Symposium ES20-Thin-Film Chalcogenide Semiconductor Photovoltaics

Recent advances in thin film compound semiconductor photovoltaics have demonstrated much of the high potential of these technologies for generating sustainable and cost-efficient energy, with demonstrated conversion efficiencies above 20% and several advantages in manufacturing and materials costs. It is remarkable that cell technologies achieve device and cost performance at least as good as multicrystalline Si, while having extended defect and interface densities 100-1000 times higher. Advances have been enabled by significant breakthroughs in the fundamental understanding and manipulation of the established thin film materials sets. Emerging areas of research include the materials science of degradation of chalcogenide cells and modules at multiple length scales, further reduction of bulk and interface recombination, understanding whether their microstructure will limit their approach to their theoretical maximum performance, and incorporation of thin film compound semiconductor cells in multijunction devices. At the same time, newer promising materials technologies have already emerged with >10% efficiency and remain ripe for further development. Such advances must come through establishment of deep fundamental understanding of the materials, surfaces and interfaces, device properties, and fabrication processes.

The proposed symposium will focus on the science of single and polycrystalline materials, defects, interfaces, and devices, development of characterization methods, and advancement of manufacturing processes in thin film compound photovoltaic solar cells and related applications. Relevant materials include chalcogenide semiconductors and their partner layers especially (Ag,Cu)(In,Ga)(S,Se)₂ (CIGSe and related alloys), Cu₂ZnSn(S,Se)₂ and CdTe and its related alloys. Other chalcogenide, chalcopyrite and novel absorber materials, heterojunction partner layers, chalcogenide tandem devices are also of high interest. Reviews on innovative technological developments and fundamental scientific insights on materials will be included. The symposium will feature a strong program of technical abstracts, a panel discussion on industry-relevant topics, as well as a “Young Scientists Tutorial” for characterization, design and reliability of PV module materials.

Topics will include:

Methods for the synthesis and growth of thin film and bulk compound semiconductors for photovoltaic applications
Absorbers with superior photovoltaic properties, especially high ratio of minority carrier diffusion length to optical absorption length
Carrier selective, low recombination, low resistance contact structures
New characterization techniques for isolating and studying bulk minority carrier lifetime, surface recombination, defect levels, and junction properties
Materials theory and first principle computation for understanding the limitations of current solar cell materials and for designing new material systems
Device modeling for understanding the shortfalls in current device designs and/or for interpreting characterization results
Understanding of materials processing, especially post-deposition treatments
Surfaces, interfaces, and extended defects, such as the characterization and modeling of dislocations, grain boundaries, microstructure, inhomogeneity, and potential fluctuation
Manufacturing topics, including advances in process scaling, module integration, and manufacturing metrology
Materials science of thin film compound semiconductor modules including materials integration, degradation, and reliability

Invited Speakers:

Jeff Bailey (Miasole, USA)
Stephan Buecheler (Empa - Swiss Federal Laboratories for Materials Science and Technology, Switzerland)
Markus Gloeckler (First Solar, USA)
Charles Hages (University of Florida, USA)
Amit Munshi (Colorado State University, USA)
Akira Nagaoka (Kyoto University, Japan)
Sascha Sadewasser (International Iberian Nanotechnology Laboratory, Portugal)
Adele Tamboli (National Renewable Energy Laboratory, USA)
Mirjam Theelen (TNO, Netherlands)
Dragica Vasileska (Arizona State University, USA)
Pawel Zabierowski (Warsaw University of Technology, Poland)