Real-time determination of EVA crosslinking with Raman spectroscopy during photovoltaic manufacturing

ChemPhotovoltaic manufacturers are under increasing pressure to improve quality and reduce cost. One important process and quality parameter is the degree of crosslinking in the ethylene vinyl acetate (EVA) material used as the solar cell embedding material which supports and protects the solar cells. Currently available methods of measuring EVA crosslinking are not capable of real-time in-line measurement due to slow speed, the need to extract samples, and a lack of consistency and precision. Tornado’s HyperFlux™ spectrometer was deployed for Raman analysis to determine the degree of curing of ethylene vinyl acetate (EVA) in a photovoltaic module manufacturing line and was shown to have enough sensitivity and speed to be an effective tool for real-time, in-line quality control and process optimization.