Mapping the Local Photoelectronic Properties of Polycrystalline Solar Cells Through High Resolution Laser-Beam-Induced Current Microscopy

Abstract—To boost the efficiency of thin-film polycrystalline so-lar cells that are microscopically inhomogeneous, it is imperative to understand how the grain interiors (GIs) and grain boundaries (GBs) within these materials affect its overall electronic proper-ties. By using an apertured near-field scanning optical microscope in an illumination mode, we determined the local photocurrent that is generated within the GIs and at the GBs with nanoscale resolution and correlate the results with surface morphology and composition. Index Terms—Cadmium compounds, current measurement, grain boundaries (GBs), photovoltaic (PV) cells, scanning probe microscopy, thin-film devices, wavelength measurement. I