Fabricating method of polycrystalline silicon thin film transistor with improved electrical characteristics

1. A fabricating method of a polycrystalline silicon thin film transistor, comprising:

forming a polycrystalline silicon layer on a substrate having first and second regions through a crystallization process using nickel silicide (NiSi x ) as a catalyst;

patterning the polycrystalline silicon layer to form an active layer at the first region, leaving a nickel silicide residue at the second region;

etching the nickel silicide residue with a solution including hydrofluoric acid (HF) and hydrogen peroxide (H 2 O 2 ), wherein the solution includes about 3% to about 10% by weight of hydroflouric acid and about 1% to about 5% by weight of hydrogen peroxide;

forming a gate electrode over the active layer; and

forming a source and drain in the active layer.

2. The method according to claim 1 , wherein the solution includes about 5% by weight of hydrofluoic acid and about 3% by weight of hydrogen peroxide.

3. The method according to claim 2 , wherein etching the nickel silicide residue is performed for about 10 seconds.

4. The method according to claim 1 , wherein patterning the polycrystalline silicon layer is performed through a photolithographic process including forming a photoresist (PR) pattern on the polycrystalline silicon layer and etching the polycrystalline silicon layer by using the photoresist (PR) pattern as an etching mask.

5. The method according to claim 4 , wherein forming the photoresist (PR) pattern includes coating, exposure and development of a photoresist (PR).

6. The method according to claim 1 , wherein forming a polycrystalline silicon layer is performed through a field enhanced metal induced crystallization (FE-MIC) method using a heat energy and an electric field.