CsLiB6O10 (CLBO) thin films are grown on Si (100) and (111) substrates using lower index SiO2 and CaF2 as buffer layers by pulsed KrF (248 nm) excimer laser ablation of stoichiometric CLBO targets over a temperature range of 425 to 725°C. A CaF2 buffer layer is grown on Si by laser ablation while SiO2 is prepared by standard thermal oxidation. From extended x-ray analysis, it is determined that CaF2 is grown with preferred orientation on Si (100) at temperatures lower than 525°C while on Si (111) substrate, CaF2 is grown epitaxially over the temperature range; this agrees well with observed reflection high energy electron diffraction patterns. X-ray 2θ-scans indicate that crystalline CLBO are grown on SiO2/Si and CaF2/Si (100). Analysis of reflectance spectra from CLBO/ SiO2/Si yields the absorption edge at 182 nm. Surface roughness of the CaF2 and CLBO/CaF2/Si film are 19 and 15 nm, respectively. This relatively rough surface caused by the ablation of wide bandgap CaF2 and CLBO limits the application of CLBO for waveguiding measurement.
Bibliographical noteFunding Information:
This work is supported by Navy Grant No. N00014-92-J-1903 through the Center for Nonlinear Optical Materials at Stanford University.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry