Method for forming fine pattern of semiconductor device

A method for manufacturing a fine pattern of a semiconductor device, the method comprising:

• forming a hard mask pattern having a first pitch and a thickness of t1 over an underlying layer, the hard mask pattern including a first structure and a second structure, the underlying layer disposed over a semiconductor substrate;
• forming a light penetrable thin film having a thickness of t2 over the hard mask pattern and the underlying layer;
• forming a light absorbable thin film over the light penetrable thin film, the light absorbable thin film having a substantially planar upper surface;
• performing an exposure process on the light absorbable thin film, the light penetrable thin film, and the hard mask pattern without using an exposure mask, the exposure process involving controlling an amount of exposure energy such that a light reaches to a depth T measured from a top surface of the light penetrable thin film disposed over the hard mask patterns to a top surface of the underlying layer, wherein t2 <T≦t1+t2;
• thereafter, performing a developing process to form an additional pattern disposed between the first and second structures of the hard mask pattern, the additional pattern comprising including a portion of the light penetrable thin film and a portion the light absorbable thin film;
• and
• etching the underlying layer using the hard mask patterns and the additional pattern as an etching mask, the underlying layer being provided with an underlying pattern having a second pitch that is less than the first pitch.