On the characterisation of solar cells using light beam induced current measurements

The Light Beam Induced Current (LBIC) measurement technique is used to perform localized characterization on solar cells using a light beam as a probe. This technique allows the determination of the local photo-response of a solar cell which enables characterization of the spatial distribution of defects and electrical parameters. By scanning the beam probe across a solar cell while measuring the current-voltage characteristics at each point, a map of various cell parameters such as short-circuit current, carrier lifetime, quantum efficiency of a solar cell and other device parameters may be extracted using this technique. In this study a high resolution LBIC system was designed and constructed. This paper discusses the design of the LBIC system, the software interfacing of the data acquisition system, local photo-response of the individual cells and LBIC maps indicating areas of reduced efficiency or performance as a function of spatial distribution within different solar cell technologies, including, single-crystalline (c-Si) and multicrystalline (mc-Si) Silicon. In addition this paper also discusses the basic principle of the parameter extraction algorithm used to extract device parameters of a solar cell.