Accession Number:

ADA158832

Title:

30 MeV Electron Beam Irradiation Effects on GaAs(1-x)P(x) LEDs (Light Emitting Diodes).

Descriptive Note:

Master's thesis,

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

1985-06-01

Pagination or Media Count:

98.0

Abstract:

LEDs of the ternary alloy GaAs.7P.3, were irradiated with a 30 MeV electron beam. The effects this exposure had on peak wavelength, absolute and relative light output intensities, and current-forward bias characteristics were studied. A simple model of LED current controlling mechanisms is described and a mathematical approach for deriving a descriptive damage-constant is provided. Observed irradiation effects consisted of increased current and decreased light output intensity for a given forward bias voltage and indicate that the devices tested are an order of magnitude softer to electron radiation than results previously reported. Damage constants were calculated group 9 2.9 x 10 to the -14th power sq cme, group A5 2.6 x 10 to the -14th power sq cme, and group 3 1.4 x 10 to the -14th power sq cme. Shielded and un-shielded devices were compared to determine if the secondary electron production for Bremsstrahlung losses would reduce the total fluence required for degradation. The results of this experiment were inconclusive. A procedure was developed to determine the electron beam current density for use in dose estimations. Electron doses were a factor of three higher when compared to the previous method of calculation. Keywords include LEDs, GaAS1-xPx, electron beam, Bremsstrahlung losses, electroluminescence, and damage constant.

Subject Categories:

  • Electrooptical and Optoelectronic Devices
  • Particle Accelerators

Distribution Statement:

APPROVED FOR PUBLIC RELEASE