Experimental validation of nonlinearity suppression for an inverse-layer-type silicon photodiode and its prediction based on theoretical modeling

The spectral nonlinearity of an inverse-layer-type silicon (Si) photodiode (PD) in the visible region was investigated. As expected by theoretical calculation, supralinearity and saturation of the Si PD, which are key factors of nonlinearity, were suppressed by applying a reverse voltage above 30 V. Experimentally observed nonlinear behavior depending on the reverse bias was compared to a theoretical model describing supralinearity, including the inner parameters of the Si PD, and these comparison results were in agreement. This theoretical model enables us to quantitatively predict the behavior of the supralinearity of the inverse-layer-type Si PD in various reverse bias conditions. Accurate experimental nonlinearity supported by theoretical predictions will contribute to high-accuracy optical measurement with the Si PD over a wide range of optical power levels and various reverse-bias voltages.