New defect etchants for CdTe and Hg1-xCdxTe

For the comparative investigations of the structural perfection of both CdTe and (Hg,Cd)Te, new versatile etchants have been developed and are reported in the presented paper. The etching solutions have a similar composition - two components are identical, but one acid is changed. The new etchants are suitable to produce etch pits on {111}A, {111}B, {110}, and other surface orientations of (Hg,Cd)Te and on {111}A surface of CdTe and Cd-rich (Cd,Zn)Te, respectively. The etch pits originate from grown-in dislocations as well as from dislocations produced by mechanical deformations. The etchants detect dislocations with high density (EPD up to 107 cm−2), subgrain boundaries, twins, and inclusions. It is possible to use the etchants both for bulk material and for epitaxial layers with suitable orientations. Furthermore, etching of Hg1-xCdxTe with variable mole fraction x(0⩽x⩽0.75) is possible by varying the dilutions of the etching solutions.