Pulsed KrF laser annealing of RF sputtered ZnS:Mn thin films

Pulsed KrF laser annealing (PLA) of ZnS:Mn thin (800 nm) film phosphors has been investigated as an alternative to thermal annealing for the fabrication of electroluminescent devices. The influence of the surrounding gas pressure during exposure, the energy density (Ed) of the laser beam and the effect of double irradiation is reported. Luminescent properties as function of laser energy density (Ed) are determined via photoluminescent (PL) characterisation. Energy densities used vary from 53 to 777 mJ/cm(2). PL intensities are determined to be linearly dependent with Ed beyond a threshold of 150 mJ/cm(2) and maximum PL enhancement is a factor of 2.1x. A thermal simulation of the PLA process suggest that PL improvement is proportional to deposited thermal energy and this in the solid state. The calculated melting threshold agrees well with previous work. (C) 1999 Elsevier Science B.V. All rights reserved.