Applications of synchrotron radiation X-ray techniques on the analysis of the behavior of transition metals in solar cells and single-crystalline silicon with extended defects

Abstract

A high flux, non-destructive X-ray synchrotron-based technique, X-ray fluorescence microscopy (μ-XRF), is able to detect metal precipitates as small as a few tens of nanometers in diameter within a silicon matrix, with micron-scale spatial resolution. When this technique is combined with the X-ray beam-induced current (XBIC) technique, one can acquire, in situ, complementary information about the elemental nature of transition metal precipitates and their recombination activity. Additionally, X-ray absorption microspectroscopy (μ-XAS) analyses yield information about the local environment of the impurity atoms and their chemical state. Model defect structures and photovoltaic-grade multicrystalline silicon (mc-Si) were studied using these techniques, and the effect of transition metal clusters on the electrical properties of good and bad regions of mc-Si are discussed in detail.