Growth of CdZnTe crystals by the traveling heater method

Our review offers an overview of the Traveling Heater Method (THM) for growing crystals of CdZnTe, the most important semiconductor material available today for fabricating nuclear detectors operable at room temperature. The review compares the advantages of the THM technique with respect to melt growth techniques, and details the development and improvements in the technique from its start to the present day. It is known that the optimization of the growth parameters is highly dependent on the height of the Te-rich CZT molten zone, which in turn governs the shape of the growth interface. Special attention is paid to understand the effect of the Te-rich CZT molten zone on the growth interface (both microscopic and macroscopic) to improve the uniformity and overall quality of the grown crystals. We conclude that this technique affords us the best method today for consistently producing large homogenous detectors in mass quantities with a thickness up to 15 mm. Such detectors are need for many national-security and medical-imaging applications.

► Review of CZT growth by the THM technique. ► Formation of Te-rich secondary phase at the interface. ► Effects on the shape of the growth interface on the crystal quality have been discussed. ► Uniform composition for THM grown ingots compared to melt grown ingots.