| 摘要 |
PURPOSE:To provide a method of manufacturing a mask ROM low in leakage and contact resistance and high in threshold voltage margin, wherein the delivery time can be shortened. CONSTITUTION:In a method of manufacturing a semiconductor device such as a mask ROM wherein data are written through an ion implantation method, a high melting point metal 6 is deposited on a gate electrode 3 and an insulating film 5, ROM data are written by implanting ions through a mask pattern 9 as a mask, impurities are introduced into a channel part of a transistor through the intermediary of the high melting point metal 6, the insulating film 5, and the gate electrode 3, and thereafter an annealing process is carried out at a comparatively high temperature to change the semiconductor device in threshold voltage. |
