Solid-state imaging device and camera
View Patent ↗A solid-state imaging device includes pixels 2 arranged two-dimensionally on a semiconductor substrate 1 . In a predetermined area in each pixel is formed a light-sensitive area 3 for receiving incident light 11 , and each pixel includes a photoelectric conversion portion 4 for converting the incident light into a signal charge. In at least some of the pixels, the center of the light-sensitive area is offset from the center of the pixel when seen from directly above a principal surface of the semiconductor substrate. Each pixel further includes a light-path change member 12 a and 12 b for deflecting incident light traveling toward the center of the pixel so as to be directed toward the center of the light-sensitive area. Thus, a solid-state imaging device simultaneously realizing the miniaturization of pixels and a high image quality is provided.
1. A solid-state imaging device comprising a semiconductor substrate and a plurality of pixels arranged on the semiconductor substrate, wherein
a predetermined number of neighboring pixels share a drain region to form a cell,
each of the plurality of pixels includes:
a photoelectric conversion portion provided on the semiconductor substrate;
a gate electrode provided between the photoelectric conversion portion and the drain region on the semiconductor substrate;
a light-path change member which is provided above the photoelectric conversion portion and has a curved surface; and
a converging lens provided above the light-path change member,
in each of the plurality of pixels, a center of the photoelectric conversion portion is displaced from a center of said each of the plurality of the pixels in a direction parallel to a principal surface of the semiconductor substrate;
in the cell, displacement directions of centers of photoelectric conversion portions in the predetermined number of pixels are different from each other, and
in each of the predetermined number of pixels in the cell, the light-path change member deflects an incident light, which has been converged by the converging lens, in accordance with a displacement direction of the center of the photoelectric conversion portion.
2. The solid-state imaging device according to claim 1 , wherein,
the plurality of pixels are arranged in a matrix such that centers of the plurality of photoelectric conversion portions are positioned at regular intervals, and
centers of the plurality of photoelectric conversion portions are deviated from the regular intervals, so that a center of each of the plurality of photoelectric conversion portions is offset from a center of a corresponding pixel when seen from directly above the principal surface of the semiconductor substrate.
3. The solid-state imaging device according to claim 1 , wherein the at least one converging lens is in a periodic arrangement such that one period corresponds to a plurality of pixels.
4. The solid-state imaging device according to claim 1 , wherein,
the plurality of pixels are arranged in a matrix such that centers of the plurality of pixels are positioned at regular intervals, and
the at least one converging lens is a lenticular lens whose vertical cross section taken along a row direction of the matrix of the plurality of pixels or whose vertical cross section taken along a column direction of the matrix of the plurality of pixels is identical throughout the matrix.
5. The solid-state imaging device according to claim 1 , wherein the light-path change member is in a shape of a lens or in a shape of a prism.
6. The solid-state imaging device according to claim 1 , wherein the light-path change members are in a periodic arrangement such that one period corresponds to a plurality of pixels.
7. The solid-state imaging device according to claim 6 , wherein,
the plurality of pixels are arranged in a matrix such that centers of the plurality of pixels are positioned at regular intervals, and
a vertical cross section, taken along a row direction of the matrix of the plurality of pixels or a column direction of the matrix of the plurality of pixels, of the light-path change members is identical throughout the matrix.
8. The solid-state imaging device according to claim 7 , wherein the light-path change members are lenticular lenses or prismatic arrays.
9. The solid-state imaging device according to claim 1 , wherein the light-path change member has a shape obtained by joining a triangular prism and a convex lens together, with an inclined plane of the triangular prism and a level plane of the convex lens being adhered to each other.
10. The solid-state imaging device according to claim 1 , wherein the solid-state imaging device is an amplifying solid-state imaging device.
11. A camera including a solid-state imaging device,
the solid-state imaging device comprising a semiconductor substrate and a plurality of pixels arranged on the semiconductor substrate, wherein
a predetermined number of neighboring pixels share a drain region to form a cell,
each of the plurality of pixels includes:
a photoelectric conversion portion provided on the semiconductor substrate;
a gate electrode provided between the photoelectric conversion portion and the drain region on the semiconductor substrate;
a light-path change member which is provided above the photoelectric conversion portion and has a curved surface; and
a converging lens provided above the light-path change member,
in each of the plurality of pixels, a center of the photoelectric conversion portion is displaced from a center of said each of the plurality of the pixels in a direction parallel to a principal surface of the semiconductor substrate,
in the cell, displacement directions of centers of photoelectric conversion portions in the predetermined number of pixels are different from each other, and
in each of the predetermined number of pixels in the cell, the light-path change member deflects an incident light, which has been converged by the converging lens, in accordance with a displacement direction of the center of the photoelectric conversion portion.
12. A solid-state imaging device comprising a semiconductor substrate and a plurality of pixels arranged on the semiconductor substrate, wherein
a predetermined number of neighboring pixels share a drain region to form a cell,
each of the plurality of pixels includes:
a photoelectric conversion portion provided on the semiconductor substrate;
a gate electrode provided between the photoelectric conversion portion and the drain region on the semiconductor substrate;
a light-path change element which is provided above the photoelectric conversion portion and has a curved surface;
a converging lens provided above the light-path change element,
in each of the plurality of pixels, a center of the photoelectric conversion portion is displaced from a center of said each of the plurality of the pixels in a direction parallel to a principal surface of the semiconductor substrate,
in the cell, displacement directions of centers of photoelectric conversion portions in the predetermined number of pixels are different from each other, and
in each of the predetermined number of pixels in the cell, the light-path change element deflects an incident light, which has been converged by the converging lens, in accordance with a displacement direction of the center of the photoelectric conversion portion,
the plurality of pixels each satisfy one of a predetermined number of positional relationships between the center of the pixel and the center of the photoelectric conversion portion when seen from directly above a principal surface of the semiconductor substrate, such that the predetermined number of neighboring pixels satisfying all of the predetermined number of positional relationships constitute one unit of pixels which is the cell,
the cell thus has a structure containing the predetermined number of neighboring pixels which is identical with that of each of other cells, and
light-path change elements in the cell form one unit of light-path change member.
13. A solid-state imaging device comprising a semiconductor substrate and a plurality of pixels arranged on the semiconductor substrate, wherein
a predetermined number of neighboring pixels share a drain region to form a cell,
each of the plurality of pixels includes:
a photoelectric conversion portion provided on the semiconductor substrate;
a gate electrode provided between the photoelectric conversion portion and the drain region on the semiconductor substrate;
a light-path change element which is provided above the photoelectric conversion portion and has a curved surface; and
a converging lens provided above the light-path change element,
in each of the plurality of pixels, a center of the photoelectric conversion portion is displaced from a center of said each of the plurality of the pixels in a direction parallel to a principal surface of the semiconductor substrate,
in the cell, displacement directions of centers of photoelectric conversion portions in the predetermined number of pixels are different from each other, and
in each of the predetermined number of pixels in the cell, the light-path change element deflects an incident light, which has been converged by the converging lens, in accordance with a displacement direction of the center of the photoelectric conversion portion,
the plurality of pixels each satisfy one of a predetermined number of positional relationships between the center of the pixel and the center of the photoelectric conversion portion when seen from directly above a principal surface of the semiconductor substrate, such that the predetermined number of neighboring pixels satisfying all of the predetermined number of positional relationships constitute one unit of pixels,
the cell thus has a structure containing the predetermined number of neighboring pixels which is identical with that of each of other cells, and
light-path change elements in a predetermined number of neighboring cells form one unit of light-path change member.