Accurate measurements and degradation mechanisms of the channel mobility for MOSFETs with HfO2 as the gate dielectric have been systematically studied in this paper. The error in mobility extraction caused by a high density of interface traps for a MOSFET with high-k gate dielectric has been analyzed, and a new method to correct this error has been proposed. Other sources of error in mobility extraction, including channel resistance, gate leakage current, and contact resistance for a MOSFET with ultrathin high-k dielectric have also been investigated and reported in this paper. Based on the accurately measured channel mobility, we have analyzed the degradation mechanisms of channel mobility for a MOSFET with HfO2 as the gate dielectric. The mobility degradation due to Coulomb scatting arising from interface trapped charges, and that due to remote soft optical phonon scattering are discussed.
- High-k dielectrics
- Mobility degradation
- Mobility measurement
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering