Patent ID: 7358105

Claim:
A method for manufacturing a solid-state imaging device comprising a plurality of pixel cells arranged in a matrix form on a semiconductor substrate; wherein each of the plurality of pixel cells comprises: a photodiode; at least one MOS transistor that is provided for reading out the signal charge stored in the photodiode; a trench isolation portion that isolates the photodiode and the MOS transistor from each other; and a deep-portion isolation implantation layer that is formed under the trench isolation portion, and wherein the semiconductor substrate comprises: a n-type substrate; a first p-type well that is formed so as to enclose the photodiode, the trench isolation portion and side faces and a bottom face of the deep-portion isolation implantation layer; and a second p-type well that is formed between the n-type substrate and the first p-type well and has an impurity density higher than an impurity density of the first p-type well, the method comprising the steps of: grooving the semiconductor substrate so as to form a groove for the formation of the trench isolation portion; implanting an impurity from a bottom of the groove so as to form the deep-portion isolation implantation layer so that a side face and a bottom face thereof are enclosed within the first p-type well; forming the trench isolation portion in the groove after the impurity implantation step; and forming the photodiode and the at least one MOS transistor after the trench isolation portion formation step.