Nancy Haegel: Transport imaging uses photons to measure efficiency in solar cells

Nancy M. Haegel is Center Director for the Materials Science Center in the Materials and Chemical Sciences Directorate at the National Renewable Energy Laboratory (NREL). The Materials Science Center provides fundamental and applied materials science discovery and problem-solving for current and next-generation renewable energy and energy-efficient technologies. Nancy has had previous appointments on the faculty at the University of California, Los Angeles, Fairfield University and the Naval Postgraduate School, where she was Distinguished Professor of Physics. She received a BS degree in Metallurgical Engineering and Materials Science from the University of Notre Dame and a PhD in Materials Science from UC Berkeley. Her research interests are in semiconductor materials, transport and characterization. She was a 2012 Fulbright Senior Scholar at Hebrew University in Jerusalem studying near-field optics.

Helio Moutinho has a bachelor in Physics from the Federal University of Rio de Janeiro, and MS in Materials Science from the Military Institute of Engineering (IME), both in Rio de Janeiro, Brazil, and a PhD in Materials Science from the Colorado School of Mines. He joined IME in 1981, where he worked as research assistant and later as Associate Professor, and the National Renewable Energy Laboratory in 1987, where he currently holds the position of Senior Scientist. Helio has worked for over 30 years on the investigation of structural and electrical properties of PV materials and devices, such as CdTe, Si, CdS, InP, and CZTS, and specializes in analytical techniques such as atomic force microscopy (AFM), scanning capacitance microscopy, scanning Kelvin probe microscopy, conductive AFM, scanning electron microscopy, electron backscatter diffraction, electron-beam induced current and energy dispersive X-ray spectroscopy. His current interests include the development of near-field transport imaging for the investigation of carrier transport in PV materials.

Chuanxiao 'Nick' Xiao is currently a graduate student in the Metallurgical and Materials Engineering Department at the Colorado School of Mines. He is engaged in research at NREL under the supervision of Dr. Mowafak Al-Jassim. Nick's research area is scanning probe microscopy including AFM- and SEM-based techniques with a focus on solar cell materials and devices. Nick received his BS in Physics from Sun Yat-sen University, Guangzhou, China, and an MS in Physics from the University of Toledo.

The Microscopy and Imaging Group at NREL (Mowafak Al-Jassim, Group Manager) focuses on investigating defects, interfaces and junctions in a range of materials and devices relevant to renewable energy and energy efficient technologies. The group is a world leader in the science and characterization of photovoltaic/semiconductor materials. It uses Angstrom-, nano- and micron-scale techniques to study the structural, morphological, chemical, micro-electrical and micro-luminescent properties with special emphasis on correlating fundamental material properties with device performance. The microscopy techniques deployed are in three broad categories (TEM, SPM, SEM), that include a wide collection of state-of-the-art ancillary techniques, such as EELS, EDS, SCM, SKPM, cryogenic CL, EBSD and EBIC.