Effects of High‐Pressure H₂ and D₂ Post‐Metallization Annealing on the Electrical Properties of HfO₂/Si_0.7Ge_0.3

Abstract

High‐pressure annealing (HPA) in both hydrogen (H2) and deuterium (D2) environments is attempted on HfO2/Si0.7Ge0.3 capacitors as a post‐metallization annealing (PMA) approach. As compared with conventional forming gas annealing (FGA), a dramatic reduction in the interface state density (Dit) is achieved after both H2‐ and D2‐HPA processes at the equivalent temperature (300 °C) and time (30 min) by effectively passivating the Ge‐induced dangling bonds at the interface region. Meanwhile, the stress‐induced leakage current characteristics are only improved by the D2‐HPA process, indicating that D‐passivation is more resistant to external electrical stress than H‐passivation. As the PMA temperature increases to 500 °C, both HPA further decreases the Dit, but a significant increase is observed for FGA. In addition, the PMA temperature‐dependent degradation of leakage current is less in HPA than in FGA.

Effect of high temperature annealing on cryogenic transport properties of silicon MOSFETs with a thin SiO2/HfO2 stacked dielectric

“…It is worth mentioning that many studies have reported the effect of forming gas annealing (FGA) on transistor mobility enhancement [38][39][40]. An annealing atmosphere with deuterium (D 2 ) instead of hydrogen (H 2 ) can increase the mobility of hafnium-based MOSFETs to near 400 cm 2 /(V•s) at room temperature [41,42], but there is still much room for improvement. Therefore, it is important to investigate the effect of post-deposition annealing (PDA) temperature on the cryogenic transport properties of thin-layer hafnium-based MOSFETs in order to further enhance the mobility.…”