Manufacturing method of display device

• US 20090029498A1
• Filed: 07/18/2008
• Published: 01/29/2009
• Est. Priority Date: 07/27/2007
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Arai, Yasuyuki, Yamazaki, Shunpei
• Granted Patent: US 8,178,398 B2
• Time in Patent Office: Days
• US Class Current: 438/30
• CPC Class Codes: C23C 16/511 using microwave discharges
• CPC Class Codes: H01J 37/32192 Microwave generated discharge H01J37/32357, H01J37/32366, H01J37/32394, H01J37/32403 take precedence

Abstract

To improve a deposition rate of a microcrystalline semiconductor layer by using a deposition method and to improve productivity of a display device including a TFT of a microcrystalline semiconductor, a reactive gas containing helium is supplied to a treatment chamber surrounded with a plurality of juxtaposed waveguides and a wall surface; a microwave is supplied to a space which is interposed between juxtaposed waveguides to generate plasma while the pressure of the treatment chamber is held at an atmospheric pressure or a sub-atmospheric pressure typically a pressure of 1×10² Pa or more and 1×10⁵ Pa or less; and a microcrystalline semiconductor layer is deposited over a substrate placed in the treatment chamber. High density plasma is generated by providing slits on sides of the plurality of juxtaposed waveguides which face to another waveguide and supplying a microwave into the treatment chamber through the slit.

Claims

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

supplying a reactive gas containing helium to a treatment chamber provided with a plurality of waveguides aligned to extend in a comb shape in the treatment chamber; and

forming a microcrystalline semiconductor layer over a substrate placed in the treatment chamber by supplying a microwave to space between the plurality of waveguides, to generate plasma while holding the pressure of the treatment chamber at a pressure of 1×

10² Pa or more and 1×

10⁵ Pa or less.

2. The method for manufacturing a display device according to claim 1, wherein the plasma has an electron density of 1×

10¹¹ cm<sup>−

3</sup> or more and 1×

10¹³ cm<sup>−

3</sup> or less and an electron temperature of 0.2 eV or more and 2.0 eV or less.

3. The method for manufacturing a display device according to claim 1,

wherein the plurality of waveguides each have a slit,

wherein the slit is provided on each side on which the plurality of aligned waveguides face to each other, and

wherein the microwave is supplied from the slit.

4. The method for manufacturing a display device according to claim 3,

wherein the slit is clogged with a dielectric plate.

5. The method for manufacturing a display device according to claim 1,

wherein the reactive gas containing helium contains helium and a semiconductor material gas,

wherein the treatment chamber is provided with a plurality of nozzles, and

wherein the helium is configured to flow from one of the plurality of nozzles and the semiconductor material gas is configured to flow from another of the plurality of nozzles.

6. The method for manufacturing a display device according to claim 1,

wherein the display device is a liquid crystal display device.

7. A method for manufacturing a display device comprising the steps of:

supplying a reactive gas containing helium to a treatment chamber provided with a plurality of waveguides aligned to extend in a comb shape in the treatment chamber;

forming a gate insulating layer;

forming a microcrystalline semiconductor layer over a substrate placed in the treatment chamber by supplying a microwave to space between the plurality of waveguides, to generate plasma while holding the pressure of the treatment chamber at a pressure of 1×

10² Pa or more and 1×

10⁵ Pa or less; and

forming an impurity semiconductor layer,

wherein the gate insulating layer, the microcrystalline semiconductor layer, and the impurity semiconductor layer are successively formed over a gate electrode, and

wherein the interfaces among the gate insulating layer, the microcrystalline semiconductor layer, and the impurity semiconductor layer are not exposed to the atmosphere.

8. The method for manufacturing a display device according to claim 7, wherein the plasma has an electron density of 1×

10¹¹ cm<sup>−

3</sup> or more and 1×

10¹³ cm<sup>−

3</sup> or less and an electron temperature of 0.2 eV or more and 2.0 eV or less.

9. The method for manufacturing a display device according to claim 7,

wherein the plurality of waveguides each have a slit,

wherein the slit is provided on each side on which the plurality of aligned waveguides face to each other, and

wherein the microwave is supplied from the slit.

