Fabrication of solution-processed thin film solar cells,such as polymer and perovskite solar cells,is a new and exciting application of Spray Technology.To address the efficient and low-cost fabrication of solar cell materials,we have recently developed a novel spray coating method,i.e.,substrate-vibration-assisted spray coating(SVASC)to improve surface wetting and coverage.In this work,the precursor solution of PEDOT:PSS+carbon nanotubes(CNTs)+2-propanol was sprayed on a vibrating glass substrates to form PEDOT:PSS thin films.PEDOT:PSS is a solution-processed solar cell material and can be used to make thin films using a casting method.The doping of PEDOT:PSS thin films with highly conductive,high energy level substances,such as CNTs results in enhanced hole conductivity.The surface topography,coverage and morphology of spray-on films and the effect of the substrate vibration power are studied using laser microscopy technique.Results show a significant improvement in the electrical conductivity of CNT-doped-PEDOT:PSS films,when the substrate is subjected to a low ultrasonic vibration of 5 W.It is found that a high power substrate vibration makes the solid film non-uniform and nonconductive.The substrate vibration imposes disturbances on the impinged spray droplets affecting droplet spreading,coalescence,liquid film formation,etc.