Small Signal Response of Inversion Layers in High Mobility In0.53Ga0.47As MOSFETs Made with Thin High- Dielectrics

Ultra-high mobility compound semiconductor-based MOSFETs and quantum-well FETs could enable the next generation of logic transistors operating at low supply voltages since these materials exhibit excellent electron transport properties. While the long channel In0.53Ga0.47As MOSFET characteristics exhibit promising characteristics with unpinned Fermi level at the InGaAs-dielectric interface, the high field channel mobility as well as sub-threshold characteristics needs further improvement. There could be contribution from one or several potential scattering processes to cause mobility degradation in surface channel In0.53Ga0.47As MOSFETs such as interface roughness, remote or local optical phonon scattering and remote Coulomb scattering due to charges in the gate oxide. In this work, we present a comprehensive equivalent circuit model that accurately models the experimental small signal response of inversion layers in In0.53Ga0.47As MOSFETs fabricated with LaAlO3 gate dielectric and enables accurate extraction of effective channel mobility. Temperature dependent measurements allow us to identity the various scattering mechanisms.