Development of Self-Consistent NEGF-Poisson Quantum Transport Simulator and Application in Nanoscale Devices

• Main Authors: Han-Wei Hsiao, 蕭翰為
• Other Authors: Yuh-Renn Wu
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/92a2h4

碩士 === 國立臺灣大學 === 光電工程學研究所 === 106 === As the gate length of metal-oxide-semiconductor-field-effect transistors has been scaled down into the sub-10 nm regime, semi-classical Boltzmann transport theory can no longer accurately describe the behavior of electronic transport, since the quantum mechanical effects start to play a dominant role. Non-equilibrium Green''s function formalism is a fully quantum mechanical approach which can take the wave nature of electrons into account, and it provides a framework for describing the incoherent and dissipative transport processes. In this work, we have successfully developed a three-dimensional quantum transport simulator based on solving the NEGF equation and Poisson equation self-consistently to investigate the characteristics of nanoscale devices in the presence of electron-phonon scattering, ionized impurity scattering, and surface roughness scattering. Our modeling can capture the phenomena of current spectrum broadening due to inelastic transition processes and the primary scattering mechanisms of current degradation. According to the self-consistent solutions obtained from the NEGF-Poisson cycle, we can simulate not only the typical electrical properties of output characteristic, such as threshold voltage, ohmic region, and saturation region but also the leakage current from source-to-drain tunneling. In addition, the results are also compared with the traditional drift-diffusion model.