Europium doping of c-BN and ta-C thin films

Abstract

We investigated the doping of thin films of tetrahedral amorphous carbon (ta-C) and cubic boron nitride (c-BN) with europium. The films were grown by mass selected ion beam deposition and doped with europium during growth. Analysis was performed in vacuo using photoelectron spectroscopy and ex vacuo with conversion electron Mossbauer, Fourier transform infrared and cathodoluminescence spectroscopy. Successful incorporation of europium into the c-BN films is achieved. These c-BN:Eu films show luminescence of the D-5(0)-F-7(2) intra-4f electron transition, measured at 12 and 300 K. The results are compared to Eu implanted poly crystalline c-BN. In case of the ta-C films doped with Eu during growth an accumulation of the deposited Eu atoms at the surface is observed. (C) 2002 Elsevier Science B.V. All rights reserved.