PROGRESS WITH LUMINESCENCE IMAGING FOR THE CHARACTERISATION OF SILICON WAFERS AND SOLAR CELLS

Electroluminescence (EL) and photoluminescence (PL) imaging have recently been demonstrated to be fast experimental techniques that allow measurement of the spatial distribution of the diffusion length in silicon solar cells and of the minority carrier lifetime in large area silicon wafers (1, 2). A practical advantage of these techniques is that data acquisition times for high resolution luminescence images are typically on the order of only one second. This paper reviews previous work related to process monitoring by luminescence imaging techniques and discusses some recent progress in the areas of several experimental and theoretical aspects of luminescence imaging. It is shown that luminescence imaging is an exceptionally versatile tool that provides spatially resolved information about a variety of material and solar cell parameters with data acquisition times that are compatible with in-line process monitoring.