Effects of high-temperature forming gas anneal on HfO/sub 2/ MOSFET performance

Effects of forming gas (FG) annealing on HfO/sub 2/ MOSFET performance have been studied. High-temperature (500-600/spl deg/C) FG annealing has been shown to significantly improve carrier mobility and subthreshold slopes for both N and PMOSFETs. The improvement has been correlated to the reduction in interfacial state density. The effectiveness of FG annealing has also been examined on samples that underwent surface preparations with NH/sub 3/ or NO annealing prior to HfO/sub 2/ deposition. It was found that FG annealing did not degrade PMOS negative bias temperature instability characteristics.