DEFECT CHARACTERIZATION OF ETCH PITS IN ZNSE BASED EPITAXIAL LAYERS

Three distinct etch pit features in ZnSe based epitaxial layers have b een identified. The features were observed with optical dark field mic roscopy and confirmed to be pits using scanning electron microscopy. U sing transmission electron microscopy, we associated different etch pi ts with characteristic crystallographic defects which are common in ep itaxially grown II-VI materials. Frank-type stacking faults form the l argest etch pit followed by a paired configuration of Shockley-type st acking faults. The smallest etch pit is due to a single Shockley-type stacking fault. This study represents one of the first examples of ide ntifying crystallographic defects in II-VI wide bandgap materials usin g etch pit delineation. (C) 1996 American Institute of Physics.