Large area LBIC measurement system for thin film photovoltaic modules

A laser beam induced current system has been developed for large area thin film technology. Employing a non-destructive laser scanning approach, such a system is used as a characterisation tool that is able to perform local performance investigation and allows efficient defect detection in large scale devices. In this paper, the results are shown for large area single junction amorphous silicon modules. The scanning images reveal an inhomogeneous current signal. Cross-section analysis illustrates that in some modules, there is considerable performance variation between cells. Certain cells are nearly or completely inactive. Interconnection problems, tiny cracks and defects that cannot be detected by visual inspection can also be identified.