Study of the extended defects in CdZnTe crystal

Abstract

Etch pit real-time observation (EPRTO) technique was employed to study the extended defects in CdZnTe materials. By tracking the pyramidal etch pits on the (1 1 1) A surface etched by Nakagawa etchant, the microstructures inside the extended defects were revealed. The extending directions of the extended defects and corresponding crystallographic orientations were determined by measuring the displacement vectors of the etch pit tips. Then the orientation distributions of the extended defects in CdZnTe samples were obtained and displayed on the [1 1 1] pole figures. The results show that the extended defects in CdZnTe material consist of dislocation lines connected by micro precipitates or dislocation jogs. The extending directions of the defects situate on the connection lines of [0 1 1], [1 0 1] and [1 1 0] on the [1 1 1] pole figure. The defects with extending directions of 〈2 1 1〉 or 〈3 2 1〉 outside the connection lines of [0 1 1], [1 0 1] and [1 1 0] cannot be revealed by Nakagawa etchant. The orientation distribution of the extended defects shows that the pyramidal etch pit density (PEPD) is not sufficient to describe the property of the extended defects in CdZnTe materials. Some additional parameters are proposed for a more comprehensive evaluation.