Effect of nonuniform illumination on the photovoltaic decay characteristic of solar cells

In the present study, the distributed parameter analysis of a solar cell has been made using the photovoltage decay (PVD) method to investigate passible mechanisms responsible for the discrepancies between the experimental results and models reported earlier regarding open-circuit voltage decay (OCVD). The analysis has been performed accounting for the effects of cell area and sheet resistivity of the diffused layer under nonuniform illumination assuming ideal line source of broad length. The expressions for physical parameters-surface-voltage and surface-current density caused by the concentration gradient of the generated carriers due to nonuniform illumination--have been obtained. The variational behavior of these parameters along the direction of the intensity variation in the junction plane has also been evaluated. The decay behavior of open-circuit voltage influenced by surface voltage has been compared with experimental results reported by other workers and is found qualitatively in excellent agreement.