TY - GEN
T1 - High field transport in GaN and AlGaN/GaN heterojunctions
AU - Yamakawa, Shinya
AU - Saraniti, Marco
AU - Goodnick, Stephen
PY - 2007
Y1 - 2007
N2 - Here we report on high field transport in GaN and GaN field effect devices, based on the rigid-ion model of the electron-phonon interaction within the Cellular Monte Carlo (CMC) approach. Using the rigid pseudo-ion method for the hexagonal wurzite structure, the anisotropic deformation potentials are derived from the electronic structure, the atomic pseudopotential, and the full phonon dispersion and eigenvectors for both acoustic and optical modes. Piezoelectric as well as anisotropic polar optical phonon scattering is accounted for as well. In terms of high field transport, the peak velocity is primarily determined by deformation potential scattering described through the rigid pseudo-ion model. The calculated velocity is compared with experimental data from pulsed I-V measurements. We simulate the effects of non-equilibrium hot phonons on the energy relaxation as well, using a detailed balance between emission and absorption during the simulation, and an anharmonic decay of LO phonons to acoustic phonons, as reported previously. Non-equilibrium phonons are shown to result in a significant degradation of the velocity field characteristics for high carrier densities, such as those encountered at the AlGaN/GaN interface due to polarization effects.
AB - Here we report on high field transport in GaN and GaN field effect devices, based on the rigid-ion model of the electron-phonon interaction within the Cellular Monte Carlo (CMC) approach. Using the rigid pseudo-ion method for the hexagonal wurzite structure, the anisotropic deformation potentials are derived from the electronic structure, the atomic pseudopotential, and the full phonon dispersion and eigenvectors for both acoustic and optical modes. Piezoelectric as well as anisotropic polar optical phonon scattering is accounted for as well. In terms of high field transport, the peak velocity is primarily determined by deformation potential scattering described through the rigid pseudo-ion model. The calculated velocity is compared with experimental data from pulsed I-V measurements. We simulate the effects of non-equilibrium hot phonons on the energy relaxation as well, using a detailed balance between emission and absorption during the simulation, and an anharmonic decay of LO phonons to acoustic phonons, as reported previously. Non-equilibrium phonons are shown to result in a significant degradation of the velocity field characteristics for high carrier densities, such as those encountered at the AlGaN/GaN interface due to polarization effects.
KW - GaN
KW - Hot phonons
KW - Monte Carlo simulation
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U2 - 10.1117/12.705272
DO - 10.1117/12.705272
M3 - Conference contribution
AN - SCOPUS:34248657985
SN - 0819465844
SN - 9780819465849
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Ultrafast Phenomena in Semiconductors and Nanostructure Materials XI and Semiconductor Photodetectors IV
T2 - Ultrafast Phenomena in Semiconductors and Nanostructure Materials XI and Semiconductor Photodetectors IV
Y2 - 22 January 2007 through 24 January 2007
ER -