Manufacture of field-effect transistor

Abstract

Abstract PURPOSE:To form two-stage recesses excellent in the reproducibility and controllability of a shape and size, and to equalize characteristics by selectively implanting the ions of an impurity to a semiconductor substrate in a gate- electrode forming predetermined region and breaking the crystallizability of the substrate and shaping multistage recesses by utilizing the difference of etching rates generated as the result of the breaking of the crystallizability. CONSTITUTION:An insulating layer 104 and a photo-resist layer 11 with an opening section 11a are formed onto the surface of an N-type operating layer 102, and an opening section 114 wider than the opening section 11a is shaped to the insulating layer 104, using the photo-resist layer 11 as a mask. Ions are implanted into a gate-electrode forming predetermined region in the N-type operating layer 102 through the opening section 11a in the photo-resist layer 11 to form a crystal braking layer 12. The surface of the N-type operating layer 102 is etched through the opening sections 11a, 114 in the photo-resist layer 11 and the insulating layer 104, and the crystal breaking layer 12 and the N-type operating layer 102 not crystal-broken are removed, thus shaping multistage recesses 22. A gate electrode 105G is formed through a lift-off method through the photo-resist layer 11.

Inventors

• 👤 Masayoshi Miyauchi

Bibliographic Details