PURPOSE: To form a reverse taper type window by using a simple means without using a surface modification means.

CONSTITUTION: A gate electrode forming part position 13 of a resist film 12 which is stuck and formed on a semiconductor substrate 11 is irradiated with an electron beam 14a. The electron beam 14a is reflected from the surface vicinity part position of the semiconductor substrate 11 and scattered. By the effect of scattering, the more part is exposed in the lower part than the surface part in the gate electrode forming part position 13. As the result, when the gate electrode forming part position 13 of the resist film 12 is dissolved and eliminated, and a window is formed, the sectional form of the window part 15 constitutes an inverse taper type. After that, by sputtering gate electrode material 16a, 16b, a gate electrode 17 is formed in the window part 15 in the step-cut state of the window part 15.