Impact of low temperature plasma annealing for flexible, transparent and conductive ITO/PEDOT:PSS composite electrode

We report on the development of a cost effective, highly transparent flexible conductive electrode for energy conversion devices using the ITO/PEDOT:PSS nanocomposite. The ITO/PEDOT:PSS nano composite thin film was deposited via bar coating, then its characteristics were examined. In particular, we study any changes in its transparency and resistance. The thin film transparent ITO/PEDOT:PSS was annealed using a low temperature annealing technique called plasma annealing. The purpose of low temperature plasma annealing is to help excite the electrons from their bonding states in the valence band into the antibonding states of the conduction band where a second order phase transition occurs. This study investigates the influence of O₂ plasma annealing on the resistance of the nano composite thin films. The included PEDOT:PSS supports the flexibility of the ITO, as pristine ITO is brittle. High optical transmittance of 93.73% at 550 nm and a reduction in the sheet resistance were achieved using this plasma annealing from 1105 Ω/□ to 535 Ω/□ on the ITO/PEDOT:PSS nano composite making them excellent candidates to develop as cost effective flexible transparent electrodes that can be used as thin film heaters.