Photodetector and display device

• US 8,625,058 B2
• Filed: 08/23/2010
• Issued: 01/07/2014
• Est. Priority Date: 08/24/2009
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Kozuma, Munehiro, Kurokawa, Yoshiyuki, Ikeda, Takayuki, Tamura, Hikaru
• Primary Examiner(s): Connelly, Michelle R
• Application Number:
  US12/861,476
• Publication Number:
  US 20110043735A1
• Time in Patent Office: 1,233 Days
• Field of Search: 257/294
• US Class Current: 349/106
• CPC Class Codes: G01J 1/02 Details
• CPC Class Codes: G01J 1/0209 Monolithic
• CPC Class Codes: G01J 1/0214 Constructional arrangements for removing stray light
• CPC Class Codes: G01J 1/04 Optical or mechanical part supplementary adjustable parts
• CPC Class Codes: G01J 1/0411 using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
• CPC Class Codes: G01J 1/0488 with spectral filtering
• CPC Class Codes: G01J 3/506 measuring the colour produced by screens, monitors, displays or CRTs
• CPC Class Codes: G01J 3/51 using colour filters
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/65 OLEDs integrated with inorganic image sensors

Abstract

The amount of light incident on a photoelectric conversion element is increased while stray light from a backlight below a light-transmitting substrate is prevented from being incident on the photoelectric conversion element. A light-blocking film is formed with a color filter covering a photoelectric conversion element over a light-transmitting substrate and a color filter covering a photoelectric conversion element in an adjacent pixel which overlap each other at the side with respect to the direction in which light travels. In addition, by providing a microlens over the color filter, light which is conventionally not detected is collected to a photoelectric conversion element, and accordingly the amount of light incident on the photoelectric conversion element is increased.

Claims

1. A photodetector comprising:

a first photodiode over a substrate;

a second photodiode over the substrate

a first color filter covering the first photodiode;

a second color filter covering the second photodiode;

a first microlens over the first color filter;

a second microlens over the second color filter; and

a first light-blocking layer comprising a part of the first color filter and a part of the second color filter between the first photodiode and the second photodiode.

2. The photodetector according to claim 1, wherein the part of the second color filter overlaps with the part of the first color filter in a direction from the first photodiode to the second photodiode.

3. The photodetector according to claim 1, wherein the substrate is a light-transmitting substrate.

4. The photodetector according to claim 3, further comprising a second light-blocking layer over the light-transmitting substrate and a third light-blocking layer over the light-transmitting substrate,

wherein the first photodiode is provided over the second light-blocking layer with a light-transmitting insulating film interposed therebetween, and

wherein the second photodiode is provided over the third light-blocking layer with the light-transmitting insulating film interposed therebetween.

5. The photodetector according to claim 4, wherein the part of the first color filter and the part of the second color filter are in contact with the light-transmitting insulating film.

6. A photodetector comprising:

a first photodiode over a substrate;

a second photodiode over the substrate;

a first microlens over the first photodiode;

a second microlens over the second photodiode;

a first color filter covering the first microlens;

a second color filter covering the second microlens; and

a first light-blocking layer comprising a part of the first color filter and a part of the second color filter between the first photodiode and the second photodiode.

7. The photodetector according to claim 6, wherein the part of the second color filter overlaps with the part of the first color filter in a direction from the first photodiode to the second photodiode.

8. The photodetector according to claim 6, wherein the substrate is a light-transmitting substrate.

9. The photodetector according to claim 8, further comprising a second light-blocking layer over the light-transmitting substrate and a third light-blocking layer over the light-transmitting substrate,

wherein the first photodiode is provided over the second light-blocking layer with a light-transmitting insulating film interposed therebetween, and

wherein the second photodiode is provided over the third light-blocking layer with the light-transmitting insulating film interposed therebetween.

10. The photodetector according to claim 9, wherein the part of the first color filter and the part of the second color filter are in contact with the light-transmitting insulating film.

11. A photodetector comprising:

a first photodiode over a substrate;

a second photodiode over the substrate;

a first light-transmitting insulating layer covering the first photodiode;

a second light-transmitting insulating layer covering the second photodiode;

a first color filter over the first photodiode with the first light-transmitting insulating layer interposed therebetween;

a second color filter over the second photodiode with the second light-transmitting insulating layer interposed therebetween;

a first microlens over the first color filter;

a second microlens over the second color filter;

a first light-blocking layer provided in a groove which is provided between the first light-transmitting insulating layer and the second light-transmitting insulating layer;

a second light-blocking layer over the substrate; and

a third light-blocking layer over the substrate;

wherein the first photodiode overlaps with the second light-blocking layer;

wherein the second photodiode overlaps with the third light-blocking layer;

wherein the second light-blocking layer is between the first photodiode and the substrate; and

wherein the third light-blocking layer is between the second photodiode and the substrate.

12. The photodetector according to claim 11, wherein the first light-blocking layer comprises a part of the first color filter and a part of the second color filter.

13. The photodetector according to claim 12, wherein the part of the second color filter overlaps with the part of the first color filter in a direction from the first photodiode to the second photodiode.

14. The photodetector according to claim 11, wherein the substrate is a light-transmitting substrate.

15. A display device comprising:

a backlight;

a first light-transmitting substrate over the backlight;

a liquid crystal layer over the first light-transmitting substrate;

a second light-transmitting substrate over the liquid crystal layer;

a first photodiode over the first light-transmitting substrate;

a second photodiode over the first light-transmitting substrate;

a first color filter covering the first photodiode;

a second color filter covering the second photodiode;

a first microlens over the first color filter;

a second microlens over the second color filter; and

a first light-blocking layer comprising a part of the first color filter and a part of the second color filter between the first photodiode and the second photodiode.

16. The display device according to claim 15, wherein the part of the second color filter overlaps with the part of the first color filter in a direction from the first photodiode to the second photodiode.

17. The display device according to claim 15, further comprising a second light-blocking layer over the first light-transmitting substrate and a third light-blocking layer over the first light-transmitting substrate,

wherein the first photodiode is provided over the second light-blocking layer with a light-transmitting insulating film interposed therebetween, and

wherein the second photodiode is provided over the third light-blocking layer with the light-transmitting insulating film interposed therebetween.

18. The display device according to claim 17, wherein the part of the first color filter and the part of the second color filter are in contact with the light-transmitting insulating film.

19. A display device comprising:

a substrate;

a light-emitting layer over the substrate;

a light-transmitting substrate over the light-emitting layer;

a first photodiode over the substrate;

a second photodiode over the substrate;

a first color filter covering the first photodiode;

a second color filter covering the second photodiode;

a first microlens over the first color filter;

a second microlens over the second color filter; and

a first light-blocking layer comprising a part of the first color filter and a part of the second color filter between the first photodiode and the second photodiode.

20. The display device according to claim 19, wherein the part of the second color filter overlaps with the part of the first color filter in a direction from the first photodiode to the second photodiode.

21. The display device according to claim 19, wherein the substrate is a light-transmitting substrate.

22. The display device according to claim 21, further comprising a second light-blocking layer and a third light-blocking layer over the substrate,

wherein the first photodiode is provided over the second light-blocking layer with a light-transmitting insulating film interposed therebetween, and

wherein the second photodiode is provided over the third light-blocking layer with the light-transmitting insulating film interposed therebetween.

23. The display device according to claim 22, wherein the part of the first color filter and the part of the second color filter are in contact with the light-transmitting insulating film.