Method for forming pattern, thin film transistor, display device, method for manufacturing thereof, and television apparatus

• US 20050221203A1
• Filed: 03/22/2005
• Published: 10/06/2005
• Est. Priority Date: 03/24/2004
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Fujii, Gen
• Granted Patent: US 7,642,038 B2
• Time in Patent Office: Days
• US Class Current: 430/5
• CPC Class Codes: G03F 7/0043 Chalcogenides; Silicon, germanium, arsenic or derivatives thereof; Metals, oxides or alloys thereof G03F7/0044 takes precedence
• CPC Class Codes: G03F 7/201 characterised by an oblique exposure; characterised by the use of plural sources; characterised by the rotation of the optical device; characterised by a relative movement of the optical device, the light source, the sensitive system or the mask
• CPC Class Codes: H01L 21/28008 Making conductor-insulator-semiconductor electrodes
• CPC Class Codes: H01L 21/32051 Deposition of metallic or metal-silicide layers
• CPC Class Codes: H01L 27/1285 using control of the annealing or irradiation parameters, e.g. using different scanning direction or intensity for different transistors
• CPC Class Codes: H01L 27/1292 using liquid deposition, e.g. printing
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/66765 Lateral single gate single channel transistors with inverted structure, i.e. the channel layer is formed after the gate

Abstract

To provide a display device which can be manufactured with higher efficiency in the use of material through a simplified manufacturing process, and a method for manufacturing the display device. Another object is to provide a technique by which patterns of a wiring the like which constitutes the display device can be formed to a desired shape with good control. In a method for forming a pattern according to the present invention, a mask is formed over a light-transmitting substrate; a first region including a photocatalyst is formed over the substrate and the mask; the photocatalyst is irradiated with light through the substrate to modify a part of the first region; a second region is formed; and a composition containing a pattern forming material is discharged to the second region, thus, a pattern is formed. The mask does not transmit light.

Claims

1. A method for forming a pattern, comprising the steps of:

forming a mask over a light-transmitting substrate;

forming a first region including a photocatalyst over the substrate and the mask;

irradiating the photocatalyst with light through the substrate to modify a part of the first region which is to be a second region; and

discharging a composition containing a pattern forming material to the second region to form a pattern,

wherein the mask does not transmit the light.

2. A method according to claim 1, wherein titanium oxide is used as the photocatalyst to form the first region.

3. A method according to claim 1, wherein a surface of the material containing the fluorocarbon chain is modified so that the second region has higher wettability with the composition than the first region.

4. A method for forming a pattern, comprising the steps of:

forming a mask over a light-transmitting substrate;

forming a first region including a photocatalyst over the substrate and the mask;

forming a material containing a fluorocarbon chain over the photocatalyst;

irradiating the photocatalyst and the material containing the fluorocarbon chain with light through the substrate to modify a part of a surface of the material containing the fluorocarbon chain which is to be a second region; and

discharging a composition containing a pattern forming material to the second region to form a pattern,

wherein the mask does not transmit the light.

5. A method according to claim 4, wherein titanium oxide is used as the photocatalyst to form the first region.

6. A method according to claim 4, wherein a surface of the material containing the fluorocarbon chain is modified so that the second region has higher wettability with the composition than the first region.

7. A method for manufacturing a thin film transistor, comprising the steps of:

forming a first conductive layer over a light-transmitting substrate;

forming an insulating layer over the substrate and the first conductive layer;

forming a first region including a photocatalyst over the insulating layer;

irradiating the photocatalyst with light through the substrate to modify a part of the first region which is to be a second region; and

discharging a composition containing a conductive material to the second region to form a second conductive layer,

wherein the first conductive layer does not transmit light.

8. A method according to claim 7, wherein titanium oxide is used as the photocatalyst to form the first region.

9. A method according to claim 7, wherein a surface of the material containing the fluorocarbon chain is modified so that the second region has higher wettability with the composition than the first region.

10. A method according to claim 7, wherein the first conductive layer is formed as a gate electrode layer and the second conductive layer is formed as a source electrode layer and a drain electrode layer.

11. A method for manufacturing a thin film transistor, comprising the steps of:

forming a first conductive layer over a light-transmitting substrate;

forming an insulating layer over the substrate and the first conductive layer;

forming a first region including a photocatalyst over the insulating layer;

forming a material containing a fluorocarbon chain over the photocatalyst;

irradiating the photocatalyst and the material containing the fluorocarbon chain with light through the substrate to modify a part of a surface of the material containing the fluorocarbon chain which is to be a second region; and

discharging a composition containing a conductive material to the second region to form a second conductive layer,

wherein the first conductive layer does not transmit light.

