Effects of tungsten polycide process and post-polyoxidation rapid thermal process on electrical characteristics of thin polysilicon oxide

The effects of the tungsten polycide technologies and rapid thermal anneali ng (RTA) on thin polyoxide electrical characteristics have been investigate d. It is found that a thin polyoxide with dichlorosilane (DCS)-based chemic al vapor deposition (CVD) WSiX exhibits both good J-E characteristics and r eliability. This is due to moderated fluorine incorporation, which improves poly-Si/SiO2 interfaces region but not degrades the bulk polyoxide. Moreov er, the post-polyoxidation RTA is also found to improve the polyoxide quali ty. According to the results, the DCS-based CVD WSiX with post-polyoxidatio n RTA is a good candidate for polycide gate technique in high-density nonvo latile memories.