Dr. Robby Peibst received the Diploma in technical physics from the Technische Universität Ilmenau, Ilmenau, Germany, in 2005, and the Ph.D. degree in the field of microelectronics from the Leibniz University of Hannover, Hannover, Germany, in 2010. In 2010, he joined the Institute for Solar Energy Research Hamelin, Germany, where he has been leading the group “Emerging Solar Cell Technologies” since 2013. Since 2016, he has been a Professor with the Leibniz University Hannover. His research interests include techniques for producing high-efficient silicon solar cells such as passivating contacts, silicon-based tandem cells, and special applications of photovoltaics.
Title and Abstract of the Speech:
Passivating poly-Si on oxide contacts – from fundamental investigations towards industrial implementation
Passivating poly-Si on oxide contacts and related junction schemes are in the focus of public c-Si PV research over seven years now. The first investigation phase was characterized by basic research on the current transport mechanisms, the evaluation of different manufacturing processes for this junction scheme, and by the experimental demonstration of the high efficiency potential on laboratory cells. As summarized in the talk, new excellent results and valuable insights are still reported for each of these topics. Nevertheless, the current phase focusses on the transfer to industrial mass application. It is not fully clear yet which cell concept can utilize POLO-junctions best in terms of efficiency potential, process flow leanness and low material consumption. Even the most common structure – an n-type frontjunction cell with an n+ POLO junction on the rear – has, despite of demonstrated industrial record efficiencies above 24 %, a hard standing as compared to the existing benchmark PERC. The talk will outline this area of suspense. A new challenger to advanced c-Si technology also appears to be emerging in the form of silicon perovskite tandem cells, which promise much larger leverage. The lecture will also report that POLO junctions are not a dead end but rather can be an essential component of tandem cells based on high temperature processed Si-bottom cells.