Electrical properties of patterned photoactive layers in organic photovoltaic modules

The scaling of thin film photovoltaics to a commercially viable size relies on the series connection of multiple small cells into modules. These interconnections are typically formed by three patterning steps, each of which have an impact on the series resistance and consequently on the total module performance. Here, we implement the transmission line method for the complete analysis of the P2 patterning step of the photoactive layer in organic photovoltaic modules. Devices are investigated with a sample design that allows for a comparative study of the P2 connection on the solar cell performance. We compare subtractive mechanical scribing to a newly developed additive pre-patterning method for the P2 step. Aerosol Jet printed pre-patterning lines of low surface energy and conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) modified with a fluorosurfactant repel the subsequently spray coated photoactive layer. Furthermore, the influence of MoO3 in the P2 pattern is elucidated, displaying a substantial increase in series resistance and decrease in device performance.