Nanocrystalline transparent SnO2-ZnO films fabricated at lower substrate temperature using a low-cost and simplified spray technique

Nanocrystalline and transparent conducting SnO2-ZnO films were fabricated by employing an inexpensive, simplified spray technique using a perfume atomizer at relatively low substrate temperature (360+/-5 degrees C) compared with conventional spray method. The structural studies reveal that the SnO2-ZnO films are polycrystalline in nature with preferential orientation along the (101) plane. The dislocation density is very low (1.48x10(15) lines/m(2)), indicating the good crystallinity of the films. The crystallite size of the films was found to be in the range of 26-34 nm. The optical transmittance in the visible range and the optical band gap are 85% and 3.6 eV respectively. The sheet resistance increases from 8.74 k Omega/ to 32.4 k Omega/ as the zinc concentration increases from 0 to 40 at.%. The films were found to have desirable figure of merit (1.63x10(-2) (Omega/ )(-1)), low temperature coefficient of resistance (-1.191/K) and good thermal stability. This simplified spray technique may be considered as a promising alternative to conventional spray for the massive production of economic SnO2-ZnO films for solar cells, sensors and opto-electronic applications. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim