Spectral and spatially resolved imaging of photoluminescence in multicrystalline silicon wafers

Abstract

The photoluminescent properties of multicrystalline silicon wafers have been studied using hyperspectral imaging in the region 900–1700 nm. Hyperspectral imaging provides high resolution macroscopic images in both the spatial and spectral dimensions over a time frame of seconds. Energy states introduced in the bandgap of Si from crystal imperfections resulted in increased recombination of photogenerated free charge carriers. Spectral resolution in the near infrared enabled us to spatially image specific radiative recombination processes through traps in the Si bandgap. Hyperspectral imaging is a fast, non-contact, and non-destructive method, giving it potential for industrial applications.