Hyperspectral laser beam induced current system for solar cell characterization

We introduce a novel hyperspectral laser beam induced current (LBIC) system that uses a supercontinuum laser that can be tuned from 400nm - 1200nm with diffracted limited spot size. The solar cell is light biased while simultaneously being illuminated by a chopped laser beam at a given wavelength. Current-voltage measurements performed by measuring the current perturbation due to the laser using a lock-in amplifier allow us to extract performance metrics at a specific lateral position and depth (by tuning the wavelength of the laser) while the device is at operating conditions. These parameters are simultaneously compared to material deformations as determined from the doping density, and the built-in voltage. Concurrently we also probe lateral recombination variation by measuring the activation energy thereby providing a comprehensive and unique analysis.