<p>A method for forming a semiconductor device is provided to form a gate pattern with a fine line width by forming a conformal polysilicon layer to form a fine trench. A second polysilicon layer is formed on a semiconductor substrate(100). First hard mask patterns(110) are formed on the semiconductor substrate. The first hard mask patterns are conformally covered with a first polysilicon layer(120). Second hard mask patterns(130) contact with the lateral surface of the first polysilicon layer between the first hard mask patterns. The first polysilicon layer between the first hard mask patterns and the second hard mask patterns is removed to expose the semiconductor substrate. Trenches(140) are formed in the exposed semiconductor substrate by using the first and second hard mask patterns as a mask. The first and second hard mask patterns are made of a silicon nitride layer or a silicon oxynitride layer.</p>
