Spectral Dependence of Nonlinearity for Silicon Photodiodes

The nonlinearities of two silicon photodiodes (Si PDs) in visible and infrared light were experimentally measured in an optical power range from nanowatts to milliwatts. Spectral supralinearities for a Si PD were clearly observed in visible and infrared visible light. This resulted from a decrease in the recombination loss of the generated photocurrent ratio in the silicon-bulk region or the interface between the Si bulk and the silicon dioxide. These experimentally measured results are adequate for correcting the responsivity of Si PDs in a wide optical power range and predicting the spectral supralinear behaviours.