Manufacturing method for a circuit pattern, a thin film transistor and an electronic appliance

• US 20070207274A1
• Filed: 03/01/2007
• Published: 09/06/2007
• Est. Priority Date: 03/02/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Fujii, Gen
• Granted Patent: US 7,820,465 B2
• Time in Patent Office: Days
• US Class Current: 427/532
• CPC Class Codes: C03C 17/42 at least one coating of an organic material and at least one non-metal coating
• CPC Class Codes: C23C 26/00 Coating not provided for in groups C23C2/00 - C23C24/00
• CPC Class Codes: C23C 28/00 Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
• CPC Class Codes: C23C 4/01 Selective coating, e.g. pattern coating, without pre-treatment of the material to be coated
• CPC Class Codes: H01C 17/06 adapted for coating resistive material on a base
• CPC Class Codes: H05K 2201/0108 Transparent
• CPC Class Codes: H05K 2203/0551 Exposure mask directly printed on the PCB
• CPC Class Codes: H05K 2203/1173 Differences in wettability, e.g. hydrophilic or hydrophobic areas
• CPC Class Codes: H05K 3/0082 characterised by the exposure method of radiation-sensitive masks
• CPC Class Codes: H05K 3/1208 Pretreatment of the circuit board, e.g. modifying wetting properties; Patterning by using affinity patterns providing shape patterns H05K3/1258; adhesion treatments H05K3/38
• CPC Class Codes: H05K 3/1241 by ink-jet printing or drawing by dispensing
• CPC Class Codes: H10K 71/13 using printing techniques, e.g. ink-jet printing or screen printing

Abstract

A circuit pattern is formed by following steps: forming a light-blocking mask over a major surface of a light-transmitting substrate, forming a first film in a first region over the substrate and the mask, forming a photocatalytic film in at least a part of the first region over the first film, changing wettability of the first film in a second region which is in the first region, being in contact with the photocatalytic film, and not overlapping the mask, by light irradiation from a back surface opposite to the major surface of the substrate, removing the photocatalytic film, and forming a composition including a pattern forming material in the second region.

Claims

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

forming a light-blocking mask over a major surface of a light-transmitting substrate;

forming a first film in a first region over the substrate and the mask;

forming a photocatalytic film in at least a part of the first region over the first film;

changing wettability of the first film in a second region which is in the first region, being in contact with the photocatalytic film, and not overlapping the mask, by light irradiation from a back surface opposite to the major surface of the substrate;

removing the photocatalytic film; and

forming a composition including a pattern forming material in the second region.

3. The method for forming the circuit pattern according to claim 1, wherein wettability with respect to the composition of the second region is higher than that of the first region.

5. The method for forming the circuit pattern according to claim 1, wherein the photocatalytic film comprises zinc oxide.

7. The method for forming the circuit pattern according to claim 1, wherein the first film comprises alkylsilane or fluoroalkylsilane.

9. The method for forming the circuit pattern according to claim 1, wherein the light has a wavelength of 380 nm or less.

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

forming a light-blocking mask over a major surface of a light-transmitting substrate;

forming an insulating layer over the substrate and the mask;

forming a first film in a first region over the insulating layer;

forming a photocatalytic film in at least a part of the first region over the first film;

changing wettability of the first film in a second region which is in the first region, being in contact with the photocatalytic film, and not overlapping the mask, by light irradiation from a back surface opposite to the major surface of the substrate;

removing the photocatalytic film; and

forming a composition including a pattern forming material in the second region.

4. The method for forming the circuit pattern according to claim 2, wherein wettability with respect to the composition of the second region is higher than that of the first region.

6. The method for forming the circuit pattern according to claim 2, wherein the photocatalytic film comprises zinc oxide.

8. The method for forming the circuit pattern according to claim 2, wherein the first film comprises alkylsilane or fluoroalkylsilane.

10. The method for forming the circuit pattern according to claim 2, wherein the light has a wavelength of 380 nm or less.

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

forming a light-blocking first conductive layer over a major surface of a light-transmitting substrate;

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

forming a first film in a first region over the insulating layer;

forming a photocatalytic film in at least a part of the first region over the first film;

changing wettability of the first film in a second region which is in the first region, being in contact with the photocatalytic film, and not overlapping the first conductive layer, by light irradiation from a back surface opposite to the major surface of the substrate;

removing the photocatalytic film; and

forming a composition including a second conductive layer forming material in the second region.

12. The method for forming the thin film transistor according to claim 11, wherein wettability with respect to the composition of the second region is higher than that of the first region.

13. The method for forming the thin film transistor according to claim 11, wherein the photocatalytic film comprises zinc oxide.

14. The method for forming the thin film transistor according to claim 11, wherein the first film comprises alkylsilane or fluoroalkylsilane.

15. The method for forming the thin film transistor according to claim 11, wherein the light has a wavelength of 380 nm or less.

16. The method for forming the thin film transistor according to claim 11, wherein the first conductive layer is a gate electrode layer and the second conductive layer is a source electrode or drain electrode layer.

17. A method for forming an electronic appliance including the thin film transistor according to claim 11, further comprising a step of incorporating the thin film transistor into the electronic appliance.

18. The method for forming the electronic appliance according to claim 17, wherein the electronic appliance is any one of a video camera, a digital camera, a projector, a head mounted display, a car navigation system, a car stereo, a personal computer, a game machine, a portable information terminal, or an image reproducing device provided with a recording medium.