9604915 Wu This award supports cooperation between Yue Wu and Daxing Han, University of North Carolina, Chapel Hill, and Kong Guanglin, Institute of Semiconductors, Chinese Academy od Sciences, Beijing, on the role of hydrogen in the metastability of hydrogenated amorphous silicon. The research problem is an important one that has not been satisfactorily addressed despite much research over the years. The investigators propose a joint study of infrared absorption and nuclear magnetic resonance to explore the metastable photostructural effects associated with extended illumination. The Chinese group has recently published results that are somewhat controversial; cooperation in further research in this area will allow the US team to advance current understanding by attempting to replicate results on other samples of amorphous silicon produced by other growth techniques. Advances in this research could contribute to improved technology in both photovoltaics and flat-panel displays. This project is jointly supported by NSF and the Chinese Academy of Sciences and the National Natural Science Foundation of China.