Enhanced anneal behaviour of boron implanted silicon

In an attempt to prevent contamination from the furnace and the formation of nitrides in boron implanted silicon wafers annealed in dry nitrogen at 11000C a barrier layer of deposited SiO2 was deposited on the wafer prior to the anneal. The results presented indicate that in the presence of a silox layer, the effects due to contamination and formation of nitrides must be small as the junction characteristics are good. It also appears that the apparent enhancement in the annealing rate of an implanted wafer due to the presence of the silox layer has contributed greatly to improved junction characteristics by removing implant damage. It is suggested that silox could act as a sink for surface defects. (U.K.)