Evaluation of silicon, organic, and perovskite solar cell reliability with low-frequency noise spectroscopy

Low-frequency noise spectroscopy has been used to evaluate the recombination, the transport processes and their implications to device performance of several photovoltaic technologies under temperature or radiation stress. Investigating the polymer: fullerene solar cell, the observed differences in charge carrier lifetime and mobility, detected by the noise spectra, have been attributed to a different film ordering and donor-acceptor phase segregation in the active layer. In order to explain the origin of random current fluctuations observed in silicon solar cells, a theoretical model that combines the trapping/detrapping and the recombination mechanisms has been formulated. By applying this theoretical framework to the perovskite solar cells, the low-temperature phase transition between the orthorhombic and tetragonal structure has been evidenced by the temperature evolution of the noise amplitude. A relation between the size of the perovskite grains, the energy disorder of the defect states, the noise level, and the device parameters has been demonstrated.