CHEMICAL ETCHING OF (100) AND (110) FACES OF FLUX-GROWN LABO3 CRYSTALS

Experiments on the etching of (100) and (110) faces of LaBO3 crystal s urfaces are offered. The results reveal HNO3 to be a dislocation etcha nt for both LaBO3 crystal faces. It is shown that the shape of the etc h pits due to HNO3 is different for different habit faces. The depende nce of the etch rates for (100) and (110) faces (lateral as well as ve rtical) on the concentrations and temperature of the etchant, are desc ribed and discussed. It is shown that the faces resist attack of the e tchant in the direction of the normal to the surface after 2 h of etch ing irrespective of the concentration of the etchant used at different temperatures. It is further shown that till the time the passivity se ts in, the variation of depth with etching time is linear in all the c ases.