12. A method according to claim 11, wherein titanium oxide is used as the photocatalyst to form the first region.

13. A method according to claim 11, wherein a surface of the material containing the fluorocarbon chain is modified so that the second region has higher wettability with the composition than the first region.

14. A method according to claim 11, wherein the first conductive layer is formed as a gate electrode layer and the second conductive layer is formed as a source electrode layer and a drain electrode layer.

15. A thin film transistor comprising:

a first conductive layer provided over a light-transmitting substrate;

an insulating layer over the substrate and the first conductive layer;

a photocatalyst provided over the insulating layer;

a material containing a fluorocarbon chain over the photocatalyst;

a first region and a second region in a surface of the material containing the fluorocarbon chain; and

a second conductive layer over the second region,

wherein density of the fluorocarbon chain contained in the first region is higher than density of the fluorocarbon chain contained in the second region.

16. A thin film transistor according to claim 15, wherein the photocatalyst is titanium oxide.

17. A thin film transistor comprising:

a first conductive layer provided over a light-transmitting substrate;

an insulating layer over the substrate and the first conductive layer;

a photocatalyst provided over the insulating layer;

a material containing a fluorocarbon chain over the photocatalyst;

a first region and a second region are in a surface of the material containing the fluorocarbon chain;

a second conductive layer provided over the second region; and

a semiconductor layer formed over the material containing the fluorocarbon chain and the second electrode layer,

wherein density of the fluorocarbon chain contained in the first region is higher than density of the fluorocarbon chain contained in the second region.

18. A thin film transistor according to claim 17, wherein the photocatalyst is titanium oxide.

19. A display device comprising:

a gate electrode layer provided over a light-transmitting substrate;

an insulating layer over the substrate and the gate electrode layer;

a photocatalyst provided over the insulating layer;

a material containing a fluorocarbon chain over the photocatalyst;

a first region and a second region in a surface of the material containing the fluorocarbon chain; and

a source electrode layer and a drain electrode layer over the second region,

wherein density of the fluorocarbon chain contained in the first region is higher than density of the fluorocarbon chain contained in the second region.

20. A display device according to claim 19, wherein the photocatalyst is titanium oxide.

21. A display device comprising:

a gate electrode layer provided over a light-transmitting substrate;

an insulating layer over the substrate and the gate electrode layer;

a photocatalyst provided over the insulating layer;

a material containing a fluorocarbon chain over the photocatalyst;

a first region and a second region in a surface of the material containing the fluorocarbon chain;

a source electrode layer and a drain electrode layer over the second region; and

a semiconductor layer formed over the material containing the fluorocarbon chain and the source electrode layer and the drain electrode layer,

wherein density of the fluorocarbon chain contained in the first region is higher than density of the fluorocarbon chain contained in the second region.

22. A display device according to claim 21, wherein the photocatalyst is titanium oxide.

23. A television apparatus comprising a display screen constituted by a display device;

the display device including;

a gate electrode layer provided over a light-transmitting substrate;

an insulating layer over the substrate and the gate electrode layer;

a photocatalyst provided over the insulating layer;

a material containing a fluorocarbon chain over the photocatalyst, and

a first region and a second region in a surface of the material containing the fluorocarbon chain; and

a source electrode layer and a drain electrode layer over the second region,

wherein density of the fluorocarbon chain contained in the first region is higher than density of the fluorocarbon chain contained in the second region.

24. A display device according to claim 23, wherein the photocatalyst is titanium oxide.

25. A television apparatus comprising a display screen constituted by a display device;

the display device including;

a gate electrode layer provided over a light-transmitting substrate;

an insulating layer over the substrate and the gate electrode layer;

a photocatalyst provided over the insulating layer;

a material containing a fluorocarbon chain over the photocatalyst,

a first region and a second region in a surface of the material containing the fluorocarbon chain,

a source electrode layer and a drain electrode layer over the second region; and

a semiconductor layer formed over the material containing the fluorocarbon chain and the source electrode layer and the drain electrode layer,

wherein density of the fluorocarbon chain contained in the first region is higher than density of the fluorocarbon chain contained in the second region.

26. A display device according to claim 25, wherein the photocatalyst is titanium oxide.