| 摘要 |
PURPOSE:To obtain a source and a drain by nitriding the surface layer of an electrode wiring comprising high-melting-point metal such as Mo and the like or alloy or the entire surface, thereafter implanting ions, and allowing self-alignment. CONSTITUTION:A field oxide film and a gate oxide film are formed on a P type Si substrate, and a gate wiring 4a comprising an Mo film of about 0.3mum is provided. Then, a treatment is performed in a gas of H+N containing 5% H at 600 deg.C, the surface of the Mo4a is nitrided and divided into Mo4b and molybdenum enitride 4c. Then, As ions are implanted as usual, activation is performed in N2, and the source and drain layers 5 are formed. The surface is covered by PSG, and wiring is provided, and the FET is completed. By using the nitride film of Mo, W, or alloy of Mo and W, the thickness which is larger than the theoretically expected thickness is obtained. In this method, the variation in a flat-band voltage or in a threshold voltage is not generated at the time of ion implantation. |
