Image sensor and manufacturing method of the same
An image sensor including a substrate including a first and second surface; a pixel isolation structure penetrating the substrate, arranged in a pixel isolation trench extending from the first to second surface of the substrate, and defining a pixel region; a plurality of sub pixel regions on the pixel region; a plurality of photoelectric conversion regions on the plurality of sub pixel regions; a signal separation structure between the plurality of sub pixel regions, the signal separation structure being in a signal separation trench extending from the second surface of the substrate toward the first surface of the substrate into the substrate; and a micro lens on the second surface of the substrate, the micro lens corresponding to the pixel region, wherein the signal separation structure includes an insulating layer, and the pixel isolation structure includes a conductive layer; and a liner layer between the conductive layer and the substrate.
1 . An image sensor, comprising:
a substrate including a first surface and a second surface facing each other;
a pixel isolation structure penetrating the substrate, arranged in a pixel isolation trench extending from the first surface to the second surface of the substrate, and defining a pixel region;
a plurality of sub pixel regions on the pixel region;
a plurality of photoelectric conversion regions on the plurality of sub pixel regions;
a signal separation structure between the plurality of sub pixel regions, the signal separation structure being in a signal separation trench extending from the second surface of the substrate toward the first surface of the substrate into the substrate;
a micro lens on the second surface of the substrate, the micro lens corresponding to the pixel region; and
an element isolation pattern on the first surface of the substrate,
wherein the signal separation structure includes an insulating layer,
wherein the pixel isolation structure includes:
a conductive layer;
a capping layer adjacent to the first surface of the substrate in the pixel isolation trench; and
a liner layer between the conductive layer and the substrate,
wherein the pixel isolation structure has a first depth from the second surface of the substrate, and penetrates the element isolation pattern, and
wherein the signal separation structure has a second depth from the second surface of the substrate, the second depth being less than the first depth.
2 . The image sensor as claimed in claim 1 ,
wherein the signal separation structure does not include the conductive layer.
3 . The image sensor as claimed in claim 1 ,
wherein the signal separation structure includes a silicon oxide layer, a silicon nitride layer, an undoped polysilicon layer, or air.
4 . An image sensor, comprising:
a substrate including a first surface and a second surface;
a pixel isolation structure in a pixel isolation trench that penetrates the substrate, the pixel isolation structure defining pixel regions and, in a plan view, surrounding each of the pixel regions;
a plurality of sub pixel regions on the pixel regions;
a plurality of photoelectric conversion regions respectively on the plurality of sub pixel regions;
a signal separation structure between the plurality of sub pixel regions on the pixel regions, the signal separation structure being in the pixel isolation trench extending from the second surface of the substrate into the substrate;
a micro lens on the second surface of the substrate, the micro lens corresponding to the pixel regions; and
an element isolation pattern on the first surface of the substrate,
wherein the pixel isolation structure includes:
first pixel isolators apart from each other and extending in a first direction in parallel with the first surface of the substrate, and
second pixel isolators respectively crossing the first pixel isolators, spaced apart from each other, and extending in a second direction in parallel with the first surface of the substrate and perpendicular to the first direction,
wherein the first pixel isolators include first protrusions protruding toward respective centers of the pixel regions,
wherein the first protrusions face the second direction and are spaced apart from each other,
wherein the pixel isolation structure includes:
a conductive layer,
a capping layer adjacent to the first surface of the substrate in the pixel isolation trench, and
a liner layer between the conductive layer and the substrate,
wherein the signal separation structure includes an insulating layer,
wherein the signal separation structure is spaced apart from the pixel isolation structure,
wherein the signal separation structure has a bar shape extending in the first direction,
wherein the pixel isolation structure has a first width, and penetrates the element isolation pattern, and
wherein the signal separation structure has a second width less than the first width.
5 . The image sensor as claimed in claim 4 , wherein the signal separation structure does not include the conductive layer.
6 . The image sensor as claimed in claim 4 ,
wherein the signal separation structure includes a silicon oxide layer, a silicon nitride layer, an undoped polysilicon layer, or air.
7 . The image sensor as claimed in claim 4 ,
wherein the signal separation structure includes:
a first isolator extending in the first direction; and
a second isolator crossing the first isolator and extending in the second direction.
8 . The image sensor as claimed in claim 7 ,
wherein, in a plan view, the signal separation structure has a cross shape.
9 . The image sensor as claimed in claim 4 , wherein:
the plurality of sub pixel regions comprise a first sub pixel region, a second sub pixel region, a third sub pixel region, and a fourth sub pixel region, and
the first sub pixel region, the second sub pixel region, the third sub pixel region, and the fourth sub pixel region are arranged in two rows and two columns.
10 . The image sensor as claimed in claim 4 ,
wherein the plurality of sub pixel regions includes a first sub pixel region and a second sub pixel region.
11 . The image sensor as claimed in claim 4 ,
wherein the signal separation structure, in a plan view, overlaps portions of the plurality of sub pixel regions.
12 . The image sensor as claimed in claim 4 , wherein:
the second pixel isolators include second protrusions protruding toward the respective centers of the pixel regions, and
the second protrusions face the first direction and are spaced apart from each other.
13 . The image sensor as claimed in claim 4 , wherein:
the pixel isolation structure has a first depth from the second surface of the substrate, and
the signal separation structure has a second depth from the second surface of the substrate, the second depth being less than the first depth.
14 . The image sensor as claimed in claim 4 ,
wherein a center of the signal separation structure is, in a plan view, offset from a center of the pixel regions.
15 . The image sensor as claimed in claim 4 ,
wherein a center of the micro lens is, in a plan view, offset from the center of the pixel regions.
16 . An image sensor, comprising:
a substrate including a first surface and a second surface, the substrate including first pixel group regions and second pixel group regions, the first pixel group regions being arranged in n rows and m columns and including first pixel regions for sensing a first light, the second pixel group regions being arranged in n rows and m columns and including second pixel regions, and each of the n and the m independently being a natural number of 2 or more;
a pixel isolation structure in a pixel isolation trench penetrating the substrate, the pixel isolation structure isolating a plurality of pixel regions;
a plurality of sub pixel regions in the substrate and on each pixel region of the plurality of pixel regions;
a plurality of photoelectric conversion regions on each sub pixel region of the plurality of sub pixel regions;
a signal separation structure between the plurality of sub pixel regions, the signal separation structure being arranged in the pixel isolation trench extending from the second surface of the substrate into the substrate;
micro lenses respectively on the second surface of the substrate and on the plurality of pixel regions; and
an element isolation pattern on the first surface of the substrate,
wherein the signal separation structure includes an insulating layer,
wherein the pixel isolation structure includes protrusions protruding in a direction vertical to the pixel isolation structure toward respective centers of the plurality of pixel regions,
wherein the pixel isolation structure includes:
a conductive layer; and
a liner layer between the conductive layer and the substrate,
wherein the signal separation structure is spaced apart from the pixel isolation structure, and
wherein the pixel isolation structure penetrates the element isolation pattern.