Dislocation-related photoluminescence imaging of mc-Si wafers at room temperature

We report on a method for fast detection of defect rich areas in multicrystalline silicon solar wafers. It is based on photoluminescence imaging of the whole wafers and detects both the band-to-band radiation as well as the dislocation specific radiation D1. To illustrate the capabilities of the method we examined 5.0 × 5.0 cm2 wafer pieces in different stages of their processing. The achieved resolution of the D1 images was ∼120 μm, within a total recording time of 550 ms.