ZnTe

ZnTe, or zinc telluride, is a binary semiconductor compound consisting of zinc and tellurium. It belongs to the II-VI family and is widely studied for its direct wide-bandgap properties. At room temperature, ZnTe most commonly adopts the zinc blende crystal structure, though nanostructured samples can show alternative polytypes such as wurtzite under certain growth conditions.

Electronic and optical properties: ZnTe has a direct bandgap of about 2.26 eV at room temperature, placing its absorption edge in the visible region and its photoluminescence in the green to blue part of the spectrum. It exhibits strong optical transitions and is used in optoelectronic devices. The material can form heterostructures with other II-VI materials such as ZnSe and CdTe, enabling quantum wells and diode structures.

Preparation and structure: Bulk ZnTe crystals are grown by methods such as the Bridgman or Czochralski techniques. Thin films and heterostructures are routinely produced by molecular beam epitaxy or metal-organic chemical vapor deposition. Chemical vapor transport can be used to obtain high-purity crystals for research.

Doping and challenges: Native defects commonly make ZnTe n-type; achieving stable p-type conductivity is challenging due to self-compensation. Doping with selected acceptors (for example nitrogen or copper in some regimes) and careful growth conditions are used to realize p-type material, but performance remains limited in many cases.

Applications: ZnTe is used in blue-green light-emitting devices, laser diodes, photodetectors, and as a component in ZnTe-based heterostructures for quantum-well studies and optoelectronics research. Its compatibility with other II-VI materials makes it a candidate for multi-material devices.