Process-induced damage-a study of hydrogen and deuterium passivation

A comparative study of the anneal efficiencies of deuterium (D₂) and hydrogen (H₂) in passivating the interface defects for plasma damaged MOSFETs has been conducted. Experimental results reveals that D₂ annealed devices show enhanced passivation of interface states (D_it), with a decrease in charge pumping current of 15% less than H₂ annealed devices. These devices also show higher transconductance (G_m) improvements and better threshold voltage (V_t) recovery, with increased hot carrier resistance compared to the H₂ annealed ones. Temperature based anneals indicate that while D_it and G_m improve with increasing temperature, V_t recovery is independent of it, indicating that the threshold voltage shifts are possibly due to oxide charge. The interface traps in the plasma-damaged device have been monitored using random telegraph signals (RTS), 1/f noise and charge pumping (CP)