Solid-state imaging device and method for manufacturing solid-state imaging device, and electronic device
A solid-state imaging device includes a first-conductivity-type semiconductor well region, a plurality of pixels each of which is formed on the semiconductor well region and is composed of a photoelectric conversion portion and a pixel transistor, an element isolation region provided between the pixels and in the pixels, and an element isolation region being free from an insulation film and being provided between desired pixel transistors.
1. A light detecting device comprising:
a first unit including four photoelectric conversion elements, four transfer transistors, and a first floating diffusion region positioned at a center surrounded by the four photoelectric conversion elements;
a second unit including four photoelectric conversion elements that are different than the four photoelectric conversion elements of the first unit, four transfer transistors that are different than the four transfer transistors of the first unit, and a second floating diffusion region, wherein the second unit is disposed adjacent to the first unit in a plan view;
a third unit including a first amplification transistor comprising a first pair of n-type source/drain regions, an amplification gate electrode, and a gate insulation film interposed, a first reset transistor comprising a second pair of n-type source/drain regions, a reset gate electrode, with the gate insulation film interposed, and a first select transistor comprising a third pair of n-type source/drain regions, a selection gate electrode with the gate insulation film interposed;
a fourth unit including a second amplification transistor, a second reset transistor, and a second select transistor, wherein the fourth unit is disposed adjacent to the third unit in the plan view; and
a well contact region composed only of a p-type semiconductor region disposed between the third unit and the fourth unit in the plan view,
a first element isolation region composed of a p-type semiconductor region having a lower impurity concentration than the p-type semiconductor region of the well contact region and disposed below the well contact region,
a second element isolation region composed of a p-type semiconductor region in the first and the second units and a third element isolation region composed of a p-type semiconductor region in the third and fourth units,
wherein the first element isolation region is free from the gate insulation film and the gate insulation film is disposed on a surface of the p-type semiconductor regions of the second and third element isolation regions,
wherein the four photoelectric conversion elements of the first unit share the first amplification transistor, the first reset transistor, and the first select transistor,
wherein the four photoelectric conversion elements of the second unit share the second amplification transistor, the second reset transistor, and the second select transistor,
wherein the first unit and the third unit are disposed along a vertical direction in the plan view, and
wherein the third unit and the fourth unit are disposed along a horizontal direction in the plan view.
2. The light detecting device according to claim 1 , wherein each of the first floating diffusion region and the second floating diffusion region is an impurity diffusion region.
3. The light detecting device according to claim 1 , wherein the well contact region is disposed between the first amplification transistor and the second amplification transistor in the plan view.
4. The light detecting device according to claim 1 , further comprising:
a first wiring electrically coupled to the first floating diffusion region and a gate of the first amplification transistor.
5. The light detecting device according to claim 1 , further comprising:
a second wiring electrically coupled to the second floating diffusion region and a gate of the second amplification transistor.
6. The light detecting device according to claim 1 , wherein the first unit and the second unit are disposed along the horizontal direction in the plan view.
7. The light detecting device according to claim 6 , wherein the second unit and the fourth unit are disposed along the vertical direction in the plan view.
8. The light detecting device according to claim 1 , further comprising:
a fifth unit including four photoelectric conversion elements, four transfer transistors, and a third floating diffusion region, wherein the third unit is disposed between the first unit and the fifth unit in the plan view.
9. The light detecting device according to claim 1 , wherein the well contact region is configured to apply a voltage to a semiconductor well region.
10. The light detecting device according to claim 1 , wherein the first amplification transistor is arranged between the first reset transistor and the first select transistor in the plan view.
11. The light detecting device according to claim 1 , wherein the second amplification transistor is arranged between the second reset transistor and the second select transistor in the plan view.