The applications of the high-pressure oxidation process to the fabrication of MOS LSI

The applications of the high-pressure oxidation method to the fabrication of MOS LSI are described. High-pressure selective oxidation of silicon with the use of silicon nitride film as a mask was investigated. Oxidation-induced stacking faults were found to be reduced significantly by the high-pressure steam oxidation compared with the conventional wet O2atmospheric oxidation. The refresh time characteristics in a 16 384-bit MOS dynamic RAM were improved by using the high-pressure oxidation method. Furthermore, a simpler process to grow simultaneously thin- and thick-oxide layers used for the transistors in the MOS RAM with double polysilicon structure was provided.