Device processing technology for nuclear electronics

For electronics used for instrumentation of reactors and so on, nuclear system appliances, robots for nuclear power, and so forth, required for high reliability, semi-conductor elements stably acting for a long term at severe complex environment under high temperature and high radiation were required. In order to realize this, development on a process technology for element production using new semi-conductor materials alternating to Si must be carried out rapidly. On process technology on radiation resistant bonding, at first, by forming and evaluating a Schottky bonding on hetero-epi film of 3C-SiC/Si, an unfinished good performance of 240 V in reverse direction volt-resistance could be obtained. Then, by evaluating the ATR method as a candidate of the oxidation process observation method through testing various oxide films, this method was confirmed to be an effective method to elucidate interface and quality of the films. At last, crystalline AlN/SiC-MIS had 0.27 V in VFB which was much smaller on comparison with that of SiO2/SiC-MIS, and showed that AlN was a powerful candidate of gate insulation film. On process technology on radiation resistant conductive control, by attempting to carry out C/Ga co-insertion into SiC without any report, it was found that p-type dopant showed no change in activation rate in low dose of C on comparison with no co-insertion of C and showed its reduction by increasing dose of C. And, on evaluation technology on radiation-induced defect, some degree of radiation damage on every devices of Si Schottky diode and buried oxide film structure Si-junction diode SOI by using microbeam were investigated, to confirm this testing method to be effective for evaluation of the radiation-induced defect. (G.K.)