Analysis of light propagation in thin-film solar cells by dual-probe scanning near-field optical microscopy

In this study, light propagation in textured hydrogenated microcrystalline silicon (μc-Si:H) thin-film solar cells is investigated on a sub-micron-scale by means of dual-probe scanning near-field optical microscopy (SNOM). Applying advanced modes of operation - exclusively available at dual probe SNOMs - light propagation is analyzed with subwavelength resolution. Measurements at μc-Si:H thin-film solar cells layer are presented visualizing the influence of local surface features on light propagation. Furthermore, the intensity decay of light guided inside the solar cell is mapped. The observed intensity decay agrees well with theory, verifying the validity of the method.