The role of antireflective coatings in silicon solar cells - the influence on their electrical parameters

In this work, the authors compared the properties of multicrystalline silicon solar cells which depended on the kind of following antireflective layers: a-Si:C:H, a-Si:N:H and TiOx. Current voltage characteristics for multicrystalline silicon solar cells were measured by the use of a computer controlled global spectrum sun simulator under an AM 1.5. The measurements of I-V characteristics allow the determination of basic electrical parameters and efficiency using the double exponential relationship from a two-diode solar cells model. Two key parameters: refractive index and thickness of the film affect the final features of the antireflective coating. Optimisation of these parameters and afterwards the experimental verification lead to the minimalisation of the reflection coefficient that decides about the quality of the antireflective layer. A high quality reflective layer can improve the efficiency of the solar cell even by 30%.