Semiconductor device having a two layered structure gate electrode

Abstract

A semiconductor device not aggravated in transistor characteristic even when an impurity region is formed by ion implantation using a gate electrode as a mask, and a method of manufacturing thereof are disclosed. The semiconductor device includes a gate electrode 10 implemented by a polycrystal silicon layer 4 having the crystal orientation of the crystal grains thereof arranged in a predetermined orientation, and a single crystal silicon layer 5 formed on the polycrystal silicon layer 4 having a crystal orientation identical to that of the polycrystal silicon layer 4. The channelling phenomenon in which B.sup.+ ions pass through to beneath the gate electrode 10 is prevented in forming an impurity region 6 by ion implantation to obtain a semiconductor device that does not have the characteristic of the formed transistor aggravated.

Dependencies are inferred from the claim text.