Electrical conduction and mobility enhancement in p-type In-doped Cu2ZnSnSe4 bulks

Cu2Zn(Sn1-xInx)Se-4 bulks with x=0-0.6 were prepared by a liquid-phase reactive sintering method at 600 degrees C. Defect chemistry was studied by measuring electrical properties of In-doped CZTSe (In-CZTSe) as a function of dopant concentration. With increasing the x value from 0 to 0.6, the carrier concentration of In-CZTSe increased from 1017 to 1019 cm(-3) but the hole mobility greatly increased from 1.23 cm(2)V(-1)s(-1) to a maximum value of 8.0 cm(2)V(-1)s(-1) then decreased to about 1.4 cm(2)V(-1)s(-1) at x = 0.6. The largely increased carrier concentration and the slightly changed lattice parameters for In-CZTSe with increasing the In content are related to the precipitated In-rich Cu(2)B(9)BvSe(4) compound and the types of their defects such as Ins(n) and B-Cu. (C) 2014 The Japan Society of Applied Physics