Accelerated ageing of a-SiC:H/c-Si photovoltaic heterostructures

Photovoltaic heterostructures composed of thin film of p-doped amorphous silicon carbide a-SiC and thin films of n-doped crystalline silicon prepared by PECVD deposition technique were the object of this study. Prepared structures have been subjected to accelerated aging process at 85 °C in dry air, respectively under the influence of the different degrees of humidity. The electrical measurements and visual assessments of the samples were performed before the process of accelerated aging and after 25, resp. 90 days. Accelerated aging affects the electrical transport processes in the solar heterostructures. Slight increase in leakage resistance and capacity of the sample was detected in the case of dry heat. The effect of a 100 % humidity resulted in deteriorated performance of the sample. The destruction of the sample was observed in the case of sample immersed in the water. The complex impedance formalism and equivalent circuit were used to estimate the aging influences.