Photodiodes and junction field-effect transistors with high UV sensitivity

Silicon photodiodes and photo-FET´s with high blue and UV sensitivity have been produced by a special boron diffusion process. Diodes with a junction depth around 0.2 µm exhibit a responsivity of 0.1 A/W at 253 nm; the maximum responsivity (with a quantum efficiency close to 100 percent) is reached at 440 nm. The responsivity of the photo-FET´s operating in the photoconductive mode (VGS= 0) exceeds 10³A/W at 350 nm. The spectral response curve and the large-signal behavior of the photo-FET´s are strongly dependent on the operating conditions.