Interface characterization of nitrogen plasma-treated gate oxide film formed by RTP technology

Abstract

We described thin nitrogen plasma-treated gate oxide film formed by rapid thermal process technology. This thin nitrogen plasma-treated gate oxide film has been formed using remote plasma nitridation process onto in situ steam generated oxide layer. We investigated the nitrogen profile within the gate dielectric film formed by this technique using SIMS analysis. The result shows that nitrogen concentration profile is composed of high at top surface and low at SiO2/Si interface. The peak concentration of nitrogen is placed at near top place and goes rapidly down to SiO2/Si interface. This nitrogen profile results in excellent boron diffusion barrier characteristics and superior interface properties for p+PMOSFET. We also performed the electrical analysis such as capacitance-voltage (C-V), gate leakage current, dielectric breakdown voltage and time-to-breakdown (TBD) measurement. It has been found that this thin nitrogen plasma-treated gate oxide film results in superior electrical reliability having significant lower leakage current, superior dielectric strength and outstanding TBD.