The effects of Fluorine implantation and ex-situ Nitrogen anneal on Reliability improvement of 5V CMOSFETs

The effect of Fluorine implantation after gate poly deposition and ex-situ Nitrogen anneal after thin gate oxide formation on Time-Dependent Dielectric Breakdown (TDDB) and Negative-Bias Temperature Instability (NBTI) improvement were studied in 0.13um Dual Gate Oxide CMOS Technology for 5V CMOSFETs. The TDDB lifetime was increased by about 1 order for 5V n/p-MOSFET by Fluorine implantation. The 5V p-MOSFET NBTI lifetime is increased an order of magnitude by Fluorine implantation and the ex-situ Nitrogen anneal. A reduction in the Flicker noise and interface trap density was observed for the group with Fluorine implantation and Ex-situ Nitrogen anneal followed by Fluorine implantation. This result demonstrates that optimization of Fluorine and Nitrogen within the gate oxide is necessary for reliability improvement of 5V CMOSFETs in 0.13um technology