Conference Paper

Compatibility of dual metal gate electrodes with high-k dielectrics for CMOS

Dept. of Electr. & Comput. Eng., North Carolina State Univ., Raleigh, NC, USA
DOI: 10.1109/IEDM.2003.1269290 Conference: Electron Devices Meeting, 2003. IEDM '03 Technical Digest. IEEE International
Source: IEEE Xplore

ABSTRACT Dual metal electrodes such as Ru, Ru-Ta alloy, TaN and TaSiN were investigated on low EOT single layer HfO2 and stacked HfO2/SiO2 gate dielectrics. It was found that the work function values of metal gates on HfO2 and on SiO2 are similar. Thermal anneal studies of selected metals on the above dielectrics were also performed to evaluate the change in EOT and VFB values.

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