unit pixels are disposed to capture a color image, wherein each of the unit pixels includes: a plurality of photoelectric conversion portions; a plurality of transfer gates, each of which is disposed in each of the photoelectric conversion portions to transfer signal charges from the photoelectric conversion portion; and a floating diffusion to which the signal charges are transferred from the plurality of the photoelectric conversion portions by the plurality of the transfer gates, wherein the plurality of the photoelectric conversion portions receive light of the same color to generate the signal charges, and wherein the signal charges transferred from the plurality of the photoelectric conversion portions to the floating diffusion are added to be output as an electrical signal.
1. A solid-state imaging device comprising:
a semiconductor substrate;
a unit pixel in the semiconductor substrate,
wherein,
the unit pixel comprises at least four sets of four photoelectric conversion elements each, the sets being arrayed in at least a 2×2 matrix and extending along a first direction and a second direction perpendicular to the first direction,
each set comprises a floating diffusion region shared by the four photoelectric conversion elements,
each set has an output structure via which output signals of the set are output,
in each set, charge signals generated by the four photoelectric conversion elements are added in the floating diffusion region,
the floating diffusion regions of sets arrayed along the second direction are connected to each other,
outputs of the output structures of the sets arrayed along the first direction are commonly connected to a respective output signal line,
the outputs of the output structures of the sets arrayed along the second direction are commonly switched, and
the output signal lines are commonly connected.
2. The solid-state imaging device of claim 1 , wherein:
in each set, the four photoelectric conversion elements are arrayed in the first direction and the second direction,
in each set, the floating diffusion region is disposed at a central position between the four photoelectric conversion portions in a direction slanted with respect to the first direction and the second direction, and
in each set, a plurality of transfer gates are disposed so as to be interposed between the plurality of the photoelectric conversion portions and the floating diffusion region in the direction slanted with respect to the first direction and the second direction.
3. The solid-state imaging device according to claim 1 , wherein, in each set, the four photoelectric conversion portions are arrayed in the unit pixel so that the same number of the photoelectric conversion portions are aligned in each of a first direction and second direction.
4. The solid-state imaging device according to claim 1 , wherein, in each set, the photoelectric conversion elements are arrayed so that an even number of the photoelectric conversion elements are aligned in each of the first direction and the second direction.
5. The solid-state imaging device according to claim 1 , wherein, in each set, the photoelectric conversion elements are arrayed so that multiples of the four photoelectric conversion element sets are aligned in each of the first direction and the second direction.
6. The solid-state imaging device according to claim 1 , wherein the unit pixel includes:
for each set, an amplification transistor with a gate electrically connected to the floating diffusion region; and
for each set, a vertical signal line which outputs a signal obtained from the signal charges transferred to the floating diffusion region,
wherein,
a plurality of the amplification transistors are disposed in the unit pixel,
a plurality of the vertical signal lines are disposed, and the plurality of the vertical signal lines are electrically connected to each other, and
the signal output from the plurality of the vertical signal lines are smoothed.
7. The solid-state imaging device according to claim 1 , comprising:
for each set, an amplification transistor with a gate electrically connected to the floating diffusion region; and
for each set, a vertical signal line which outputs a signal obtained from the signal charges transferred to the floating diffusion region,
wherein,
a plurality of the amplification transistors have sources electrically connected to the vertical signal line.
8. The solid-state imaging device according to claim 1 , wherein each unit pixel includes a plurality of microlenses each of which focuses light on a respective photoelectric conversion portion.
9. The solid-state imaging device according to claim 1 , wherein each unit pixel includes a plurality of optical waveguides each of which guides light to a respective photoelectric conversion portion.
10. The solid-state imaging device of claim 1 , wherein each set further comprises a switch to selectively couple an output signal to its respective output signal line.