Improved interface quality and charge-trapping characteristics of MOSFETs with high-κ gate dielectric

The effects of high-pressure annealing on interface properties and charge trapping of nMOSFET with high-κ dielectric were investigated. Comparing with conventional forming gas (H₂/Ar=4%/96%) annealed sample, nMOSFET sample annealed in high-pressure (5-20 atm), pure H₂ ambient at 400°C shows 10%-15% improvements in linear drain current (I_d) and maximum transconductance (g_m,max). Interface trap density and charge trapping properties were characterized with charge pumping measurements and "single pulsed" I_d-V_g measurements where reduced interface state density and improved charge trapping characteristics were observed after high pressure annealing. These results indicate that high pressure pure hydrogen annealing can be a crucial process for future high-κ gate dielectric applications.