the fine pattern forming method includes the steps of applying an organic polymer film on a semiconductor substrate and heat treating the same ; applying a resin solution on the organic polymer layer and heat treating the same ; carrying out a heat treatment after a pattern is written , causing the generated acid to react with the acid degradation polymer or the acid reactive monomer and carrying out a development in an alkaline solution to form a resist pattern ; and etching the organic polymer layer using the resist pattern as a mask . the use of the resist layer including the silicone resin , the acid generator , and the acid degradation polymer or the acid reactive monomer enables an accurate fine resist pattern to be formed which has a high sensitivity and dry etching resistance , and in which charging is prevented when a pattern is written by a charged beam .