David Lidzey of the University of Sheffield and colleagues there and at the University of Cambridge, Cardiff University and Diamond Light Source, are investigating the plastics used in a new type of low-cost solar cell with a view to improving efficiency. A key aspect of developing efficient plastic-based photovoltaic devices depends on control morphology within a thin organic semiconductor film to maximize efficiency of charge-generation and charge-extraction. The team demonstrated that the drying process and consequent crystallization occurs in three steps with the second stage being the most important in polymer rapid crystallization. Such insights could allow them to optimize the process.