| 摘要 |
PURPOSE:To prevent the isolation characteristics of a semiconductor device from deteriorating due to radiation by a method wherein the insulating films of the isolated grooves are formed of SiO2 and SiN, or SiO2, SiN and SiO2, or SiO2 and PSG. CONSTITUTION:Interelement insulated grooves 17 are formed, and after that, firstly, the grooves 17 are covered with a 10-50nm thick SiO2 film 18 by a thermal oxidation method, by which the best interfacial characteristics can be obtained. Then, insulating films 19 in the isolated grooves 17 are formed in a constitution of an SiO2 film and an SiN film, or of an SiO2 film, an SiN film and an SiO2 film, or of an SiO2 film and a PSG film using the 20-200nm thick SiN film or the PSG film containing a phosphorus concentration of 2-10mol% and the grooves are insulatingly isolated. According to this constitution, the holes of the electron-hole pairs to generate in the SiO2 film due to a radiation irradiation are captured by the electron capture center in the SiN film or the PSG film, no interfacial level is generated on the interface between the SiN film and the SiO2 film and a reduction in the threshold value, an augmentation in leakage and so forth are prevented. As a result, the radiation- resistant efficiency of the semiconductor device is made to improve. |
