Passivation films with SU-8 polymers for organic solar cell protection from ultraviolet ray

This paper investigates passivation films for organic solar cells (OSCs) in terms of the ultraviolet (UV) rays that the SU-8 film employs. An SU-8 film was deposited on the back side of an OSC sample, and the performance of the OSC was measured in terms of the UV intensity variation. The UV intensity was 10 and 30 mW/cm2 at 365 nm. When 30 mW/cm2of UV was irradiated for 5 min, the Voc and FF of the OSC without SU-8 film significantly decreased to 70% and 74%, respectively, from the pristine condition; leading to an efficiency decrease of approximately 48%. However, the Voc and FF of OSC with passivation film slightly decreased to 93% and 98%, respectively.