PURPOSE: To avoid charging up of the surface of a resist film caused by an electron beam or the like when a pattern is lithographed and eliminate a pattern shift caused by the warpage of the orbit of the applied electron beam or the like and facilitate forming a highly accurate pattern by a method wherein the surface of the resist film is made to be conductive by the application of low energy ion beams.

CONSTITUTION: A low energy ion beam 3 whose energy is high enough to make the surface of a resist film 2 sensitive to a charged particle beam 5 conductive is applied to at least the region of the resist film 2 to which the charged particle beam 5 is applied. Successively, the charged particle beam 5 is applied to the resist film 2 to lithograph a required pattern. For instance, the resist film 2 made of PMMA is formed on a semiconductor substrate 1 made of Si or the like and dried and baked. Then the semiconductor substrate 1 is placed in a vacuum and the argon ion beam 3 is applied to the whole surface. After the electron beam 5 is applied to the resist film 2 in which a conductive layer 4 is formed at the surface by a method described above for lithography of a pattern, the resist film is developed by MIBK to obtain the resist pattern 21.