Effect of Electric Field on the Spray Deposited PEDOT: PSS Film

Poly (3, 4-ethylenedioxy thiophene): poly(styrenesulfonate) hole transport layer (HTL) is deposited using a spray nozzle and gas pressure for atomisation. An electric field created by the voltage applied (500 volt) to the nozzle helps create coulomb fission and also the polarisation effect needed for annealing. SEM results show that the film morphology becomes much smoother when the voltage is applied. By four probe measurement it was found that sheet resistance got reduced (from 400 Ω/□ to75 Ω/□) and I-V measurement indicated conductivity enhancement due to the application of electric field. The process duration is only 2-3 min and the range of applied voltage is quite low as compared to other techniques.