Improvement of buried oxide quality in low-dose SIMOX wafers by high-temperature oxidation

For commercial ULSIs using SOI CMOS, low-dose SIMOX wafers are very attractive because of their excellent crystalline quality and low cost compared with high-dose SIMOX wafers. However, it has been reported that the buried-oxide (BOX) of the low-dose SIMOX wafer has a couple of problems to be solved. One problem is the presence of “pipe” leakage caused by particles shadowing the oxygen ion beam during the implantation. Another problem is the breakdown electric field being lower than that of the thermal oxide. In this paper, it is shown that high-temperature oxidation, which increases the BOX thickness, effectively solves the above problems