Surface structural and etching studies on high-temperature solution grown GdAlO3 crystals

Surface structural studies of as-grown GdAlO3 crystals revealing formation of microdisc elevations, growth fronts, solid inclusions and etch pits are reported. It is suggested that the etch patterns on as-grown different surf aces of the crystals may be due to etching during cleaning process of cryst als. Etch patterns on GdAlO3 crystal surfaces are described and discussed. Defect structures on GdAlO3 crystals include impurity sites, dislocations, low-angle grain boundaries and twinning (simple as well as complex). Result s of etching kinetics of H3PO4-GdAlO3 surface system are reported. H3PO4 is shown to be a suitable dislocation etchant for GdAlO3. The activation ener gy and Arrhenius factor for dissolution parallel, and perpendicular, to the surface for new pits (developed due to laboratory etching) are estimated f or these crystals using graphical methods. (C) 2000 Published by Elsevier S cience S.A.