Manufacturing methods of semiconductor device and light-emitting display device

• US 8,603,841 B2
• Filed: 08/24/2011
• Issued: 12/10/2013
• Est. Priority Date: 08/27/2010
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei
• Primary Examiner(s): Coleman, William D
• Assistant Examiner(s): ENAD, CHRISTINE A
• Application Number:
  US13/216,493
• Publication Number:
  US 20120052606A1
• Time in Patent Office: 839 Days
• Field of Search: 438/23, 438/104, 257/E33.019, 257/E21.698, 257/E21.002
• US Class Current: 438/23
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/1288 employing particular masking sequences or specially adapted masks, e.g. half-tone mask
• CPC Class Codes: H01L 29/41733 for thin film transistors with insulated gate

Abstract

An object is to simplify a manufacturing process of a transistor, and to manufacture a light-emitting display device not only with a smaller number of photomasks compared to the number of photomasks used in the conventional method but also without an additional step. By using an intrinsic or substantially intrinsic high-resistance oxide semiconductor for a semiconductor layer included in the transistor, so that a step of processing the semiconductor layer into an island shape in each transistor can be omitted. Unnecessary portions of the semiconductor layer are etched away at the same time as a step of forming an opening in an insulating layer formed in an upper layer of the semiconductor layer, so that the number of photolithography steps is reduced.

Claims

1. A method for manufacturing a semiconductor device comprising the steps of:

forming a first conductive film over a substrate;

forming a first resist mask over the first conductive film;

forming a first gate electrode and a second gate electrode by selectively etching the first conductive film with the use of the first resist mask;

forming a first insulating film over the first gate electrode and the second gate electrode;

forming a semiconductor film over the first insulating film;

forming a second resist mask over the semiconductor film;

forming a first opening by selectively etching part of the semiconductor film and the first insulating film over the second gate electrode with the use of the second resist mask;

forming a second conductive film so as to cover the semiconductor film and the first opening;

forming a third resist mask over the second conductive film;

forming a first source electrode, a first drain electrode, a second source electrode and a second drain electrode by selectively etching the second conductive film with the use of the third resist mask,

wherein a first transistor comprises the first gate electrode, the first source electrode and the first drain electrode,

wherein a second transistor comprises the second gate electrode, the second source electrode and the second drain electrode,

wherein one of the first source electrode and the first drain electrode is electrically connected to a source or drain wiring,

wherein the other of the first source electrode and the first drain electrode is electrically connected to the second gate electrode, and

wherein one of the second source electrode and the second drain electrode is electrically connected to a power source wiring;

forming a second insulating film over the first source electrode and the first drain electrode, the second source electrode and the second drain electrode, and the semiconductor film;

forming a fourth resist mask over the second insulating film;

forming a second opening by selectively etching the second insulating film and the semiconductor film with the use of the fourth resist mask and simultaneously forming a third opening in the second insulating film so as to expose part of the other of the second source electrode and the second drain electrode;

forming a third conductive film over the second insulating film so as to cover the third opening;

forming a fifth resist mask over the third conductive film; and

forming a pixel electrode by selectively etching the third conductive film with the use of the fifth resist mask.

2. The method for manufacturing a semiconductor device according to claim 1 further comprising the steps of:

forming a third insulating film so as to cover the second opening, the third opening, and a periphery of the pixel electrode; and

forming a layer including a light-emitting element over the pixel electrode.

3. The method for manufacturing a semiconductor device according to claim 1, wherein the semiconductor film is an oxide semiconductor.

4. The method for manufacturing a semiconductor device according to claim 1, wherein the first conductive film and the second conductive film are formed using a material containing aluminum.

5. The method for manufacturing a semiconductor device according to claim 4, wherein a maximum temperature of a heat treatment after the first conductive film or the second conductive film is formed is 380°

C. or lower.

6. The method for manufacturing a semiconductor device according to claim 1, wherein the first conductive film and the second conductive film are formed using a material containing copper.

7. The method for manufacturing a semiconductor device according to claim 6, wherein a maximum temperature of a heat treatment after the first conductive film or the second conductive film is formed is 450°

C. or lower.

8. A method for manufacturing a semiconductor device comprising the steps of:

forming a first conductive film over a substrate;

forming a first resist mask over the first conductive film;

forming a first gate electrode and a second gate electrode by selectively etching the first conductive film with the use of the first resist mask;

forming a first insulating film over the first gate electrode and the second gate electrode;

forming a semiconductor film over the first insulating film;

forming a second resist mask over the semiconductor film;

forming a first opening by selectively etching part of the semiconductor film and the first insulating film over the second gate electrode with the use of the second resist mask;

forming a second conductive film so as to cover the semiconductor film and the first opening;

forming a third resist mask over the second conductive film;

forming a first source electrode, a first drain electrode, a second source electrode and a second drain electrode by selectively etching the second conductive film with the use of the third resist mask,

wherein a first transistor comprises the first gate electrode, the first source electrode and the first drain electrode,

wherein a second transistor comprises the second gate electrode, the second source electrode and the second drain electrode,

wherein one of the first source electrode and the first drain electrode is electrically connected to a source or drain wiring,

wherein the other of the first source electrode and the first drain electrode is electrically connected to the second gate electrode,

wherein one of the second source electrode and the second drain electrode is electrically connected to a power source wiring, and

wherein a capacitor comprises a first electrode having the same material as the second gate electrode and a second electrode having the same material as the power source wiring with the first insulating film and the semiconductor film therebetween;

forming a second insulating film over the first source electrode and the first drain electrode, the second source electrode and the second drain electrode, and the semiconductor film;

forming a fourth resist mask over the second insulating film;

forming a second opening by selectively etching the second insulating film and the semiconductor film with the use of the fourth resist mask and simultaneously forming a third opening in the second insulating film so as to expose part of the other of the second source electrode and the second drain electrode;

forming a third conductive film over the second insulating film so as to cover the third opening;

forming a fifth resist mask over the third conductive film; and

forming a pixel electrode by selectively etching the third conductive film with the use of the fifth resist mask.

