Minority Electron Transport Research Articles

Effect of Heavy Doping on Band Gap and Minority Carrier Transport of AlGaAs/GaAs HBT's

Band gap narrowing in heavily doped p-type GaAs is estimated by photoluminescence measurement. Measured values agree well with the theoretical results. Monte Carlo simulation of minority electron transport demonstrates that plasmon scattering plays an essential role in heavily doped p-type GaAs. Theoretical calculations, including these heavy doping effects, on heterojunction bipolar transistors (HBT's) show that maximum oscillatiorn frequency of over 300 GHz is expected by increasing the hole concentration of the base layer to 1×1021 cm-3.

The role of the split-off band in electron-hole energy exchange dynamics in selected III-V semiconductors

We report a Monte-Carlo investigation of Coulomb electron-hole scattering processes involving the split-off band in selected III-V semiconductors in the context of steady-state high-field minority-electron transport. Due to the small value of the relevant hole overlap factors, as well as the relative values of the Γ-L energy separation and the split-off energy, such processes do not make a significant contribution to the minority electron energy loss rate in In0.53Ga0.47As. In InP, however, the ΓhΓs process accounts for a significant fraction of the total Γ-electron energy loss to holes.

A Monte Carlo study of electron-hole scattering and steady-state minority-electron transport in GaAs

We report the first bipolar Monte Carlo calculations of steady-state minority-electron transport in room-temperature p-GaAs including multiband electron-hole scattering with and without hole overlap factors. Our results show how such processes, which make a significant contribution to the minority-electron energy loss rate, can affect steady-state minority-electron transport. Furthermore, we discuss several other issues which we believe should be investigated before present Monte Carlo treatments of electron-hole scattering can provide quantitative information.

Monte Carlo investigation of minority electron transport in In 0.53Ga 0.47As

The transport of minority electrons in p-type In 0.53Ga 0.47As has been investigated for doping levels of 10 17 and 5×10 17 cm −3. It is found that the electrons exhibit smaller velocities at electric fields below 4 kV/cm when the electron-hole interaction is taken into account. The velocities at fields above 4 kV/cm are higher and reach a maximum at 5 kV/cm. The fraction of electrons that transfer to the upper valleys are significantly reduced for electric fields below 6 kV/cm.

Monte Carlo investigation of minority-electron transport in In0.53Ga0.47As

The transport of minority electrons in p-type In0.53Ga0.47As has been investigated for 1017 and 5×1017 cm−3 doping levels. Using Monte Carlo methods and including inelastic electron-hole (e-h) scattering, it is found that the mean electron velocity for fields below 4 kV/cm is smaller when e-h scattering is included than when it is absent. The mean velocities above 4 kV/cm are higher when e-h scattering is included and reach a peak at 5 kV/cm. The study reveals that the principal contribution of the e-h scattering is a more efficient channel of electron energy relaxation, with the consequence of a significantly reduced transfer of carriers to the upper valleys for fields below 6 kV/cm.

Resonant tunneling spectroscopy of hot minority electrons injected in gallium arsenide quantum wells

We have employed a new electron spectroscopy technique based on resonant tunneling to study hot minority-electron transport in GaAs quantum wells, following ballistic injection. Direct information on the momentum and energy distribution perpendicular to the heterointerfaces is obtained from the measured resonant tunneling current without requiring derivative techniques. For injection energies of ≂0.2 eV, strong energy and momentum relaxation occurs over distances≲250 Å making impossible the observation of minority-electron ballistic transport in heavily doped (>1018 cm−3) GaAs. The energy distribution is found to be strongly non-Maxwellian; from our data we can infer electron scattering times ≤10−14 which are consistent with recent evidence of strong electron-hole scattering in GaAs quantum wells.