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Steven Ringel



Steven A. Ringel is the Neal Smith Endowed Chair Professor in the Department of Electrical and Computer Engineering at The Ohio State University. He is also the founding and current Executive Director of The Ohio State University Institute for Materials Research (IMR), and he is the Faculty Director of Ohio State’s Materials and Manufacturing for Sustainability (M&MS) Discovery Theme. IMR is Ohio State’s largest non-medical research center, with more than 200 faculty members from 22 academic departments in 5 colleges, performing more than $75M in annual research on a base of awards valued at more than $400M. Within the IMR umbrella are state-of-the-art core facility centers, national centers of excellence and industry-university consortia. The M&MS Discovery Theme is a paradigm-shifting effort at Ohio State to create pre-eminence in materials and technologies for sustainability, focusing on innovation and industry deployment.

Professor Ringel is internationally recognized for his seminal contributions and leadership in the field of electronic materials and devices, particularly in photovoltaics, defect characterization techniques, wide bandgap semiconductors, and compound semiconductor-silicon integration. Specific to photovoltaics (PV), Dr. Ringel has spent much of his career making high impact contributions; his early work on CdTe solar cells revealed basic mechanisms behind the now standard cadmium chloride treatment applied in this global technology, his efforts in space PV resulted in the highest performance InP space solar cells at the time, and his group is world-recognized for its advancement of PV based on III-V/SiGe materials. More recently, his group has produced the first large area, III-V/active-Si tandem and triple junction cells, translating these high-performance, low-cost technologies to industry. Dr. Ringel’s general focus on materials defects, their characterization and growth mitigation strategies have similarly made lasting impact on wide bandgap device technologies, including the invention of deep level optical spectroscopy methods that have been adopted by industry to solve GaN reliability issues. As co-founder and editor of the IEEE J-PV, the General Chair of the 2015 42nd IEEE PVSC and the former Chair of the international IEEE Photovoltaics Technical Committee, Dr Ringel has helped to define future directions in PV research and education.

Professor Ringel has authored and co-authored more than 300 technical articles and conference presentations, given more than 120 invited talks, and has authored or edited 4 books and numerous chapters. At OSU he has produced more than 70 PhD and MS students. His recognitions include the 1994 NSF National Young Investigator Award, the Ohio State Distinguished Scholar Award, the Ohio State Scott Award for Outstanding Academic Achievement in Engineering, the OSU Harrison Award for Excellence in Engineering, seven best paper awards from international conferences and societies, AAAS Fellow and AIAA Associate Fellow. He sits on several international boards (Tyndall Institute in Ireland, Singapore-MIT Alliance for Research and Technology (SMART) - for which he is chair of the LEES IRG board, and the Sandia National Labs UWBG center), he has been a visiting professor numerous times (UPM-Spain, NTU-Singapore, Cardiff), and he is a co-founder of several startup companies. Dr. Ringel received his Ph.D. degree in Electrical Engineering from Georgia Tech in 1991, and his M.S. and B.S. degrees from Penn State in 1986 and 1984, respectively.


Ph.D. 1991, Georgia Institute of Technology

Research Interests

Electronic materials and devices, photovoltaics, defect engineering, epitaxy and innovation in defect characterization methods; Broad interests in the science and application of electronic materials for applications in energy, electronics and optoelectronic technologies; Defect engineering in semiconductors and development of methods for trap spectroscopy; with applications to wide bandgap semiconductor devices and new materials; Substrate engineering; heterogeneous integration and interface science; The academic-industry research interface; Translational materials and its role in global innovation in solar energy, next generation electronics and general technology development.


375 Caldwell Laboratory

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