The Electronics of Thin Film Organic Photovoltaics

Abstract

In this chapter, the aim is to investigate how the donor/acceptor interface of OPV devices affects the performance. In the second section of this chapter this effect is studied by using a bi-layer (p-n junction morphology) instead of a blended one, for the photoactive, the aim is to understand excitonic effects. From this it’s possible to fabricate base junction devices using a bi-layers (p-n junction morphology) instead of a blended one, for the photoactive layer. In the fabrication of the p-n junction OPV device, dynamic spin coating is used as a deposition technique. After the first layer of P3HT is spin-coated onto the substrate, PCBM is then deposited using dynamic spin coating. By varying the spin-coating parameters, a device structure of ITO/PEDOT:PSS/P3HT/PCBM/Al with a range of P3HT/PCBM interface morphologies, from low level inter-digitated structure to direct flat contact, is demonstrated. Device PCEs are correlated to the film thickness and interface morphology of the active layer. In the fabrication of the p-n junction OPV device, dynamic spin coating is used as a deposition technique. After the first layer of P3HT is spin-coated onto the substrate, PCBM is then deposited using dynamic spin coating. By varying the spin-coating parameters, a device structure of ITO/PEDOT:PSS/P3HT/PCBM/Al with a range of P3HT/PCBM interface morphologies, from low level inter-digitated structure to direct flat contact, is demonstrated.