| 摘要 |
PURPOSE:To perfectly perform the flow treatment of a PSG film and restrain the re-distribution of impurity in an Si substrate to the minimum by a method wherein the heat treatment of the PSG film is performed for a short time at a high temperature by radiation heating system. CONSTITUTION:After a field oxide film 2 and a gate oxide film 3 are formed, and polycrystalline Si films 4 serving as gate electrodes and wirings are formed, N<+> diffused layers 5 serving as the source and drain are formed by self-alignment method. Next, an insulation film of SiO2 as the main body is grown by the reaction of SiH4 with O2, as the layer insulation film between the polycrystalline Si wirings 4. Thereat, it is changed into a PSG film 6 by mixing phosphorus by doping PH3 gas, and thus the surface part thereof is kept liable to flow. Thereafter, the entire body of the Si wafer is heat-treated by infrared ray radiation heating by the heating system with a graphite heater in high vacuum in order to flat the PSG film 6. This heating makes the PSG film 6 flow satisfactorily, and then the re-distribution of impurity of the N<+> diffused layers formed previously which serve as the source and drain is small, and accordingly hardly advances. |
