PURPOSE: To manufacture a groove, into which a source (or drain) electrode is inserted, easily and stably by a method wherein a film as a gate electrode is grown in the groove, a film having inferior coatability is formed on the surface of the film as the gate electrode, the groove bottom section of the film having inferior coatability is removed, and only the bottom of the film as the gate electrode is taken away, using the film having inferior coatability as a mask.

CONSTITUTION: A film 10 as a gate electrode is shaped on the whole surface of the inside of a groove 1a and a flat section in the vicinity of the inlet of the groove la, and a film 11 baving inferior coatability is formed on the surface of the film 10. Only the groove bottom of the film 11 is removed, and only the bottom 10a of the film 10 is gotten rid of, employing a residual film 111 in the flat section in the vicinity of the inlet of the groove as a mask, thus forming a gate electrode 10'. Poly Si 10 as the gate electrode is shaped onto the surface of the groove 1a of a substrate such as an Si substrate 1 through an SiO2 oxide film 2, and the film 11 such as an SiO2 film 11 is formed onto the surface of the poly Si 10 through a sputtering method. When etching the whole surface of the film 11, the SiO2 film having small film thickness in the surface of a base section 102 is removed. A poly Si bottom 10a, the surface of which has no SiO2 film, is taken off through anisotropic etching, employing the residual SiO2 film 111 as a mask, and the SiO2 film 111 is removed, thus completing the gate electrode 10.