Growth and characterization of some ternary chalcopyrite from the group AlBlllC2Vl semiconductor compound

AgGaS2 single crystals were grown by modified Bridgman method. The present work is devoted to investigate the electrical and thermoelectric transport properties of AgGaS2. Measurements of electrical conductivity and Hall effect were performed in the temperature range (380-660 K) and (344-690 K) for thermoelectric power. Our investigation showed that our samples are P-type conducting . The forbidden energy gap was calculated and found to be 2.57 eV. The analysis of the temperature dependent of electrical conductivity and carrier concentration reveal that acceptor level is located at 0.5 eV above the valance band of AgGaS2.The combination of the electrical and the thermal measurements in the present investigation makes it possible to find various physical parameters, such as mobilities, effective mass, relaxation time, diffusion coefficient and diffusion lengh, both for majority and for minority carriers. In addition to these pronounced parameters, the efficiency of the thermoelectric elements (figure of merit) was evaluated which leads to better application in the field of energy conversation technique, semiconductor devices and electronic engineering.