| 摘要 |
PURPOSE:To produce with high reproducibility a metal silicide layer, uniform and stable in nature and small in serial resistance, in the presence of a natural oxide film on a substrate surface by a method wherein ions of a metal, easy to combine with Si to form a metal silicide, are driven into an Si substrate and the substrate is subjected to heat treatment for the metal and Si to react into a metal silicide. CONSTITUTION:This method of forming a metal silicide may be applied, for example, in the formationof a metal for a MOS transistor gate. On a P type Si substrate 21, a field oxide film 22, gate oxide film 23, N<+> type polycyrstalline Si film 24 are formed. Next, ions, of a metal apt to form a metal silicide are driven into the entire surface for the formation of an ion-implanted layer 25. The substrate 21 in its entirety is subjected to heat treatment at temperatures of approximately 400 deg.C for the formation of a metal silicide layer 26 on the N<+> type polycrystalline Si film 24. In this case, with the N<+> type polycrystalline Si film 24 being doped with a high concentration of the impurity metal, no Schottky junction effect is seen between the N<+> type polycrystalline Si film 24 and the metal silicide layer 26. Only an ohmic contact is established there, which greatly reduces the resistance to be presented by the MOS transistor gate. Conventional processes follow for the completion of a MOS transistor. |
