Liquid crystal display device and method of fabricating the same

1. A method of fabricating a liquid crystal display device, the method comprising:

sequentially forming a data bus line, an interlayer insulating layer, a semiconductor layer, a gate insulating layer, and a gate electrode on a first surface of a substrate;

forming a passivation layer on the substrate;

forming a photoresist film on the passivation layer;

forming a photoresist pattern from the photoresist film to expose portions of the passivation layer;

etching the passivation layer to form a plurality of first contact holes exposing portions of the semiconductor layer and etching the passivation layer, the gate insulating layer and the interlayer insulating layer to form a second contact hole exposing a portion of the data bus line, the first and second contact holes exposing the lower surface of the photoresist pattern;

depositing a first portion of a metal film on the photoresist pattern and a plurality of second portions of the metal film within each of the first and second contact holes;

removing the photoresist pattern and the first portion of the first metal film to leave the second portions of the first metal film within each of the first and second contact holes;

forming a transparent electrode material on the passivation film; and

patterning the transparent electrode material to form a pixel electrode within a first one of the plurality of first contact holes, and to form a source electrode having a first portion formed within a second one of the plurality of first contact holes and a second portion formed within the second contact hole wherein the metal film contacts the data bus line and the semiconductor layer through at least one of the contact holes.

2. The method according to claim 1 , wherein forming the interlayer insulating layer comprises:

forming a preliminary interlayer insulating layer having a first thickness on the data bus line and the substrate; and

etching the preliminary interlayer insulating layer to a second thickness less than the first thickness, the preliminary interlayer insulating layer having a planarized upper surface parallel to the first surface of the substrate.

3. The method according to claim 1 , wherein the interlayer insulating layer includes at least one selected from a group consisting of SOG (Spin on glass), SiNx, SiOx, and PE-oxide.

4. The method according to claim 1 , wherein a first one of the second portions of the first metal film is disposed within the first one of the plurality of first contact holes between the pixel electrode and the semiconductor layer, a second one of the second portions of the first metal film is disposed within the second one of the plurality of first contact holes between the second portion of the source electrode and the semiconductor layer, and a third one of the second portions of the first metal film is disposed within the second contact hole between the first portion of the source electrode and the data bus line.

5. The method according to claim 1 , wherein portions of the first metal film are not formed at the undercut regions of the photoresist pattern.

6. The method according to claim 1 , wherein the metal film includes an oxidation-resistant metal.

7. The method according to claim 6 , wherein the metal film is formed of one selected from a group consisting of Cr, Mo, W, Ti-based material, and an aluminum alloy.

8. A method of fabricating a liquid crystal display device, the method comprising:

forming a data bus line on a substrate;

forming a preliminary interlayer insulating layer having a first thickness on the substrate including the data bus line;

forming an interlayer insulating layer by etching the preliminary interlayer insulating layer to a second thickness less than the first thickness, the interlayer insulating layer having a planarized surface;

sequentially forming a semiconductor layer, a gate insulating layer, and a gate electrode on the interlayer insulating layer;

forming a passivation layer on the substrate;

forming a plurality of contact holes exposing portions of the data bus line and the semiconductor layer by etching portions of the passivation layer; and

forming a pixel electrode on the passivation layer.

9. The method according to claim 8 , wherein the forming a plurality of contact holes comprises:

coating a photoresist film on the passivation layer;

forming a photoresist pattern having a plurality of via holes over the data bus line and portions of the semiconductor layer;

etching the portions of the passivation layer to form the plurality of contact holes to expose the portions of the data bus line and the semiconductor layer;

depositing a metal film having a first portion on the photoresist pattern, second portions within each of the via holes, and a third portion within each of the contact holes; and

removing the photoresist pattern and the first and second portions of the metal film leaving the third portions of the metal film within each of the contact holes.

10. The method according to claim 9 , wherein the interlayer insulating layer includes at least one selected from a group consisting of SOG (Spin on glass), SiNx, SiOx, and PE-oxide.

11. The method according to claim 9 , wherein the plurality of contact holes include a first contact hole that exposes a portion of the data bus line, and second and third contact holes that expose portions of the semiconductor layer.

12. The method according to claim 9 , wherein the forming a plurality of contact holes includes formation of an undercut region of the photoresist pattern within each of the contact holes.

13. The method according to claim 12 , wherein the metal film is excluded from the undercut regions of the photoresist pattern.

14. The method according to claim 9 , wherein the metal film includes an oxidation-resistant material.

15. The method according to claim 14 , wherein the metal film includes one selected from a group consisting of Cr, Mo, W, Ti-based material, and an aluminum alloy.