10. The method for manufacturing a display device according to claim 9,

wherein the slit is clogged with a dielectric plate.

11. The method for manufacturing a display device according to claim 7,

wherein the reactive gas containing helium contains helium and a semiconductor material gas,

wherein the treatment chamber is provided with a plurality of nozzles, and

wherein the helium is configured to flow from one of the plurality of nozzles and the semiconductor material gas is configured to flow from another of the plurality of nozzles.

12. The method for manufacturing a display device according to claim 7,

wherein the display device is a liquid crystal display device.

13. A method for manufacturing a display device comprising the steps of:

supplying a reactive gas containing helium to a treatment chamber provided with a plurality of waveguides aligned to extend in a comb shape in the treatment chamber; and

forming a microcrystalline semiconductor layer over a substrate placed in the treatment chamber by supplying a microwave to space between the plurality of waveguides, to generate plasma while holding the pressure of the treatment chamber at a pressure of 1×

10² Pa or more and 1×

10⁵ Pa or less,

wherein the helium is formed from the reactive gas passed through the treatment chamber by using a gas purification circulator.

14. The method for manufacturing a display device according to claim 13, wherein the plasma has an electron density of 1×

10¹¹ cm<sup>−

3</sup> or more and 1×

10¹³ cm<sup>−

3</sup> or less and an electron temperature of 0.2 eV or more and 2.0 eV or less.

15. The method for manufacturing a display device according to claim 13,

wherein the plurality of waveguides each have a slit,

wherein the slit is provided on each side on which the plurality of aligned waveguides face to each other, and

wherein the microwave is supplied from the slit.

16. The method for manufacturing a display device according to claim 15,

wherein the slit is clogged with a dielectric plate.

17. The method for manufacturing a display device according to claim 13,

wherein the reactive gas containing helium contains helium and a semiconductor material gas,

wherein the treatment chamber is provided with a plurality of nozzles, and

wherein the helium is configured to flow from one of the plurality of nozzles and the semiconductor material gas is configured to flow from another of the plurality of nozzles.

18. The method for manufacturing a display device according to claim 13,

wherein the display device is a liquid crystal display device.

19. A method for manufacturing a display device comprising the steps of:

supplying a reactive gas containing helium to a treatment chamber provided with a plurality of waveguides aligned to extend in a comb shape in the treatment chamber;

forming a gate insulating layer;

forming a microcrystalline semiconductor layer over a substrate placed in the treatment chamber by supplying a microwave to space between the plurality of waveguides, to generate plasma while holding the pressure of the treatment chamber at a pressure of 1×

10² Pa or more and 1×

10⁵ Pa or less; and

forming an impurity semiconductor layer,

wherein the gate insulating layer, the microcrystalline semiconductor layer, and the impurity semiconductor layer are successively formed over a gate electrode,

wherein the interfaces among the gate insulating layer, the microcrystalline semiconductor layer, and the impurity semiconductor layer are not exposed to the atmosphere, and

wherein the helium is formed from the reactive gas passed through the treatment chamber by using a gas purification circulator.

20. The method for manufacturing a display device according to claim 19, wherein the plasma has an electron density of 1×

10¹¹ cm<sup>−

3</sup> or more and 1×

10¹³ cm<sup>−

3</sup> or less and an electron temperature of 0.2 eV or more and 2.0 eV or less.

21. The method for manufacturing a display device according to claim 19,

wherein the plurality of waveguides each have a slit,

wherein the slit is provided on each side on which the plurality of aligned waveguides face to each other, and

wherein the microwave is supplied from the slit.

22. The method for manufacturing a display device according to claim 21,

wherein the slit is clogged with a dielectric plate.

23. The method for manufacturing a display device according to claim 19,

wherein the reactive gas containing helium contains helium and a semiconductor material gas,

wherein the treatment chamber is provided with a plurality of nozzles, and

wherein the helium is configured to flow from one of the plurality of nozzles and the semiconductor material gas is configured to flow from another of the plurality of nozzles.

24. The method for manufacturing a display device according to claim 19,

wherein the display device is a liquid crystal display device.