CMOS integration of epitaxial Gd2O3 high-k gate dielectrics

Epitaxial gadolinium oxide (Gd2O3) high-k dielectrics are investigated with respect to their CMOS compatibility in metal oxide semiconductor (MOS) capacitors and field effect transistors (MOSFETs). MOS capacitors with various gate electrodes are exposed to typical CMOS process steps and evaluated with capacitance voltage (CV) and current voltage (JV) measurements. The effects of high temperature processes on thermal stabilities of channel/dielectric and dielectric/gate electrode interfaces is studied in detail. A feasible CMOS process with epitaxial gate oxides and metal gate electrodes is identified and demonstrated by a fully functional n-MOSFET for the first time.