Transient and Steady-state Electron Transport Properties in Bulk Doped Ternary Nitride Materials Using an Ensemble Monte Carlo Method

An ensemble Monte Carlo simulation is used to compare transient and steady-state electron transport in Ga0.2In0.8N, Al0.2Ga0.8N and Al0.2In0.8N materials. Three valleys model at the ?, U and K are represented by non-parabolic ellipsoidal shaps centered on important symmetry points of the Brillouin zone. For all materials, it is found that electron velocity overshoot only occurs when the electric field is increased to a value above a certain critical field, unique to each material. This critical field is strongly dependent on the material parameters. Transient velocity overshoot has also been simulated, with the sudden application of fields up to ?5×107 Vm-1, appropriate to the gate-drain fields expected within an operational field effect transistor. The electron drift velocity relaxes to the saturation value of ?1.35×105ms -1 within 3 ps, for all materials.