Space-charge limited currents in coaxial diodes with electron backscatter

Oliver, B. V. ; Genoni, T. C. ; Rose, D. V. ; Welch, D. R.

[S.l.] : American Institute of Physics (AIP)
Published 2001
ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The effect of backscattered electrons on space-charge limited currents of cylindrical (coaxial) diodes with anode center conductors is studied. The scattered electrons are parametrized by a fractional current density α and fractional energy β of the incident electrons. For bipolar flow, current enhancement factors of 2.5 are calculated for α, β(similar, equals)0.5. Comparison of the model equations to one-dimensional particle-in-cell simulations with fully integrated Monte Carlo scattering algorithms demonstrates very good agreement for a range of energies and anode materials. In the absence of backscattering, the bipolar diode impedance decreases for increasing ratio of cathode to anode radius rc/ra for ratios greater than about 20. © 2001 American Institute of Physics.
Type of Medium:
Electronic Resource
URL: