Spatially resolved assessment of power losses due to bulk material quality and metallization problems

The main advantage of Illuminated Lock-In Thermography (ILIT) over standard (Dark) Lock-In Thermography is the ability to measure at actual operation conditions of solar cells. Thus ILIT allows a quantitative and spatially resolved investigation of the sum of all power losses in a solar cell at actual operation conditions with one measurement. The quantitative influence of low bulk material quality on solar cell performance is investigated. Also the locations of high contact resistance of the frontside metalization and of high series resistance within the metalization were determined with ILIT. The results were compared with Corescan results for the same cells and a good correlation between the locations determined with both methods was found.