High Field Carrier Transport Properties of Al0.45Ga0.55N


  • Wesley Ooi Tat Lung Multimedia University
  • Cheang Pei Ling
  • You Ah Heng
  • Chan Yee Kit




Aluminium Gallium Nitride (AlGaN), avalanche photodiode, transport properties, impact ionization


This work presented Monte Carlo (MC) simulation of Al0.45Ga0.55N to investigate the carrier transport properties in the high electric field region including impact ionization. The simulation investigates both electron and hole considering two non-parabolic conduction band and valence band respectively. The carriers’ drift velocity, energy and occupancy are simulated with respect to electric field at room temperature. The electron drift velocity peak at 2.70 × 107 cm/s with the electric field of 240 kV/cm. The electron starts to excite to higher valley at 170 kV/cm and has a spike in energy at 700 kV/cm due to the occurrence of impact ionization. The impact ionization rates are computed using modified Keldysh equation and it is shown that hole impact ionization rate is higher than that of electron for Al0.45Ga0.55N. This work also presents the impact ionization coefficient with hole dominating the impact ionization process above the electric field of 2.6 MV/cm.

Author Biography

Wesley Ooi Tat Lung, Multimedia University

Master Student


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