Accession Number : AD0728306

Title :   Temperature Dependence of D.C. and Pulsed Electroluminescence in Anthracene Crystals,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO)

Personal Author(s) : Williams,D. F. ; Schadt,M.

Report Date : 1969

Pagination or Media Count : 8

Abstract : An efficient solid electron injecting contact has been developed for anthracene, capable of sustaining very high electron currents about 0.01 amp/sq cm. With this electrode, hole injection occurs with most materials normally used as a second contact, and electron-hole recombination radiation appears. The spectral distribution of the electroluminescence is independent of the second electrode material, though differences in the time dependence of both the current and the light emission on applying a step voltage are observed. At room temperatures the spectra from optical or electrical excitation are equivalent, but at lower temperatures spectral differences appear for some types of anthracene crystal. Thus a significant spectral tail is observed in the low temperature (100K) electroluminescence of crystals grown from the melt under argon, but not if grown under helium. This is also shown in the different current and temperature dependence of the intensity of the major vibrational progression of the emission. Included argon probably causes the formation of recombination centres, which are different from the defects observed in low temperature (4K) fluorescence experiments for all melt grown crystals. Solution grown flakes, sublimation flakes and powdered anthracene also show electroluminescence spectra which differ in some degree from optically excited spectra. (Author)

Descriptors :   (*ANTHRACENES, *ELECTROLUMINESCENCE), PHOTOCONDUCTIVITY, CRYSTAL GROWTH, FLUORESCENCE, CANADA

Subject Categories : Electricity and Magnetism
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE