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Full-Text Articles in Electrical and Computer Engineering
On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, Shin'ichi Tanaka
On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, Shin'ichi Tanaka
Department of Electrical and Computer Engineering Faculty Publications
A simple one-speed solution to the Boltzmann equation is used to evaluate the mobility and diffusion coefficient for carriers in forward-biased semiconductor barriers. The analysis shows that although the average kinetic energy of carriers remains near thermal equilibrium, the mobility and diffusion coefficient are strongly reduced by the built-in field. Conventional macroscopic transport equations, which treat the carrier mobility and diffusion coefficient as single valued functions of the kinetic energy will improperly treat transport in forward-biased barriers. The results are important for the careful analysis of metal–semiconductor and heterojunction diodes.
On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, S. I. Tanaka
On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, S. I. Tanaka
Department of Electrical and Computer Engineering Faculty Publications
A simple one-speed solution to the Boltzmann equation is used to evaluate the mobility and diffusion coefficient for carriers in forward-biased semiconductor barriers. The analysis shows that although the average kinetic energy of carriers remains near thermal equilibrium, the mobility and diffusion coefficient are strongly reduced by the built-in field. Conventional macroscopic transport equations, which treat the carrier mobility and diffusion coefficient as single valued functions of the kinetic energy will improperly treat transport in forward-biased barriers. The results are important for the careful analysis of metal-semiconductor and heterojunction diodes.© 1995 American Institute of Physics.
Very Low Resistance Nonalloyed Ohmic Contacts Using Low-Temperature Molecular Beam Epitaxy Of Gaas, M. P. Patkar, T. P. Chin, J. M. Woodall, Mark S. Lundstrom, Michael R. Melloch
Very Low Resistance Nonalloyed Ohmic Contacts Using Low-Temperature Molecular Beam Epitaxy Of Gaas, M. P. Patkar, T. P. Chin, J. M. Woodall, Mark S. Lundstrom, Michael R. Melloch
Department of Electrical and Computer Engineering Faculty Publications
Ex situ nonalloyed ohmic contacts were made to n- and p‐type GaAs using low‐temperature molecular beam epitaxy. For n‐type GaAs, Ag, and Ti/Au nonalloyed contacts displayed specific contact resistitivities of mid 10-7 ohm cm2. For p‐type GaAs, nonalloyed Ti/Au contacts with specific contact resistivities of about 10-7 ohm cm2 were obtained.
Transition Matrix Approach For Monte Carlo Simulation Of Coupled Electron/Phonon/Photon Dynamics, Muhammad A. Alam, Mark S. Lundstrom
Transition Matrix Approach For Monte Carlo Simulation Of Coupled Electron/Phonon/Photon Dynamics, Muhammad A. Alam, Mark S. Lundstrom
Department of Electrical and Computer Engineering Faculty Publications
A new approach for simulating the dynamics of electrons, phonons, and photons is described. The technique provides a Monte Carlo simulation of particle dynamics without the statistical noise associated with direct Monte Carlo simulation, treats physical phenomena with a wide range of time scales, and has a good computational efficiency. A transition matrix is first precomputed by direct Monte Carlo simulation. Particle populations are then updated at regular time steps by simple matrix multiplication while correcting for nonlinear effects such as carrier–carrier scattering, band filling, hot phonons, etc. The technique is well suited to studies of quantum well laser devices …
Characterization Of Photon Recycling In Thin Crystalline Gaas Light Emitting Diodes, M. P. Patkar, M. S. Lundstrom, Michael R. Melloch
Characterization Of Photon Recycling In Thin Crystalline Gaas Light Emitting Diodes, M. P. Patkar, M. S. Lundstrom, Michael R. Melloch
Department of Electrical and Computer Engineering Faculty Publications
Gallium arsenide light emitting diodes (LEDs) were fabricated using molecular beam epitaxial films on GaAs substrates and removed by epitaxial lift-off (ELO). Lifted off devices were then mounted on a Si wafer using a Pd/Au/Cr contact layer, which also served as a back surface reflector. Devices were characterized by electrical and optical measurements, and the results for devices on the GaAs substrate were compared to those for EL0 devices. EL0 LEDs coated with a ZnS/MgF2 antireflection coating exhibited an optical output that was up to six times that of LEDs on GaAs substrates. At the same time, the measured current-voltage …
Temperature Dependence Of Minority And Majority Carrier Mobilities In Degenerately Doped Gaas, Michael L. Lovejoy, Michael R. Melloch, Mark S. Lundstrom
Temperature Dependence Of Minority And Majority Carrier Mobilities In Degenerately Doped Gaas, Michael L. Lovejoy, Michael R. Melloch, Mark S. Lundstrom
Department of Electrical and Computer Engineering Faculty Publications
Measured minority and majority carrier mobility temperature dependencies in heavily doped n- and p-GaAs are compared. Majority carrier mobilities in heavily doped GaAs are essentially temperature ~T! independent while minority carrier mobilities exhibit a roughly 1/T dependence. Majority carrier freezeout, which reduces both majority–minority carrier and ionized impurity scattering, is shown not to be responsible for the 1/T minority carrier mobility dependence. The difference in minority and majority carrier mobility T dependencies is explained in terms of the increased degree of degeneracy of majority carriers with decreased temperature, which decreases majority–minority carrier scattering.