PHOTON-STIMULATED DESORPTION OF CATIONS FROM YTTRIA-STABILIZED CUBIC ZRO2(100)

The positive ion yield resulting from the interaction of a pulsed 266- nm laser with yttria-stabilized cubic zirconia crystals is investigate d. Although the photon energy (4.66 eV) is well below the nominal band -gap energy for ZrO2 (5.0-5.5 eV), photon stimulated ion desorption (P SD) of Y+, Zr+, YO+ and ZrO+ begins at similar to 2.5 MW/cm(2). We int erpret this as the onset of laser ablation. Cation mass spectra collec ted using higher laser fluences resemble those obtained via secondary- ion mass spectrometry (SIMS). The similarity between the laser ablatio n and SIMS data demonstrates the importance of surface electronic stru cture effects in photon induced degradation of this material. (C) 1998 Pacific Northwest National Laboratory. Published by Elsevier Science B.V.