Printing Hybrid, Interdigitated Back Contact Solar Cells

Interdigitated back contact solar cells were fabricated entirely with inkjet printing. PEDOT: PSS films with co-solvents and TiO2 suspension were printed on a textured silicon substrate with only one inkjet printer as was the metal ink. Adding co-solvent to the PEDOT:PSS and passivation of the Si surface significantly reduced the losses and enhanced the short circuit current, Jsc, and, as a result, improved the fill factor and efficiency of the devices. Although the thickness of PEDOT: PSS layer is approximately one micrometer, which is thicker than the optimal range typically reported, there is still adequate short-circuit current, Jsc, suggesting that there is a relatively large processing window for the PEDOT: PSS film fabrication. To further improve the performance of the devices, an anti-reflective coating on the front side is required. Also, an improved metal contact ink is needed to improve the contact resistance between the PEDOT:PSS layer and the metal contact.