Solid-state imaging device

A solid-state imaging device comprising:

• a plurality of photoelectric converting units aligned in a first direction;
• a plurality of charge-accumulating units, each being aligned with a corresponding photoelectric converting unit in a second direction orthogonal to the first direction, and each being configured to accumulate a charge generated in the corresponding photoelectric converting unit;
• a charge-output unit configured to obtain charges respectively transferred from the plurality of charge-accumulating units, and transfer in the first direction, to output the charges;
• and
• a plurality of transfer units, each being disposed between a corresponding charge-accumulating unit of the plurality of charge-accumulating units and the charge-output unit in the second direction, and each being configured to obtain the charge accumulated in the corresponding charge-accumulating unit and transfer the obtained charge to the charge-output unit,
• each of the photoelectric converting units including:
• a photosensitive region configured to generate the charge in accordance with light incidence;
• and
• an electric potential gradient forming unit configured to form, for the photosensitive region, an electric potential gradient increasing along the second direction, the electric potential gradient forming unit being configured to accelerate migration of the charge in the second direction in the photosensitive region, and each of the charge-accumulating units including:
• a plurality of regions, including a first region, a second region, and a third region, in which an impurity concentration is gradually changed in one way in the second direction, wherein the plurality of regions are disposed in an order of the first region, the second region, and the third region in the second direction;
• and
• an electrode, including a first electrode and a second electrode, disposed over the plurality of regions in which the impurity concentration is gradually varied, and configured to apply an electric field to the plurality of regions, wherein the first electrode is disposed over the first region and the second region, the second electrode is disposed over the second region and the third region, and wherein the second electrode is applied with a voltage higher than that applied to the first electrode.