Effects of high temperature forming gas anneal on the characteristics of metal-oxide-semiconductor field-effect transistor with HfO2 gate stack

Abstract

The effects of high temperature forming gas (N2:H2=96:4) anneal (600 °C) prior to metallization have been evaluated in terms of the improvement in the carrier mobility of HfO2/nitride layer gate stack metal-oxide-semiconductor field-effect transistors with TaN gate electrode. The high-temperature forming gas anneal has been found to be effective in improving the interface quality by lowering both interface state density and interface charges. The improvements resulting in decreased Coulombic scattering centers can be attributed to hydrogen atoms that were concentrated near the interface.