Two different approaches, which permitted rapid photoluminescence imaging of dislocation-related D1, and band-to-band radiation on multicrystalline solar cell wafers at room temperature, were reported. A new light-emitting diode-based method was compared with the recently introduced pulsed laser based method. Using both techniques, spatially resolved images were obtained from 15.6cm x 15.6cm wafers; originating from various stages of the standard solar cell production process. This showed that these techniques were highly useful for in-line quality control. Both methods provided homogeneous illumination over the whole sample area. With a resolution of around 300μm, and a total recording time of ∼45s, full D1 images could be captured by using the new diode technique. The most promising aspect was that surface artefacts did not lead to any noticeable disturbance of the D1 image. For acid-textured wafers, the pulsed laser based method was clearly better than the continuous diode technique.

Novel Imaging Techniques for Dislocation-Related D1-Photo-Luminescence of Multicrystalline Si Wafers – Two Different Approaches. R.P.Schmid, D.Mankovics, T.Arguirov, T.Mchedlidze, M.Kittler: Physica Status Solidi C, 2011, 8[4], 1297–301