Thin Solid Films, Vol.518, No.17, 4821-4827, 2010
Evaluation of different deposition conditions on thin films deposited by electrostatic spray deposition using a uniformity test
Copper indium disulphide films were produced by electrostatic spray deposition using a water/alcohol solution of copper chloride (CuCl(2)), indium chloride (InCl(3)) and thiourea (CS(NH(2))(2)) sprayed onto SnO(2):F coated glass substrates. The influence of various deposition parameters, namely substrate temperature (380-450 degrees C), applied voltage (12-18 kV), solution concentration (0.21-0.49 M), flow rate (25-200 mu l/min) and needle-substrate distance (40-70 mm) were investigated, particle image velocimetry measurements were made of the spray cone and correlated with the film uniformity. The film uniformity was measured using an optically based test developed in-house. Results show that the highest concentrated spray solution and lowest deposition temperature produce non-uniform films. In contrast, a needle-substrate distance of 50 mm, and the lowest applied voltage and flow rate resulted in the most uniform films. (C) 2010 Elsevier B.V. All rights reserved.
Keywords:Copper indium sulphide;Electrostatic spray deposition;Uniformity;Solar cells;Velocimetry;Thin films