Simulation of Hot-Electron Effects with Multi-band Semiconductor Devices

In this work, we present a 2-Valley energy band model of electron transport that delivers more accurate solutions compared with the Farahmand model but with improved convergence and a faster solution time for very high electric fields. This was achieved by implementing the Fermi-Dirac integral distribution as a substitution for the Boltzmann exponential, electron carrier temperature due to heat generation and conduction in the semiconductor lattice, and additional electron concentration modeling for a second conduction energy band minima. The model was primarily tuned by varying the electron temperature relaxation time constant. It was tested using a GaN-based High Electron Mobility Transistor using the Finite-Element Quasi Fermi method.