Solid-state imaging device

1. A solid-state imaging device, comprising:

a photoelectric conversion element;

a pixel region including a modulation part formed adjacent to the photoelectric conversion element; and

a peripheral region in which a peripheral circuit including a driving circuit driving the photoelectric conversion element and the modulation part is disposed, wherein the peripheral region includes a transistor that a sidewall is formed on a side of a gate electrode; and

wherein the pixel region includes:

a transistor that no sidewall is formed on a side of a gate electrode;

a substrate of one conductivity type;

a first impurity layer of a reverse conductivity type formed on the substrate;

a second impurity layer of one conductivity type formed on the first impurity layer in a forming region of the photoelectric conversion element;

a third impurity layer of one conductivity type formed on the first impurity layer in a forming region of the transistor, photo-generated charges being transferred to the third impurity layer from the second impurity layer;

a gate electrode formed above the third impurity layer above the substrate, the gate electrode having an opening and no sidewall on a side thereof;

a source formed on a surface side of the substrate in the opening; and

a drain formed apart from the source and electrically coupled to the first impurity layer.

2. The solid-state imaging device according to claim 1 , wherein the gate electrode is formed in a ring-shape.

3. The solid-state imaging device according to claim 1 , further comprising:

a fourth impurity layer formed under the gate electrode in the third impurity layer so as to be highly doped than the third impurity layer.