Process integration of Pr-based high-k gate dielectrics
We present the process integration of the Pr-based high-k oxides Pr2O3, PrTixOy and PrxSiyOz for CMOS devices. MOS structures were grown in form of p+ poly-Si/Pr-based dielectric/Si(100) by MBE. RIE with CF4/O2 plasma was used to selectively remove the poly-Si layer. It was found that the Pr-based oxides layers can be dissolved with high selectivity in diluted H2SO4 solutions. Details of the etch kinetics of Pr-based oxides and poly-Si were studied. Electrical characteristics of MOS stacks with integrated PrxSiyOz are presented.
pr2o3 cmos mbe rie pr-silicate wet etching