Electron Transport Characteristics of Wurtzite GaN

Abstract

A three-valley Monte Carlo simulation approach was used to investigate electron transport in wurtzite GaN such as the drift velocity, the drift mobility, the average electron energy, energy relaxation time, and momentum relaxation time at high electric fields. The simulation accounted for polar optical phonon, acoustic phonon, piezoelectric, intervalley scattering, and Ridley charged impurity scattering model. For the steady-state transport, the drift velocity against electric field showed a negative differential resistance of a peak value of 2.9×105 m/s at a critical electric field strength 180×105 V/m. The electron drift velocity relaxes to the saturation value of 1.5×105 m/s at very high electric fields. The electron velocities against time over wide range of electric fields are reported.

Carrier Transport Properties of GAN in High Electric Field

“…For the further increase in the electric field strength beyond 300 kV/cm, the electron drift velocity saturated at 2.00 × 10 7 cm/s. It is noticed that our result is an average to most of the experimental and MC results [10][11][14][15][16][17]. Fig.…”

“…The simulation process repeated to evaluate the drift motion under constant electric field up to 1000 kV/cm and the following scattering process until the maximum flight time was achieved. The transport properties of GaN were reported by several researchers [9][10][11][14][15][16][17][18]. Carrier's drift velocity and average energy during the total simulation time t max were simulated respectively using (3) and…”

“…Their simulation results showed that hole-initiated multiplication dominated in -A direction for electric field above 3.2 MV/cm. Much efforts had been reported in literatures in the investigation of the multiplication gain and excess noise factor of GaN but less attention was paid to the transport properties [11] such as drift velocity, energy and impact ionization coefficient of carriers, in particular of holes in GaN which are the fundamental factors that affect the performance of GaN APDs. Thus in this work, Monte Carlo method is employed to develop a model to simulate the transport properties such as drift velocity, energy, occupancy, ionization rates and ionization coefficients of holes and electrons in GaN under electric field.…”

Research on the origin of negative effect in uniform doping GaN-based Gunn diode under THz frequency

“…Recently, many efforts have been made to improve the efficiency, operating frequency, and output power of Gunn diodes, both in vertical and in planar [3][4][5]. What is more, the electron energy relaxation time in GaN is much smaller than that in traditional III-V materials such as GaAs [6,7]. This has led to the attention into the research of negative differential resistance of GaN for Gunn operation toward THz frequencies [8][9][10][11].…”

Characteristics of AlGaN/GaN HEMTs for Detection of MIG

“…, the electron transport characteristics in Wurtzite blend GaN are compared and contrasted amongst varied Electric fields. It is demonstrated that electron velocity in GaN, in the absence (or very small value) of an applied Electric Field possesses velocities in the range of 0.25 × 10 5 m/s and 1.25 × 10 5 m/s and exhibit an allowable range of energies of ~0.12 eV [35][36]. Therefore, the DC bias can be calculated as: yields V = 6.99436 × 10 −20 .…”