Short-circuit capacitance of illuminated solar cells

Abstract

The recently observed short‐circuit capacitance of illuminated photovoltaic solar cells has been attributed to injection of minority carriers into the base by the perfectly shorted n‐p junction, a result incompatible with conventional junction theory. In the present letter, this capacitance is treated as the result of voltage modulation of the space‐charge width and subsequent redistribution of the minority carriers in the base, all in the context of conventional junction theory. Comparison with experimental results shows that this model gives the correct magnitude of the effect and predicts the dependence on spectral distribution of the illumination and the circuit test frequency.