Solid-state imaging device with biased light shielding film
View Patent ↗A solid-state imaging device with a structure such that an electrode for reading a signal charge is provided on one side of a light-receiving sensor portion constituting a pixel; a predetermined voltage signal V is applied to a light-shielding film formed to cover an image pickup area except the light-receiving sensor portion; a second-conductivity-type semiconductor area is formed in the center on the surface of a first-conductivity-type semiconductor area constituting a photo-electric conversion area of the light-receiving sensor portion; and areas containing a lower impurity concentration than that of the second-conductivity-type semiconductor area is formed on the surface of the first-conductivity-type semiconductor area at the end on the side of the electrode and at the opposite end on the side of a pixel-separation area.
1. A solid-state imaging device comprising:
a light-receiving sensor portion having a photoelectric conversion region, the photoelectric conversion region includes a first-conductivity-type semiconductor region and a second-conductivity-type semiconductor region;
a low impurity region containing a lower impurity concentration than that of said second-conductivity-type semiconductor region, the low impurity region being positioned on a surface of said first-conductivity-type semiconductor region;
an electrode to read a signal charge from the light-receiving sensor portion; and
a light-shielding film covering an image pickup area except said light-receiving sensor portion, the light-shielding film being subject to a voltage signal from a power source electrically connected to the light-shielding film,
wherein,
the second-conductivity-type semiconductor region is centered on a surface of the first-conductivity-type semiconductor region,
the low impurity region is located in contact with the second-conductivity-type semiconductor region.
2. The solid-state imaging device according to claim 1 , wherein either a DC bias or a clock pulse, or both of them are applied as said voltage signal.
3. The solid-state imaging device according to claim 1 , further comprising:
a charge-transfer portion for transferring said read signal charge, provided on one side of said light-receiving sensor portion,
wherein said electrode also serves as a charge-transfer electrode in said charge-transfer portion.
4. The solid-state imaging device according to claim 1 , wherein said second-conductivity-type semiconductor region of said light-receiving sensor portion is formed to be self-aligned with an opening of the light-shielding film above said light-receiving sensor portion.
5. The solid-state imaging device of claim 1 , wherein the low impurity region has one side aligned with an end of the electrode.
6. The solid-state imaging device of claim 1 , wherein the low impurity region has another side aligned with an end of the pixel separation area.