Influence of Mg doping on electrical properties of Cu(In,Ga)Se2 bulk materials

Mg-doped CIGSe bulk materials with the Cu-0.9[(In0.7-xMgx)Ga-0.3]Se-2 formula at x = 0-0.15 were prepared at 650 degrees C. A two-step liquid-phase reaction sintering technique has been used in rather low temperature for the densification of Mg-doped CIGSe bulk materials with Sb2S3 and Te sintering aids. Electrical property was studied by measuring the mobility and concentration of charge carriers. All Mg-doped CIGSe pellets showed a p-type behavior. The favored low hole concentration of 2.86 +/- 10(16) cm(-3) and mobility of 4.23 cm(2)/V s were achieved for CIGSe materials doped with 10% of magnesium, as compared to 3.25 +/- 10(16) cm(-3) and 1.16 cm(2)/V s for undoped one. The explanations based upon the Mg-to-Cu antisite defect and the Mg-to-In defect for the changes in electrical property were declared. The study in bulk Mgdoped CIGSe has been based upon defect states and is consistent and supported by the data of lattice parameters. (C) 2013 Elsevier B.V. All rights reserved.