Cu2ZnGeSe4 single crystals: Growth, structure and temperature dependence of band gap

Abstract

This work describes the production of single crystals of the semiconducting quaternary compound Cu2ZnGeSe4 using a gas chemical method in which iodine was used as a transporter. For all the synthesized samples, their phase state, crystal structure syngony and lattice constants were refined. The unit cell of the studied compound is characterized by tetragonal symmetry. The transmission spectrum was applied to calculate the band gap, which is depicted as temperature function in 20–300 K range. It was fixed that the band gap increases by 12% with decreasing temperature.