Solid-state imaging apparatus, method of manufacturing the same, and electronic device

A solid-state imaging apparatus comprising:

• a first charge accumulation region and a second charge accumulation region provided separated from each other in a semiconductor layer;
• and
• a transfer transistor in which a channel is formed in the semiconductor layer adjacent to a gate electrode with a gate insulating film interposed between the semiconductor layer and the gate electrode, and signal charges accumulated in the first charge accumulation region are transferred to the second charge accumulation region through the channel, wherein
• the gate insulating film includes an eighth portion having a first relative dielectric constant and a ninth portion having a second relative dielectric constant higher than the first relative dielectric constant, and
• the ninth portion is provided on a downstream side in a transfer direction of the signal charges in the gate insulating film.

A method of manufacturing a solid-state imaging apparatus, the method comprising:

• forming a first charge accumulation region and a second charge accumulation region in a semiconductor layer;
• forming a transfer transistor having a gate electrode and a gate insulating film and configured to transfer signal charges accumulated in the first charge accumulation region to the second charge accumulation region;
• and
• forming the gate insulating film having a thickness that is thinner on a downstream side in a transfer direction of the signal charges than a thickness of the gate insulating film on an upstream side in the transfer direction of the signal charges.

A method of manufacturing a solid-state imaging apparatus, the method comprising:

• forming a first charge accumulation region and a second charge accumulation region in a semiconductor layer;
• forming a transfer transistor having a gate electrode and a gate insulating film and configured to transfer signal charges accumulated in the first charge accumulation region to the second charge accumulation region;
• and
• forming the gate insulating film having a larger relative dielectric constant on a downstream side in a transfer direction of the signal charges than a relative dielectric constant of the gate insulating film on an upstream side in the transfer direction of the signal charges.

An electronic device comprising:

• a solid-state imaging apparatus;
• an optical lens that forms an image of image light from a subject on an imaging surface of the solid-state imaging apparatus;
• and
• a signal processing circuit that performs signal processing on a signal output from the solid-state imaging apparatus, wherein
• the solid-state imaging apparatus includes:
• a first charge accumulation region and a second charge accumulation region provided separated from each other in a semiconductor layer;
• and
• a transfer transistor in which a channel is formed in the semiconductor layer adjacent to a gate electrode with a gate insulating film interposed between the semiconductor layer and the gate electrode, and signal charges accumulated in the first charge accumulation region are transferred to the second charge accumulation region through the channel, and
• the gate insulating film of the solid-state imaging apparatus has a thickness that is thinner on a downstream side in a transfer direction of the signal charges than on an upstream side in the transfer direction of the signal charges.

An electronic device comprising:

• a solid-state imaging apparatus;
• an optical lens that forms an image of image light from a subject on an imaging surface of the solid-state imaging apparatus;
• and
• a signal processing circuit that performs signal processing on a signal output from the solid-state imaging apparatus, wherein
• the solid-state imaging apparatus includes:
• a first charge accumulation region and a second charge accumulation region provided separated from each other in a semiconductor layer;
• and
• a transfer transistor in which a channel is formed in the semiconductor layer adjacent to a gate electrode with a gate insulating film interposed between the semiconductor layer and the gate electrode, and signal charges accumulated in the first charge accumulation region are transferred to the second charge accumulation region through the channel,
• the gate insulating film includes an eighth portion having a first relative dielectric constant and a ninth portion having a second relative dielectric constant higher than the first relative dielectric constant, and
• the ninth portion is provided on a downstream side in a transfer direction of the signal charges in the gate insulating film.