Transparent thin film having conductive and nonconductive portions, method of patterning the portions, thin-film transistor array substrate including the thin film and method of manufacturing the same

• US 9,000,439 B2
• Filed: 11/15/2012
• Issued: 04/07/2015
• Est. Priority Date: 04/06/2012
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Lee, Dae-Young, Lee, Ki-Beom, Kim, Kyu-Young, Jung, Nam-Ok, Jo, Gug-Rae
• Primary Examiner(s): Nguyen, Cuong Q
• Assistant Examiner(s): Gebreyesus, Yosef
• Application Number:
  US13/678,313
• Publication Number:
  US 20130264572A1
• Time in Patent Office: 873 Days
• Field of Search: 257/59, 257/72, 257/88, 257/E33.053, 257/E31.126, 257/E33.068
• US Class Current: 257/59
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: H01L 21/28 Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/268 etching for patterning the electrodes H01L21/311, H01L21/3213; multistep manufacturing processes for data storage electrodes H01L29/4011
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H05K 1/02 Details
• CPC Class Codes: H05K 1/09 Use of materials for the conductive, e.g. metallic pattern

Abstract

A homogenous thin film layer is patterned into a transparent conductive portion and a non-conductive portion without use of etching through the thin film. Instead, conductive fine-wires which are convertible in one embodiment into non-conductive fine-wires are selectively converted into the non-conductive form. In an alternate embodiment, the homogenous thin film layer which includes conductive fine-wires is provided in a curable liquid form and selected portions of the liquid formed are cured into being affixed to substrate. Remaining portions can be washed away. In the case of display devices using transparent electrodes, a thin thin-film transistor array substrate is provided where the initially homogenous thin film which is and then converted into patterned conductive and non-conductive sections forms the pixel-electrodes and/or common electrode of the display device.

Claims

1. A thin film disposed as a layer on a substrate, the thin film comprising:

a patterned transparent electrode portion comprised of a plurality of conductive fine-wires; and

a patterned non-conductive sub-portion disposed in the same layer as that of the patterned transparent electrode portion, the non-conductive sub-portion including at least one member selected from the group of non-conductive fine-wires consisting of oxidized fine-wires, chloridated fine-wires and fluoridated fine-wires.

2. The thin film of claim 1, wherein the conductive fine-wires comprise at least one of silver-containing fine-wires and copper-containing fine-wires.

3. The thin film of claim 1, wherein an optical transmittance efficiency of the transparent electrode portion is in a range from about 85% to about 95% with respect to a light having a wavelength of about 550 nm.

4. The thin film of claim 1, wherein a surface resistivity of the transparent electrode pattern is from about 15Ω

/□

(ohms per square) to about 110Ω

/□

, and a surface resistance of the non-conductive sub-portion is greater than about 1 MΩ

/□

.

5. The thin film of claim 1, wherein the electrode pattern is in physical contact with the non-conductive sub-portion.

6. A method of patterning a thin film, the method comprising:

forming a homogenous and transparent thin layer having conductive fine-wires on a substrate; and

converting a portion of the formed and homogenous transparent thin layer into a non-conductive sub-portion having a desired pattern where the non-conductive sub-portion includes at least one member selected from the group of non-conductive fine-wires consisting of oxidized fine-wires, chloridated fine-wires and fluoridated fine-wires.

7. The method of claim 6, wherein the conversion which forms the non-conductive sub-portion comprises:

forming a gas impermeable and patterned mask that protects at least a first area of the transparent thin layer from being subjected to a corresponding gas; and

providing as the corresponding gas, a reactive gas to a second area of the transparent thin layer not protected by the gas impermeable and patterned mask, where the reactive gas chemically modifies the fine-wires of the second area into becoming non-conductive fine-wires.

8. The method of claim 6, wherein the conversion which forms the non-conductive sub-portion includes:

selectively irradiating portions of the transparent thin layer with a laserfine-wires.

9. The method of claim 8, wherein a wavelength of the laser is from about 330 nm to about 500 nm, and the laser radiation is a pulsed one in which a unit of a pulse length of the laser is about one Pico second.

10. A method of forming a patterned thin film, the method comprising:

forming on a substrate, a homogenous and transparent thin film layer having conductive fine-wires mixed with a liquid polymer precursor composition;

forming a light blocking and patterned mask that protects at least a first area of the transparent thin layer from exposure to a precursor curing light;

irradiating a precursor curing light onto a second portion of the transparent thin layer not protected by the patterned mask; and

selectively removing from the exposed transparent thin layer, the uncured mixture of conductive fine-wires and the polymer precursor composition of the second area.

