Doped Layer Characterization Using Accurate Optical Modelling of Mid-Infrared Spectrometry

Formation of doped layers such as emitter or back surface field is one of the crucial steps in solar cell manufacturing. Characterization of these doped layers using infrared spectrometry is a faster and non-destructive replacement of the conventional methods but require in-depth understanding of the free carrier absorption and optical scattering parameters in the mid-infrared range. This work demonstrates an optical model capable of accurately describing the infrared reflectance and transmittance of samples with different surface morphologies and doped layers. This will be useful in predicting various doped layer properties such as sheet resistance, surface concentration and doped layer depth.