Effects of deuterium anneal on MOSFETs with HfO2 gate dielectrics

The effects of high-temperature (600/spl deg/C) anneal in a dilute deuterium (N/sub 2/ : D/sub 2/= 96 : 4) atmosphere was first investigated and evaluated in comparison to high-temperature forming gas (N/sub 2/ : H/sub 2/= 96 : 4) anneal (600/spl deg/C) and nonanneal samples. The high-temperature deuterium anneal was as effective as the forming gas anneal in improving MOSCAP and MOSFET characteristics such as the C-V curve, drain current, subthreshold swing, and carrier mobility. These can be attributed to the improved interface quality by D/sub 2/ atoms. However, unlike the forming gas anneal, the deuterium anneal provided the hafnium oxide (HfO/sub 2/) gate dielectric MOSFET with better reliability characteristics such as threshold voltage (V/sub T/) stability under high voltage stress.