Si solar cells currently occupy more than 90% market share in PV modules worldwide. Standard diffused junction Si solar cells have been the primary contributor to this. In the last few years, there have been revolutionary advancements in Si solar cell technology that enhances photovoltaic conversion efficiency beyond the two decade old record efficiency value of 25%. Two such technologies are Si heterojunction and interdigitated back contact solar cells and they currently hold record efficiency values for modules with cell efficiencies approaching the theoretical limit of single junction Si solar cell. However, these newer technologies contribute only ~ 6% to current PV market. In this talk, I will discuss the fundamentals and processing challenges that require extensive R&D effort to adopt these technologies for wide spread high volume manufacturing.
Dr. Ujjwal Das is currently an Associate Scientist at Institute of Energy Conversion (IEC) at the University of Delaware. He received his Ph.D. degree from Indian Association for the Cultivation of Science (IACS) in Jadavpur, India and achieved several accolades including best paper award in National Solar Energy Convention - India, Young Scientist award from International Union of Crystallography and Young Researcher award from Japan Society of Applied Physics. At the University of Delaware, He initiated work on Si heterojunction solar cell at IEC. In 2007, he and his group have first proposed and demonstrated a new PV cell architecture, IBC Si heterojunction cell that is widely believed to be the ultimate high efficiency Si solar cell design. In the past couple of years, three highest Si solar cell efficiency records have been recorded by 3 different groups using IBC Si heterojunction structure. Several US, European and Japanese PV manufacturer is considering bringing the technology into market. He has served as PI / co-PI in multiple US government (DOE, DARPA and NSF) and industry (SunPower, BP Solar, AirProducts) funded project and served as consultant for several companies. Dr. Das has or is currently mentoring 12 Ph.D. Students and has authored / co-authored more than 70 peer reviewed papers and one US patent.