Image sensor and method for manufacturing image sensor
There is provided an image sensor including: a light polarizing unit configured to transmit light in a specific light polarization direction out of incident light; a pixel configured to generate an image signal corresponding to the light transmitted through the light polarizing unit; and a signal transfer unit formed simultaneously with the light polarizing unit and configured to transfer either of the image signal and a control signal that controls generation of the image signal.
1. An image sensor, comprising:
a plurality of pixels, each pixel including:
a photoelectric conversion unit;
a light polarizing unit;
a pixel circuit; and
a plurality of signal transfer units, wherein the plurality of signal transfer units are arranged in a peripheral portion of the image sensor, and wherein at least a portion of the light polarizing unit and at least a portion of the plurality of signal transfer units are at a same layer of the image sensor.
2. The image sensor of claim 1 , wherein the light polarizing unit includes a plurality of light blocking lines having a pitch narrower than a wavelength included in incident light.
3. The image sensor of claim 2 , further comprising:
a semiconductor substrate, wherein the photoelectric conversion unit is formed in the semiconductor substrate; and
a first flattening film, wherein the plurality of light blocking lines and the plurality of signal transfer units are formed on the first flattening film.
4. The image sensor of claim 3 , wherein the plurality of light blocking lines are arranged at equal intervals, and wherein areas between adjacent light blocking lines within a pixel are filled with air.
5. The image sensor of claim 4 , further comprising:
a protection film on a light incident side of the plurality of light blocking lines, wherein the protection film seals the areas between adjacent light blocking lines.
6. The image sensor of claim 2 , wherein the plurality of light blocking lines and the plurality of signal transfer units are formed from aluminum.
7. The image sensor of claim 3 , further comprising:
an interconnection layer on a side of the semiconductor substrate opposite a light incident side;
a plurality of via plugs; and
an interconnection included as part of each of the plurality of signal transfer units, wherein the interconnection layer is connected to each of the plurality of signal transfer units by a respective via plug and a respective interconnection, and wherein the image sensor is a back-side illumination image sensor.
8. The image sensor of claim 3 , further comprising:
an interconnection layer between a light incident side of the semiconductor substrate and the plurality of light polarizing units of each pixel, wherein the image sensor is a front-side illumination image sensor.
9. The image sensor of claim 2 , wherein the plurality of light blocking lines are formed from a plurality of layers of material, and wherein a first one of the plurality of layers of material of the plurality of light blocking lines also forms the at least the portion of the plurality of signal transfer units.
10. The image sensor of claim 9 , wherein the first one of the plurality of layers of material is a light reflecting layer, wherein a second one of the plurality of layers of material is an insulating layer, and wherein a third one of the plurality of layers of material is a light absorbing layer.
11. The image sensor of claim 2 , wherein a first pixel of the plurality of pixels includes a first light polarizing unit with first light blocking lines arranged in a first direction, and wherein a second pixel of the plurality of pixels includes a second light polarizing unit with second light blocking lines arranged in a second direction.
12. The image sensor of claim 11 , wherein the first direction is shifted by 45 degrees compared to the second direction.
13. The image sensor of claim 2 , wherein the plurality of pixels are arranged in groups of four pixels, wherein each pixel in a selected group has light blocking lines arranged in a different direction.
14. The image sensor of claim 13 , further comprising:
a plurality of color filters, wherein each pixel in the selected group includes a color filter that transmits light of a same color.
15. An image sensor, comprising:
a substrate;
a photoelectric conversion unit formed in the substrate;
a light polarizing unit on a light incident side of the substrate; and
a signal transfer unit on the light incident side of the substrate, wherein the signal transfer unit is arranged in a peripheral portion of the image sensor, and wherein the light polarizing unit and the photoelectric conversion unit are formed at a same layer of the image sensor.