PHOTOELECTRIC CONVERSION DEVICE AND METHOD OF MANUFACTURING THE SAME

• US 20100059804A1
• Filed: 09/09/2009
• Published: 03/11/2010
• Est. Priority Date: 09/10/2008
• Status: Active Grant

• Current Assignee: Trivale Technologies, LLC (Vector Capital Corporation)
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Miyayama, Takashi, HAYASHI, Masami
• Granted Patent: US 8,044,445 B2
• Time in Patent Office: Days
• US Class Current: 257/292
• CPC Class Codes: H01L 27/14603 Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
• 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 27/14663 Indirect radiation imagers, e.g. using luminescent members
• CPC Class Codes: H01L 27/14692 Thin film technologies, e.g. amorphous, poly, micro- or nanocrystalline silicon

Abstract

A photoelectric conversion device includes a thin film transistor that is placed on a substrate, a photodiode that is connected to a drain electrode of the thin film transistor and includes an upper electrode, a lower electrode and a photoelectric conversion layer placed between the upper and lower electrodes, a first interlayer insulating film that covers at least the upper electrode, a second interlayer insulating film that is placed in an upper layer of the first interlayer insulating film and covers the thin film transistor and the photodiode, and a line that is connected to the upper electrode through a contact hole disposed in the first interlayer insulating film and the second interlayer insulating film.

Claims

1. A photoelectric conversion device comprising:

a thin film transistor placed on a substrate;

a photodiode connected to a drain electrode of the thin film transistor and including an upper electrode, a lower electrode and a photoelectric conversion layer placed between the upper and lower electrodes;

a first interlayer insulating film covering at least the upper electrode;

a second interlayer insulating film placed in an upper layer of the first interlayer insulating film and covering the thin film transistor and the photodiode; and

a line connected to the upper electrode through a contact hole disposed in the first interlayer insulating film and the second interlayer insulating film.

2. The photoelectric conversion device according to claim 1, wherein the first interlayer insulating film is formed to cover the thin film transistor and the photodiode.

3. The photoelectric conversion device according to claim 1, wherein the first interlayer insulating film is formed in a size equal to a top surface of the photoelectric conversion layer or smaller than the top surface of the photoelectric conversion layer.

4. The photoelectric conversion device according to claim 1, wherein

the first interlayer insulating film is made of a silicon nitride film, and

the second interlayer insulating film is made of a film including a silicon oxide series insulating film at least on a surface in contact with the first interlayer insulating film.

5. The photoelectric conversion device according to claim 4, wherein a thickness of the first interlayer insulating film is in a range of 55 nm to 85 nm.

6. The photoelectric conversion device according to claim 4, wherein the second interlayer insulating film further includes a coating type insulating film in an upper layer than the silicon oxide series insulating film.

7. The photoelectric conversion device according to claim 1, wherein the upper electrode is placed at least on a bottom surface of the contact hole.

8. The photoelectric conversion device according to claim 7, wherein the upper electrode is made of a non-transparent conductive film and placed only on a part of the photoelectric conversion layer.

9. The photoelectric conversion device according to claim 1, further comprising:

a digital board including a low noise amplifier and an A-D converter;

a driver board driving the thin film transistor; and

a reading board reading an electric charge that is converted in the photodiode.

10. The photoelectric conversion device according to claim 9, further comprising:

a passivation film placed in an upper layer of the line; and

a scintillator placed in an upper layer than the passivation film,

wherein the photoelectric conversion device has a function of performing X-ray imaging display by converting an X-ray into visible light by the scintillator.

11. A method of manufacturing a photoelectric conversion device comprising steps of:

forming a thin film transistor on a substrate;

forming a photodiode connected to a drain electrode of the thin film transistor and including an upper electrode, a lower electrode and a photoelectric conversion layer between the upper and lower electrodes, and a first interlayer insulating film covering at least the upper electrode;

forming a second interlayer insulating film in an upper layer of the first interlayer insulating film so as to cover the thin film transistor and the photodiode; and

forming a line connected to the upper electrode through a contact hole disposed in the first interlayer insulating film and the second interlayer insulating film.

12. The method of manufacturing a photoelectric conversion device according to claim 11, wherein the step of forming the photodiode and the first interlayer insulating film comprises steps of:

forming the photodiode by depositing the lower electrode, the photoelectric conversion layer and the upper electrode and by patterning the upper electrode, the photoelectric conversion layer and the lower electrode; and

forming the first interlayer insulating film so as to cover the thin film transistor and the photodiode.

13. The method of manufacturing a photoelectric conversion device according to claim 12, wherein

the step of forming the photodiode and the first interlayer insulating film further comprises a step of performing either one or both of damage recovery processing and cleaning processing on the formed photodiode before forming the first interlayer insulating film, and

in the step of forming the photodiode, a non-transparent conductive film is formed as the upper electrode only on a part of the photoelectric conversion layer.

14. The method of manufacturing a photoelectric conversion device according to claim 11, wherein the step of forming the photodiode and the first interlayer insulating film comprises:

depositing the lower electrode, the photoelectric conversion layer and the upper electrode;

patterning the upper electrode;

depositing the first interlayer insulating film on the upper electrode, and patterning the first interlayer insulating film into a shape covering the upper electrode; and

patterning the photoelectric conversion layer and the lower electrode to form the photodiode.

15. The method of manufacturing a photoelectric conversion device according to claim 14, further comprising a step of:

performing either one or both of damage recovery processing and cleaning processing on the formed photodiode before forming the second interlayer insulating film in a state where the upper electrode is covered with the first interlayer insulating film.

16. The method of manufacturing a photoelectric conversion device according to claim 13, wherein the damage recovery processing is plasma processing using hydrogen gas.

17. The method of manufacturing a photoelectric conversion device according to claim 13, wherein the cleaning processing is wet processing or processing using remote plasma.

18. The method of manufacturing a photoelectric conversion device according to claim 15, wherein the damage recovery processing is plasma processing using hydrogen gas.

19. The method of manufacturing a photoelectric conversion device according to claim 15, wherein the cleaning processing is wet processing or processing using remote plasma.