Comprehensive Study on Trap-Induced Bias Instability via High-Pressure D2 and N2 Annealing

Forming gas annealing (FGA) in a deuterium (D2) ambient is crucial importance to MOSFET fabrication technologies related to alleviation of trap state at Si/SiO2 interface as well as oxide bulk by
$D_{2}$
passivation. In this study, post-metal annealing (PMA) process with
$D_{2}$
and
$N_{2}$
gases under a high-pressure condition was conducted to verify performance enhancement in gate-enclosed FETs. We explored the trap behaviors inside the bandgap of Si and
$SiO_{2}$
by quantitatively using capacitance-voltage (
${C}$
–
${V}$
) characteristics. Furthermore, the change of deuterium and nitrogen ions in Si/SiO2 gate stack before and after the PMA process was directly investigated by time-of-flight secondary ion mass spectroscopy (ToF-SIMS) depthprofiling technique.