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Characterisation of silicon samples for photovoltaic applications using luminescence based methods has evolved rapidly over the last ten years.Particularly the development of Photoluminescence (PL) imaging enables a number of novel material characterisation and quality control methods in small scale R&D applications and also in large scale production.Given the contactless and non-destructive nature of PL inspection,the short measurement time and the rich information contained in spatially resolved data,the range of applications spans a wide range of material-and electrical device parameters for samples from the entire value chain,including silicon bricks,as cut wafers,partially processed wafers and fully processed cells.Some representative examples will be discussed in this paper.We will review recent progress that has been made with the analysis of silicon bricks and the extraction of spatially resolved bulk lifetime information from PL intensity ratios.Another particularly promising application for PL imaging is the inspection of as cut silicon wafers for quality control in wafer and cell manufacturing.Capturing high resolution PL images,combined with sophisticated image analysis algorithms allows efficiency limiting defects to be detected and associated metrics to be extracted.These metrics,detected on the as-cut wafer,have been shown to correlate strongly with final cell performance.Representative trial data from medium and large scale trials will be discussed.PL imaging is also well established now for characterisation of fully processed cells.For example,the extraction of spatially resolved series resistance data from luminescence images taken under a range of operating conditions has been widely adopted as a fast method for device development and process troubleshooting.Here,we will present proof of concept data for a new method to measure qualitative series resistance variations within a solar cell in a contactless manner and"on the fly",i.e.with the cell in constant motion at 250 mm/s belt speed.