11. The method of claim 10, wherein the polymer precursor composition comprises:

a mono-functional monomer of about 10 weight % to about 20 weight % with respect to a total weight of the polymer precursor composition;

a dual-functional monomer of about 20 weight % to about 60 weight % with respect to the total weight of the polymer precursor composition;

a multi-functional monomer of about 10 weight % to about 30 weight % with respect to the total weight of the polymer precursor composition;

a photo initiator of about 3 weight % to about 5 weight % with respect to the total weight of the polymer precursor composition; and

a solvent whose weight is not counted as part of said total weight of the polymer precursor composition.

12. A thin-film transistor array substrate comprising:

a gate line formed on a base substrate;

a data line extended in a direction crossing the gate line;

a thin-film transistor connected to the gate line and the data line; and

a pixel electrode including;

a transparent electrode pattern formed in a layer and having conductive fine-wires; and

a non-conductive sub-portion disposed in the same layer as the transparent electrode pattern, the non-conductive sub-portion including at least one member selected from the group of non-conductive fine-wires consisting of oxidized fine-wires, chloridated fine-wires or fluoridated fine-wires.

13. The thin-film transistor substrate of claim 12, wherein the conductive fine-wires comprise at least one of silver and copper.

14. The thin-film transistor substrate of claim 12, wherein an optical transmittance efficiency of the transparent electrode pattern is from about 85% to about 95% with respect to a light having a wavelength of about 550 nm.

15. The thin-film transistor substrate of claim 12, wherein a surface resistivity of the transparent electrode pattern is from about 15Ω

/□

to about 110Ω

/□

, and a surface resistance of the non-conductive sub-portion is greater than about 1 MΩ

/□

.

16. A method of manufacturing a thin-film transistor substrate, the method comprising:

forming on a substrate, a gate line, a data line and a thin-film transistor, the data line being extended in a direction crossing the gate line, the thin-film transistor being connected to the gate line and the data line; and

forming on the substrate, a pixel electrode that includes a transparent electrode portion having conductive fine-wires, and that includes a non-conductive sub-portion, the non-conductive sub-portion comprising at least one member selected from the group of non-conductive fine-wires consisting of oxidized fine-wires, chloridated fine-wires.

17. The method of claim 16, wherein the forming of the pixel electrode comprises:

forming a homogenous and transparent thin layer having the conductive fine-wires, the homogenous and transparent thin layer being formed on a base substrate on which the switching device is already formed;

forming a gas impermeable and patterned mask that protects at least a first area of the transparent thin layer from being subjected to a corresponding gas; and

providing as the corresponding gas, a reactive gas to a second area of the transparent thin layer not protected by the gas impermeable and patterned mask, where the reactive gas chemically modifies the fine-wires of the second area into becoming non-conductive fine-wires.

18. The method of claim 16, wherein the non-conductive sub-portion is formed by irradiating a pulsed laser onto a portion of the transparent thin layer, and where a unit of a pulse length of the pulse laser is about one Pico second.

19. A method of manufacturing thin-film transistor substrate, the method comprising:

forming a gate line, a data line and a thin-film transistor on a base substrate, the data line being extended in a direction crossing the gate line, the thin-film transistor being connected to the data line and the gate line;

forming on the base substrate having the formed thin-film transistor, a homogenous transparent thin film layer having a mixture of conductive fine-wires and a liquid polymer precursor composition;

forming a photo pattern over the transparent thin film layer where the photo pattern blocks a supplied curing light from reaching a first area of the transparent thin film layer and allows the supplied curing light to reach a second area of the transparent thin film layer;

irradiating a curing light through the photo pattern and onto the exposed second area of the transparent thin film layer; and

selectively removing from the irradiated transparent thin film layer, the uncured mixture of conductive fine-wires and the polymer precursor composition of the second area fine-wires.

20. The method of claim 19, wherein the polymer precursor composition comprising:

a mono-functional monomer of about 10 weight % to about 20 weight % with respect to a total weight of the polymer precursor composition;

a dual-functional monomer of about 20 weight % to about 60 weight % with respect to the total weight of the polymer precursor composition;

a multi-functional monomer of about 10 weight % to about 30 weight % with respect to the total weight of the polymer precursor composition;

a photo initiator of about 3 weight % to about 5 weight % with respect to the total weight of the polymer precursor composition; and

an extra solvent.