Electronic transport studies of bulk zincblende and wurtzite phases of GaN based on an ensemble Monte Carlo calculation including a full zone band structure

Abstract

The ensemble Monte Carlo technique including the details of the first four conduction bands within the full Brillouin zone is used to calculate the basic electronic transport properties for both zincblende and wurtzite crystal phases of bulk gallium nitride. The band structure throughout the Brillouin zone is determined using the empirical pseudopotential method. Calculations of the electron steady-state drift velocity, average energy, valley occupancy and band occupancy in the range of electric fields up to 500 kV/cm are presented. It is found that the threshold electric field for intervalley transfer is greater and that the second conduction band is more readily occupied in wurtzite than in zincblende GaN over the range of electric fields examined here.

Modeling and simulation of bulk gallium nitride power semiconductor devices

“…∆E A,0 however show a significant spread and ranges between 140 meV -245 meV. 41,43,67 Simulations performed using ∆E A,0 = 240 meV gives an effective Mg doping density of around 5.2x10 17 cm −3 for an initial doping of 1x10 19 cm −3 which concurs with the experimental data 4 and is used in our work. The value of α n and α p is 3.4x10 −6 meV-cm for Si-doped 39 and 3.14 x10 −5 meV.…”

“…The forward conduction and reverse breakdown simulations are performed for PN diodes with active area of 0.11 mm 2 (3.7 kV) and 0.72 mm 2 (2.6 kV) respectively. The 3.7 kV device has a 40 µm n-drift layer with a doping concentration of 6x10 15 cm −3 , a thin 0.5 µm n+ cathode region with a doping concentration of 1x10 19 cm −3 and a 1.5µm thick p+ layer with an effective doping of 5.2x10 17 cm −3 . The 2.6 kV device has a 15 µm thick n-drift layer with a doping concentration of 2x10 16 cm −3 , a 0.5 µm n+ cathode region with a doping concentration of 1x10 19 cm −3 and a 1.5 µm thick p+ layer with an effective doping of 5.2x10 17 cm −3 .…”

“…The 3.7 kV device has a 40 µm n-drift layer with a doping concentration of 6x10 15 cm −3 , a thin 0.5 µm n+ cathode region with a doping concentration of 1x10 19 cm −3 and a 1.5µm thick p+ layer with an effective doping of 5.2x10 17 cm −3 . The 2.6 kV device has a 15 µm thick n-drift layer with a doping concentration of 2x10 16 cm −3 , a 0.5 µm n+ cathode region with a doping concentration of 1x10 19 cm −3 and a 1.5 µm thick p+ layer with an effective doping of 5.2x10 17 cm −3 . The choice of a thicker device for forward simulations helps to minimize the contribution of parasitic and contact resistances when compared to the bulk resistance contribution from the thick n-drift layer.…”

“…Different Monte Carlo calculation methods like the full potential linearized augmented plane wave (FLAPW), 12 orthogonalized linear combination of atomic orbitals (OLCAO) 13 or the empirical pseudo potential method (EPM) 14 are used to determine the band structure and hole and electron effective masses. 12,[14][15][16][17] Similar Monte Carlo calculations are performed to determine the bulk electron [18][19][20][21][22][23][24][25][26][27] and hole [28][29][30][31] mobility employing different band structure and scattering mechanisms. Although experimentally determined values of electron mobility [32][33][34][35] are reported there are few available experimental data for hole mobility.…”

Overshoot effects of electron on efficiency droop in InGaN/GaN MQW light-emitting diodes

“…Our model explains this behavior. At low temperatures, the impact of temperature on the band offset is dominant, 26 and increasing temperature leads to low φ EBL ; at high temperatures, the scattering time becomes shorter and the strong scattering hinders ballistic transport. 24 Recently, an anomalous temperature-dependence of electroluminescence intensity in GaN-based LEDs was reported.…”