Thin-Film Photovoltaic Reliability and Lifetime Assessment
PI: Chad S, Karach
Thin-film photovoltaics (PV) have been an emerging technology in the area of solar research development. Solar cells based on thin-film PVs are fabricated in layered structures, much like meltgrown solar cells. The commercial use of thin film photovoltaics would necessitate the analysis and testing of residual stresses and defects within the structure. The stresses can adversely affect reliability of thin-film solar cells due to interfacial delamination of film layers and defects can lead to decreased performance and reliability due to stress concentrations which can lead to fatigue crack growth, Using a nanoscratching approach that is on the same order as the film thickness (100nm - 20m) the residual stresses in the films and fracture toughness can be determined. The technique is fast and minimally invasive and can potentially provide results at high though-puts. The technology will lead to a technique that is used in production facilities for residual stress analysis and improve quality control and thin-film solar cell reliability. Potentially this technology may be applied in the field to existing solar cells to determine realtime life prediction of components.