Back-illuminated imaging device with backside electrode layer and electronic apparatus thereof
An imaging device includes a semiconductor substrate having a first surface and a second surface that are opposed to each other, a plurality of pixels, and a plurality of photoelectric converters. The plurality of pixels is in a matrix, and the plurality of photoelectric converters generates, through photoelectric conversion, an electric charge corresponding to an amount of received light for each of the pixels, a first isolation section between adjacent pixels of the pixels and electrically and optically isolates the adjacent pixels from each other, a second isolation section between adjacent photoelectric converters in the pixel of the photoelectric converters and electrically isolates the adjacent photoelectric converters from each other, and an electrode layer on side of the first surface of the semiconductor substrate to extend over adjacent photoelectric converters of the photoelectric converters.
1 . An imaging device, comprising:
a semiconductor substrate having a first surface and a second surface, wherein
the first surface of the semiconductor substrate is opposite to the second surface of the semiconductor substrate,
the semiconductor substrate includes a plurality of pixels and a plurality of photoelectric converters,
the plurality of pixels is in a matrix, and
the plurality of photoelectric converters generate, through photoelectric conversion, an electric charge corresponding to an amount of received light for each of the plurality of pixels;
a first isolation section between adjacent pixels of the plurality of pixels, wherein the first isolation section electrically and optically isolates the adjacent pixels;
a second isolation section between adjacent photoelectric converters of the plurality of photoelectric converters in a unit pixel of the plurality of pixels, wherein the second isolation section electrically isolates the adjacent photoelectric converters; and
an electrode layer on a side of the first surface of the semiconductor substrate to extend over the adjacent photoelectric converters of the plurality of photoelectric converters, wherein
the first isolation section and the second isolation section extend from the second surface toward the first surface of the semiconductor substrate,
the first isolation section penetrates through the semiconductor substrate between the first surface and the second surface, and
the electrode layer is electrically coupled to the first isolation section.
2 . The imaging device according to claim 1 , wherein the electrode layer is over an entire surface of each of the plurality of pixels.
3 . The imaging device according to claim 1 , wherein
the electrode layer includes a first electrode layer and a second electrode layer,
the first electrode layer extends over the adjacent photoelectric converters, and
the second electrode layer extends over the adjacent pixels.
4 . The imaging device according to according to claim 3 , wherein
the semiconductor substrate further includes an impurity layer that is electrically coupled to the second electrode layer on the first surface, and
a potential of the impurity layer is controlled through the second electrode layer.
5 . The imaging device according to claim 4 , wherein
the impurity layer is along a side surface of the second isolation section,
the impurity layer includes a first impurity layer and a second impurity layer,
the first impurity layer is in proximity to the first surface of the semiconductor substrate on the side surface of the second isolation section,
the second impurity layer is between the second surface of the semiconductor substrate and the first impurity layer, and
an impurity concentration of the second impurity layer is lower than an impurity concentration of the first impurity layer.
6 . The imaging device according to claim 4 , wherein
the first isolation section has a bottom surface within the semiconductor substrate,
the impurity layer includes a first impurity layer and a second impurity layer,
the first impurity layer is between the first surface of the semiconductor substrate and the bottom surface of the first isolation section,
the second impurity layer is between the second surface of the semiconductor substrate and the first impurity layer, and
an impurity concentration of the second impurity layer is lower than an impurity concentration of the first impurity layer.
7 . The imaging device according to claim 1 , wherein
the semiconductor substrate further includes a pixel section in which the plurality of pixels is in the matrix, and
the electrode layer is over an entire surface of the pixel section.
8 . The imaging device according to claim 1 , wherein
the semiconductor substrate further includes a pixel section in which the plurality of pixels is in the matrix, and
the electrode layer is for the plurality of pixels.
9 . The imaging device according to claim 1 , wherein
the semiconductor substrate further includes a pixel section in which the plurality of pixels is in the matrix, and
the electrode layer is for each of the plurality of pixels.
10 . The imaging device according to claim 1 , wherein
the semiconductor substrate further includes a pixel section in which the plurality of pixels is in the matrix, and
a potential is applied to the electrode layer in a peripheral region around the pixel section.
11 . The imaging device according to claim 1 , wherein
the second isolation section has an end surface within the semiconductor substrate, and
includes the semiconductor substrate between the end surface and the first surface.
12 . The imaging device according to claim 1 , wherein a potential is applied to the electrode layer through the electrically coupled first isolation section.
13 . The imaging device according to claim 1 , wherein the second isolation section includes an impurity diffusion layer.
14 . The imaging device according to claim 1 , wherein
a first bias is applied to the electrode layer upon accumulation of the electric charge, and
a second bias, in a direction opposite to the first bias, is applied to the electrode layer upon readout.
15 . The imaging device according to claim 1 , further comprising a multi-layer wiring layer on a side of the second surface of the semiconductor substrate.
16 . The imaging device according to claim 1 , wherein
each of the first isolation section and the second isolation section includes an electrically conductive film having a light shielding property, and
a wiring line on a side of the second surface of the semiconductor substrate is electrically coupled to the electrically conductive film provided in the first isolation section.
17 . An electronic apparatus, comprising:
an imaging device that includes:
a semiconductor substrate having a first surface and a second surface, wherein
the first surface of the semiconductor substrate is opposite to the second surface of the semiconductor substrate,
the semiconductor substrate includes a plurality of pixels and a plurality of photoelectric converters,
the plurality of pixels is in a matrix, and
the plurality of photoelectric converters generate, through photoelectric conversion, an electric charge corresponding to an amount of received light for each of the plurality of pixels;
a first isolation section between adjacent pixels of the plurality of pixels, wherein the first isolation section electrically and optically isolates the adjacent pixels;
a second isolation section between adjacent photoelectric converters of the plurality of photoelectric converters in a unit pixel of the plurality of pixels, wherein the second isolation section electrically isolates the adjacent photoelectric converters; and
an electrode layer on a side of the first surface of the semiconductor substrate to extend over the adjacent photoelectric converters of the plurality of photoelectric converters, wherein
the first isolation section and the second isolation section extend from the second surface toward the first surface of the semiconductor substrate,
the first isolation section penetrates through the semiconductor substrate between the first surface and the second surface, and
the electrode layer is electrically coupled to the first isolation section.