Concept of photovoltaic transducer on a base of modified p–n junction solar cell

A concept of new photovoltaic transducer, combining properties of planar p–n solar cell and light-addressable potentiometric sensor (LAPS) is considered for chemical sensor application. The proposed photovoltaic transducer operation principle based on change of surface recombination velocity during gas adsorption. As compared with typical LAPS, the considered sensor has no reference electrode, it is not necessary to apply DC bias voltage and such sensor is applicable not only for liquid but for gas detection also. The influence of p–n junction depth, doping level, diffusion length on photocurrent of planar silicon junction for different value of surface recombination is studied by numerical simulation. It allows optimizing the junction parameters from point of view of its efficient application as a chemical sensor with photovoltaic transducer. The proposed chemical sensor concept was verified by LBIC method on modified industrial solar cell.