Solid-state image sensor and camera utilizing light attenuating films

Patent metadata

Field	Value
Publication number	US-9305954-B2
Application number	US-201414200730-A
Country	US
Kind code	B2
Filing date	Mar 7, 2014
Priority date	Mar 11, 2013
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A sensor has first pixels each including one of red, green and blue color filters, and second pixels each including one of red, green and blue color filters. In the first and second pixels including color filters of the same color, light transmittances of the light transmissive portions are different. A light transmittance of the light transmissive portion of the first pixel including the red color filter is lower than that of the light transmissive portion of the first pixel including the green color filter, and a light transmittance of the transmissive portion of the first pixel including the green color filter is lower than that of the light transmissive portion of the first pixel including the blue color filter.

First claim

What is claimed is:

1. A solid-state image sensor comprising a plurality of first pixels each including one of a red color filter, a green color filter, and a blue color filter, and a plurality of second pixels each including one of a red color filter, a green color filter, and a blue color filter, wherein
each of the plurality of first pixels includes a first photoelectric converter, and a first light transmissive portion having a first light attenuating film and arranged above the first photoelectric converter, and each of the plurality of second pixels includes a second photoelectric converter, and a second light transmissive portion having a second light attenuating film and arranged above the second photoelectric converter,
the first and the second light attenuating films for the same color are configured such that light transmittances of the first and second light transmissive portions of the same color are different, and
the first attenuating film is further configured such that a light transmittance of the first light transmissive portion of the first pixel including the red color filter is lower than that of the first light transmissive portion of the first pixel including the green color filter, and a light transmittance of the first light transmissive portion of the first pixel including the green color filter is lower than that of the first light transmissive portion of the first pixel including the blue color filter.

2. The sensor according to claim 1 , wherein
the first pixel has a first opening formed in a light-shielding layer, and the second pixel has a second opening formed in the light-shielding layer, and
a light transmittance of the first light transmissive portion is lower than that of the second light transmissive portion, and an area of the first opening is smaller than that of the second opening.

3. The sensor according to claim 1 , wherein
the first pixel includes a first optical member above the first light transmissive portion, and the second pixel includes a second optical member above the second light transmissive portion, and
a light transmittance of the first light transmissive portion is lower than that of the second light transmissive portion, and an amount of light entering the first light transmissive portion through the first optical member is smaller than that of light entering the second light transmissive portion through the second optical member.

4. The sensor according to claim 1 , wherein the first light transmissive portions of the plurality of first pixels and the second light transmissive portions of the plurality of second pixels are arranged below a layer where the red, green and blue color filters of the plurality of first pixels and the red, green and blue color filters of the plurality of second pixels are arranged.

5. The sensor according to claim 1 , wherein the first photoelectric converters of the plurality of first pixels and the second photoelectric converters of the plurality of second pixels have the same size.

6. A solid-state image sensor, comprising a plurality of first pixels each including one of a red color filter, a green color filter, and a blue color filter, and a plurality of second pixels each including one of a red color filter, a green color filter, and a blue color filter, wherein
each of the plurality of first pixels includes a first photoelectric converter, and a first light transmissive portion arranged above the first photoelectric converter, and each of the plurality of second pixels includes a second photoelectric converter, and a second light transmissive portion arranged above the second photoelectric converter,
in the first pixel and the second pixel including color filters of the same color, light transmittances of the first light transmissive portion and the second light transmissive portion are different from each other,
a light transmittance of the first light transmissive portion of the first pixel including the red color filter is lower than that of the first light transmissive portion of the first pixel including the green color filter, and a light transmittance of the first light transmissive portion of the first pixel including the green color filter is lower than that of the first light transmissive portion of the first pixel including the blue color filter, and
the first photoelectric converter and the second photoelectric converter are formed in a semiconductor substrate, the first light transmissive portion includes a first light attenuating film, the second light transmissive portion includes a second light attenuating film, and the first light attenuating film and the second light attenuating film are made of the same material and have thicknesses different from each other.

7. The sensor according to claim 6 , wherein lower surfaces of the first light attenuating film and the second light attenuating film exist at the same height with respect to a surface of the semiconductor substrate.

8. The sensor according to claim 6 , wherein the first light transmissive portion includes a first insulating film contacting the first light attenuating film and made of a material different from that of the first light attenuating film, and the second light transmissive portion includes a second insulating film contacting the second light attenuating film and made of a material different from that of the second light attenuating film.

9. The sensor according to claim 6 , wherein the first light attenuating film and the second light attenuating film are made of polysilicon.

10. The sensor according to claim 6 , wherein each of the first light attenuating film and the second light attenuating film is formed by one of a metal film and a metal compound film whose thickness is determined such that light is transmitted.

11. A camera comprising:
a solid-state image sensor comprising a plurality of first pixels, each including one of a red color filter, a green color filter, and a blue color filter, and a plurality of second pixels, each including one of a red color filter, a green color filter, and a blue color filter; and
a processing unit configured to process an output signal from the solid-state image sensor, wherein
each of the plurality of first pixels further includes a first photoelectric converter, and a first light transmissive portion having a first light attenuating film and arranged above the first photoelectric converter and each of the sluralit of second sixels further includes a second photoelectric converter, and a second light transmissive portion having a second light attenuating film and arranged above the second photoelectric converter,
the first and second light attenuating films for the same color are configured such that light transmittances of the first and second light transmissive portions of the same color are different from each other, and
the first attenuating film is further configured such that a light transmittance of the first light transmissive portion of the first pixel including the red color filter is lower than that of the first light transmissive portion of the first pixel including the green color filter, and a light transmittance of the first light transmissive portion of the first pixel including the green color filter is lower than that of the first light transmissive portion of the first pixel including the blue color filter.

12. A solid-state image sensor comprising a plurality of first pixels each including one of a red color filter, a green color filter, and a blue color filter, and a plurality of second pixels each including one of a red color filter, a green color filter, and a blue color filter, wherein
each of the plurality of first pixels includes a

Assignees

• Canon Kk

Inventors

• Kato Satoshi
• Kobayashi Hideo
• Ogura Masanori
• Kuroda Yukihiro

Classifications

• H04N25/585

  with pixels having different sensitivities within the sensor, e.g. fast or slow pixels or pixels having different sizes · CPC title

• H04N25/134

  based on three different wavelength filter elements · CPC title

• H10F39/8057

  Optical shielding · CPC title

• H10F39/8053

  Colour filters · CPC title

• H10F39/806 Primary

  Optical elements or arrangements associated with the image sensors · CPC title