Photodiode with increased UV and blue light sensitivity - has pn-junction in form of buried layer connected to one electrode

摘要

The photodiode consists of a semiconductor body with two electrodes, between which is formed a pn-junction. The latter is formed by a buried layer at small distance under the surface of the semiconductor body which is exposed to light. The buried layer is connected to one electrode (I). The junction region between the buried layer and the electrode (I) is more strongly doped. Typically the semiconductor body is of n-doped silicon. Its doping pref. amounts to 5 X 1014 to 5 x 1015 cm-3. Pref. The buried layer contains boron atoms with a surface concn. between 1012 and 1015 cm-2. The surface may be coated with a passivating anti-reflection film.