Comprehensive Understanding of the Mobility Scattering Mechanisms and Evaluation of the Universal Mobility in Ultra-Thin-Body Ge-OI p-and n-MOSFETs

The mobility scattering mechanisms in the ultra-thin-body (UTB) Ge-OI p- and n-MOSFETs have been systematically investigated. It is found that the E-eff(-2) dependence is confirmed for the hole mobility in Ge-OI pMOSFETs, while the electron mobility exhibits an unusually strong dependence on E eff (proportional to E-eff(-4)). The mu (ph) exhibits an E-eff(-0.3) dependence for both holes and electrons, along with a temperature dependence of similar to T-1.8. The mu (total) is measured at different depletion layer carrier densities (N-depl), revealing that mu (Coulomb) increases with the rise of N-depl. Specially, mu (Coulomb) exhibits N-depl(0.5) and N-depl(1.8) dependencies for electrons and holes, respectively. Consequently, more pronounced mobility degradation has been confirmed in UTB Ge-OI nMOSFETs than in UTB Ge-OI pMOSFETs. These findings suggest universal carrier scattering mechanisms for both holes and electrons in UTB Ge-OI channels, which are valuable for understanding carrier transport in thin-channel Ge devices for future advanced technology nodes.