| 摘要 |
PURPOSE:To protect poly-silicon in a flow treatment process by a method wherein a second poly-silicon is plasma-nitrided so as to be coated with a nitride film. CONSTITUTION:A first poly-silicon gate 2 is built on a silicon substrate 1, an interlaminar insulating film 3 is grown, a second poly-silicon 4 is constructed through a CVD method under the reduced pressure, and As<+> and P<+> ions are implanted into the poly-silicon 4. Next, the second poly-silicon 4 is selectively etched through photolithography and plasma-nitrided in NH3 gas for the formation of a nitride film 10, when a DC bias applied to the substrate 1. Next, an oxide 5 is grown, an impurity doped oxide film 6 for the flow is grown and then treated in an atmosphere of H2/O2=1/6 at temperature of 900 deg.C, and a glass flow is performed. Lastly, a contact window 7 is opened and an Al wiring 8 is selectively formed. By these processes, poly-silicon is prevented from oxidizing in a flow treatment process. |
