Zinc and selenium co-doped CdTe substrates lattice matched to HgCdTe

Abstract A CdTe crystal co-doped with zinc and selenium was grown by the gradient freeze method to obtain substrate material which is lattice matched to HgCdTe. After the measurement of the segregation coefficient of each dopant, a charge composition was estimated to realize a uniform and suitable lattice constant. The crystal grown from the charge exhibited not only a very uniform lattice constant within the range of fraction solidified between 0 and 0.7, but also high crystal perfection as indicated by low dislocation density (3×10 3 cm −2 ) and high infrared transmission (>62%). CdTe doped with Zn and Se is therefore a very promising material as a substrate of HgCdTe epitaxial growth.