Page 117 - ISES SWC50

Sigurd Wagner
Country: USA
Year Started Research: 1973
Title of Research: CuInSe2/CdS heterojunction photovoltaic detectors
University: Bell Telephone Laboratories
Still Active in Research: Yes

Sigurd Wagner is Professor Emeritus of Electrical Engineering and Senior Scholar at Princeton University, where he
has been working since 1980. He received his Ph.D. in physical chemistry in 1968 from the University of Vienna in
Austria, came to the US as a post-doc at Ohio State University, worked at the Bell Telephone Laboratories from 1970
to 1978, and organised solar cell research as the founding chief of the Photovoltaic Research Branch at the Solar
Energy Research Institute (SERI, now NREL) from 1978 to 1980. At Bell Labs he pioneered the fabrication of junction
devices from chalcopyrites, a class of ternary compound semiconductors. Intense interest in green light-emitting
diodes led to the p-CuGaS2/n-CdS heterojunction (1973). The p-CuInSe2/n-CdS heterojunction photodetector was
motivated by then-anticipated, GaAs laser-based, fiber-optical communications (1974); this device’s surprisingly
high, broadband, quantum efficiency made it an efficient solar cell (1975). Solar cells of CuInS2, CuGaSe2, the
quaternary compound Cu2CdSnS4, and InP followed, as well as isotype heterojunctions and photochemical
electrodes. In 1978 Wagner joined SERI to initiate and organize its solar cell research program. Pursuing his primary
interest in research he moved to Princeton in 1980, focused until the mid-1990s on hydrogenated amorphous
silicon for solar cells, then transitioned to a program on a-Si thin-film transistors. TFTs became the vehicles for
foundational experiments on large-area electronics made of flexible, shapeable, and elastically stretchable opto-
electronic surfaces, including their basic design rules and architecture. Wagner is considered to be the father
of the field of electronic skins. At present he is working with his colleagues Jim Sturm and Naveen Verma on
complete large-area hybrid thin-film/CMOS systems for sensing applications. He continues to enjoy and greatly
benefit from collaborations with colleagues and students, which still extend to occasional excursions into solar
cell research.

Zhiqiang Yin

Country: China
Year Started Research: 1978
Title of Research: Solar Thermal
University: Tsinghua University
Still Active in Research: Yes

Yin Zhiqiang, is a Professor at Tsinghua University, Beijing and is the Chief Scientist for Tsinghua Solar Ltd., Beijing,
China, and has been working on solar thermal since 1978. He invented “Al-N/Al selective absorbing surface” using
a single-cathode magnetron sputtering, which has optimum solar absorptance and emittance with low cost. He also
invented the “Water-in-glass” close-coupled solar water heater, and “E-W” direction of tubes of solar collectors and
systems. He and co-workers developed the production line for manufacturing all-glass evacuated collector tube,
all-glass evacuated tube collector and systems. He is the first author of three China national standards-“All glass
evacuated solar collector tube”, “Test methods for thermal performance of domestic solar water heating systems“
and “Specification of domestic solar water heating systems“ which are useful for supporting the developments
of solar thermal industry. Today he is the project leader of ISO 22975-4 Solar Energy – Collector components
and materials Part 4: Glazing material durability and performance. The Solar Water Heater industry has realized
commercialization and has solar water heater’s production chain including borosilicate glass 3.3 tube, sputtering
coaters, machinery tools, welding machine and polyurethane casting machine, etc. China has total installed capacity
of solar collectors in operation of approximately 374 million m2, 2013, which was around the world market share
of 70.0%, saving about 43 million tce. All-glass evacuated tubular collectors have over 80% of the domestic market
share in China and have been exported to many countries in the world. China has been the biggest producer and
user of solar water heaters since the 1990s, and solar thermal conversion is environmentally friendly, especially the
contribution to mitigate CO emission.
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