9. The method for manufacturing a semiconductor device according to claim 8 further comprising the steps of:

forming a third insulating film so as to cover the second opening, the third opening, and a periphery of the pixel electrode; and

forming a layer including a light-emitting element over the pixel electrode.

10. The method for manufacturing a semiconductor device according to claim 8, wherein the semiconductor film is an oxide semiconductor.

11. The method for manufacturing a semiconductor device according to claim 8, wherein the first conductive film and the second conductive film are formed using a material containing aluminum.

12. The method for manufacturing a semiconductor device according to claim 11, wherein a maximum temperature of a heat treatment after the first conductive film or the second conductive film is formed is 380°

C. or lower.

13. The method for manufacturing a semiconductor device according to claim 8, wherein the first conductive film and the second conductive film are formed using a material containing copper.

14. The method for manufacturing a semiconductor device according to claim 13, wherein a maximum temperature of a heat treatment after the first conductive film or the second conductive film is formed is 450°

C. or lower.

15. A method for manufacturing a semiconductor device comprising the steps of:

forming a first conductive film over a substrate;

forming a first resist mask over the first conductive film;

forming a first gate electrode and a second gate electrode by selectively etching the first conductive film with the use of the first resist mask;

forming a first insulating film over the first gate electrode and the second gate electrode;

forming a semiconductor film over the first insulating film;

forming a second resist mask over the semiconductor film;

forming a first opening by selectively etching part of the semiconductor film and the first insulating film over the second gate electrode with the use of the second resist mask;

forming a second conductive film so as to cover the semiconductor film and the first opening;

forming a third resist mask over the second conductive film;

forming a first source electrode, a first drain electrode, a second source electrode and a second drain electrode by selectively etching the second conductive film with the use of the third resist mask,

wherein a first transistor comprises the first gate electrode, the first source electrode and the first drain electrode,

wherein a second transistor comprises the second gate electrode, the second source electrode and the second drain electrode,

wherein one of the first source electrode and the first drain electrode is electrically connected to a source or drain wiring,

wherein the other of the first source electrode and the first drain electrode is electrically connected to the second gate electrode, and

wherein one of the second source electrode and the second drain electrode is electrically connected to a power source wiring;

forming a second insulating film over the first source electrode and drain electrode, the second source electrode and drain electrode, and the semiconductor film;

forming a third insulating film as a planarizing insulating film over the second insulating film;

forming a fourth resist mask over the third insulating film;

forming a second opening by selectively etching the third insulating film, the second insulating film, and the semiconductor film with the use of the fourth resist mask and simultaneously forming a third opening in the third insulating film and the second insulating film so as to expose part of the other of the second source electrode and the second drain electrode;

forming a third conductive film over the third insulating film so as to cover the third opening;

forming a fifth resist mask over the third conductive film; and

forming a pixel electrode by selectively etching the third conductive film with the use of the fifth resist mask.

16. The method for manufacturing a semiconductor device according to claim 15 further comprising the steps of:

forming a fourth insulating film so as to cover the second opening, the third opening, and a periphery of the pixel electrode; and

forming a layer including a light-emitting element over the pixel electrode.

17. The method for manufacturing a semiconductor device according to claim 15, wherein the semiconductor film is an oxide semiconductor.

18. The method for manufacturing a semiconductor device according to claim 15, wherein the first conductive film and the second conductive film are formed using a material containing aluminum.

19. The method for manufacturing a semiconductor device according to claim 18, wherein a maximum temperature of a heat treatment after the first conductive film or the second conductive film is formed is 380°

C. or lower.

20. The method for manufacturing a semiconductor device according to claim 15, wherein the first conductive film and the second conductive film are formed using a material containing copper.

21. The method for manufacturing a semiconductor device according to claim 20, wherein a maximum temperature of a heat treatment after the first conductive film or the second conductive film is formed is 450°

C. or lower.

22. A method for manufacturing a light-emitting display device, comprising the steps of:

forming a gate electrode over a substrate;

forming a first insulating film over the gate electrode;

forming a semiconductor film over the first insulating film;

forming a source electrode and a drain electrode over the semiconductor film;

forming a second insulating film over the source electrode and the drain electrode; and

through a photolithography process, forming a contact hole in the second insulating film by removing a first part of the second insulating film, and forming a patterned semiconductor film by removing a second part of the second insulating film and a part of the semiconductor film so as to expose a top surface of a part of the first insulating film; and

forming a pixel electrode over the second insulating film so as to cover the contact hole,

wherein the first part of the second insulating film overlaps with the drain electrode, and

wherein the second part of the second insulating film, the part of the semiconductor film and the part of the first insulating film do not overlap with the source electrode and the drain electrode.

23. The method for manufacturing a light-emitting display device according to claim 22, wherein the semiconductor film is an oxide semiconductor.

24. The method for manufacturing a light-emitting display device according to claim 22, wherein the gate electrode is formed using a material containing aluminum.

25. The method for manufacturing a light-emitting display device according to claim 24, wherein a maximum temperature of a heat treatment after the gate electrode is formed is 380°

C. or lower.

26. The method for manufacturing a light-emitting display device according to claim 22, wherein the gate electrode is formed using a material containing copper.

27. The method for manufacturing a light-emitting display device according to claim 26, wherein a maximum temperature of a heat treatment after the gate electrode is formed is 450°

C. or lower.