Fully integrated blue/UV SOI CMOS photosensor for biomedical and environmental applications

In this paper, we present a microsystem for measuring optical power in blue/UV wavelengths (from lambda = 200 nm to lambda = 450 nm) which includes a photodiode and the analog processing circuit of the photodiode signal, fully integrated in 2 mu m SOI CMOS technology. The photodiode has a maximum responsivity for lambda = 400 nm. Th photosensor functions as a current to frequency converter. Measurements of the microsystem illuminated by blue and UV LEDs demonstrate the good linear behavior, sensitivity and efficiency of the system.