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 investigated. 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 (PSD) of Y+, Zr+, YO+ and ZrO+ begins at approx. 2.5 MW/cm2. We interpret this as the onset of laser ablation. Cation mass spectra collected using higher laser fluences resemble those obtained via secondary-ion mass spectrometry (SIMS). The similarity between the laser ablation and SIMS data demonstrates the importance of surface electronic structure effects in photon induced degradation of this material