Patent ID: 7157754

Claim:
A solid-state imaging device, comprising: a plurality of pixel cells arranged in a matrix form on a semiconductor substrate; and a driving unit that is provided for driving the plurality of pixel cells, wherein each of the plurality of pixel cells comprises: a photodiode that converts incident light into a signal charge and stores the signal charge; at least one MOS transistor that is provided for reading out the signal charge stored in the photodiode; an element isolation portion, which is formed of a STI (Shallow Trench Isolation) that is a grooved portion of the semiconductor substrate so that the photodiode and the MOS transistor are isolated from each other; and a deep-portion isolation implantation layer that is formed under the element isolation portion for preventing a flow of a charge from the photodiode to the MOS transistor, wherein the semiconductor substrate comprises: a well of a first conductivity type: a first well of a second conductivity type that is formed above the well of the first conductivity type so as to enclose the photodiode, the element isolation portion and side faces and a bottom face of the deep-portion isolation implantation layer; and a second well of the second conductivity type that is formed between the well of the first conductivity type and the first well of the second conductivity type and has an impurity density higher than an impurity density of the first well of the second conductivity type.