MANUFACTURE OF HIGH-M.P. METAL GATE ELECTRODE AND INVERTED T-SHAPED HIGH-M.P. METAL GATE

摘要

PURPOSE: To provide a method of manufacturing an MOS transistor, having an inverted T-shaped high-m.p. metal gate. ;CONSTITUTION: This gate comprises a main CVD W layer 14A and lower sputtered W layer 16A, extending from the bottom of a CVD part to the outside, so that the gate section becomes like an inverted T-shape. To etch the CVD W layer, a Cl₂/O₂ plasma etching is used. To etch the sputtered W layer for forming gate electrodes, a chemical etching is used. The sputtered W is etched to a lesser degree by the Cl₂/O₂ reactive plasma etching than by the CVD W. The sputtered W layer acts as a shield to prevent a lower oxide layer 10 from the ion damages during manufacturing.;COPYRIGHT: (C)1994,JPO