SOLID-STATE IMAGING DEVICE AND PROCESS OF MAKING SOLID STATE IMAGING DEVICE

• US 20110049661A1
• Filed: 08/27/2010
• Published: 03/03/2011
• Est. Priority Date: 08/28/2009
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: SUZUKI, Hideyuki, SAWAKI, Daigo, GOTO, Takashi, MAEHARA, Yoshiki
• Granted Patent: US 8,232,616 B2
• Time in Patent Office: Days
• US Class Current: 257/432
• CPC Class Codes: H01L 27/14609 Pixel-elements with integrated switching, control, storage or amplification elements scanning details of imagers (circuitry of solid-state image sensors H04N25/00); circuitry of imagers H04N25/70
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 27/14629 Reflectors
• CPC Class Codes: H01L 27/14645 Colour imagers
• CPC Class Codes: H01L 27/14687 Wafer level processing
• CPC Class Codes: H01L 27/14692 Thin film technologies, e.g. amorphous, poly, micro- or nanocrystalline silicon
• CPC Class Codes: H10K 30/353 comprising blocking layers, e.g. exciton blocking layers
• CPC Class Codes: H10K 39/32 Organic image sensors
• CPC Class Codes: H10K 85/621 Aromatic anhydride or imide compounds, e.g. perylene tetra-carboxylic dianhydride or perylene tetracarboxylic di-imide
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A solid state imaging device includes an array of pixels, each of the pixels includes: a pixel electrode; an organic layer; a counter electrode; a sealing layer; a color filter; and a readout circuit as defined herein, the photoelectric layer contains an organic p type semiconductor and an organic n type semiconductor, an ionization potential of the charge blocking layer and an electron affinity of the organic n type semiconductor in the photoelectric layer have a difference of at least 1 eV, and the solid-state imaging device further includes a transparent partition wall between adjacent color filters of adjacent pixels of the array of pixels, the partition wall being made from a transparent material having a lower refractive index than a material forming the color filters.

Claims

1. A solid state imaging device comprising an array of pixels, each of the pixels comprising:

a pixel electrode;

an organic layer which is provided above the pixel electrode and comprises a photoelectric layer generating charges in response to light received;

a counter electrode which is provided above the organic layer and is common to the pixels;

a sealing layer covering the counter electrode;

a color filter provided above the sealing layer; and

a readout circuit reading a signal corresponding to the charge collected by the pixel electrode,

the photoelectric layer containing an organic p type semiconductor and an organic n type semiconductor,

the organic layer further comprising a charge blocking layer between the photoelectric layer and at least one of the pixel electrode and the counter electrode to block charge injection from the at least one of the pixel electrode and the counter electrode to the photoelectric layer,

an ionization potential of the charge blocking layer and an electron affinity of the organic n type semiconductor in the photoelectric layer having a difference of at least 1 eV, and

the solid-state imaging device further comprising a transparent partition wall between adjacent color filters of adjacent pixels of the array of pixels, the partition wall being made from a transparent material having a lower refractive index than a material forming the color filters.

2. The solid-state imaging device according to claim 1, wherein the material forming the partition wall comprises a fluororesin.

3. The solid-state imaging device according to claim 1, wherein the partition wall is made from the transparent material which has a refractive index of smaller than 1.5.

4. The solid-state imaging device according to claim 2, wherein the partition wall is made from the transparent material which has a refractive index of smaller than 1.5.

5. The solid-state imaging device according to claim 1, wherein the partition wall is made from the transparent material which has a refractive index of smaller than 1.4.

6. The solid-state imaging device according to claim 2, wherein the partition wall is made from the transparent material which has a refractive index of smaller than 1.4.

7. The solid-state imaging device according to claim 1, wherein the color filter is made from a photo-insensitive curing composition free of a photo curing component.

8. The solid-state imaging device according to claim 2, wherein the color filter is made from a photo-insensitive curing composition free of a photo curing component.

9. The solid-state imaging device according to claim 3, wherein the color filter is made from a photo-insensitive curing composition free of a photo curing component.

10. The solid-state imaging device according to claim 1, wherein the color filter is made from a thermosetting composition.

11. The solid-state imaging device according to claim 2, wherein the color filter is made from a thermosetting composition.

12. The solid-state imaging device according to claim 3, wherein the color filter is made from a thermosetting composition.

13. A method for fabricating the solid-state imaging device according to claim 1, comprising, in the following order:

forming red color filters and blue color filters in a Bayer array,

forming the partition walls,

forming green color filters, and

planarizing the red color filters, the blue color filters, the green color filters, and the partition walls by chemical mechanical polishing or etch-back.

14. The method for fabricating the solid-state imaging device according to claim 13, wherein the color filters are formed by dry etching.