wned alternative energies expert at DEK Solar, Tom Falcon has spent a large part of his career developing techniques to optimise frontside conductor printing on silicon solar cells. His team’s latest research, revealed in the new white paper, characterises the variables within an optimised PoP process and offers clear, concise descriptions of how to effect this within existing printing processes. One of the only routes to higher aspect ratio silver conductors in a volume manufacturing environment, PoP enables cell manufacturers to print higher, narrower collector grid features onto the front of solar cells. This in turn allows more sunlight through to the silicon, optimises the grid’s electrical performance, and delivers the high efficiency energy conversion capabilities that are key to future success.
Commenting on his new white paper, Tom Falcon explains: “This paper offers an in-depth study of some of the most important aspects of the PoP process such as screen and mesh types, emulsion thickness, aperture widths, paste types and process parameters. The discussion is clear and empirical, making this a no-nonsense, down-to-earth guide to what is required in terms of material and processes. It’s designed to enable manufacturers to develop an optimised PoP process that is capable of delivering major improvements in conductor aspect ratios. We’ve seen dramatic efficiency gains proven to be sustainable in production volumes over many wafers. Here at DEK, we’re committed to continual innovation in the quest for grid parity and beyond. I think this paper reflects this ethos, in addition to providing an extremely useful resource for anyone interested in increasing solar cell efficiencies easily, quickly and with minimal outlay.”
Since PoP delivers these advances by enabling the metallization grid to be printed onto the solar cell twice, repeatable accuracy is the enabler. Even the slightest misalignment can result in wider features and a reduction in cell efficiency. As such, along with process engineering expertise and global support capabilities, DEK Solar’s capacity to drive new advances in this area is boosted by advanced metallization technologies such as the recently introduced Eclipse platform. Representing an entirely new modular platform design concept, Eclipse incorporates a series of field-retrofittable process modules that enable manufacturers to easily scale production to 1200, 2400 or 3600 wph. In addition, the platform’s inherent accuracy and repeatability is ideal for progressive techniques such as print-on-print.