| 摘要 |
PURPOSE:To prevent the generation of the irradiation loss of a gate oxide film and contrive the reduction of the wiring resistance, by constituting a gate electrode of a semiconductor film wherein the impurity is added in low density and another one wherein the impurity is added in high density. CONSTITUTION:An SiO2 film 2 is deposited on an Si substrate 1, only on the region serving as an element part 3, the film 2 is removed, accordingly the substrate 1 is exposed. Next, a gate oxide film 4 is grown on the surface of the exposed substrate 1. Next, a polycrystalline Si 5 wherein the impurity is not added is deposited over the entire surface of the substrate 1. Next, a polycrystalline Si 6 wherein the impurity is added is deposited on the Si 5. The polycrystalline Si is left only on the region constituting a gate part and a wiring part. Impurity ions are implanted resulting in the formation of source.drain parts 7, 8. In such a gate electrode structure, the amount of impurity introduced into the film 4 can be kept to the minimum. It can greatly reduce structural defects in the film 4. Besides, when using a polycrystalline Si as the wiring by the Si 6, the wiring resistance can be reduced. |
