Back-side AlOx Passivation material and technology for the application of high efficiency (20%) and low cost PERC solar cells

In this paper, we developed a novel and economic deposition technique for AlOx layer by applying our novel material - “AlOx Passivation Paste” (IP1257) using screen printing which is a standard process/equipment available in all cell manufacturers. As a result, capital investment in high cost equipment could be reduced. After process integration with commercially available screen-printed contact opening process, the highest conversion efficiency of 20.11% with V OC of 0.655 V and I SC of 9.30 A for standard Mono pseudo square wafers (156 mm) have been achieved. This could be attributed to an excellent rear side passivation quality by the IP1257-AlOx/SiNx stack. Finally, we believe that this technique could become a good solution and option for the next generation of high efficiency PERC-type solar cells.