Novel methods to incorporate deuterium in the MOS structures

The deuterium concentration as high as 2/spl times/10/sup 20/ cm/sup -3/ can be incorporated in rapid thermal oxide layers by a process of deuterium prebake and deuterium post oxidation anneal. The deuterium distributed not only at Si/oxide interface but also in the bulk oxide. The deuterium incorporation shows the improvement on soft breakdown characteristics and the interface state density at SiO/sub 2//Si after stress. The addition of very high vacuum prebake process yields a deuterium concentration of 9/spl times/ 10/sup 20/ cm/sup -3/, but also leads to the formation of rough oxide.