Nitrogen Effects on the Integrity of Silicon Dioxide Grown on Polycrystalline Silicon

Chao Sung Lai, Chyuan Haur Kao, Chung Len Lee, Tan Fu Lei
2007 Journal of the Electrochemical Society  
In this paper, we describe a simple technique to achieve a thin nitrided polyoxide film, only requiring an extra nitrogen implantation to be compatible with the floating gate nonvolatile memory process. The integrity of polyoxides is improved by using the through-silicon-gate nitrogen implantation. Nitridation can be achieved by implanting nitrogen into polysilicon gate followed by a high temperature annealing to drive the nitrogen atoms across the polysilicon, through the polyoxide, and to
more » ... rporate nitrogen at the polyoxide/polysilicon interface. The nitrogen-rich layer formed during the driven-in process not only strengthens the polyoxide structure but also improves the polyoxide quality. Improvements of electrical characteristics such as a low leakage current, a low electron trapping, and a high breakdown field for both positive and negative biases have been observed.
doi:10.1149/1.2767854 fatcat:onlqgrz3qzbe7c22tqk6egnnhm