All-silicon photovoltaic detectors with deep ultraviolet selectivity

Abstract

AbstractFor a practical photodetector, fast switching speed and high on-off ratio are essential, and more importantly, the integration capability of the device finally determines its application level. In this work, the judiciously engineered Si3N4/Si detector with an open-circuit voltage of 0.41 V is fabricated by chemical vapor deposition methods, and exhibits good performance with repeatability. The advanced integration technology of Si3N4 and Si is the foundation for imaging functions in the near future. Compare to the current commercial Si p-i-n photodiodes, the detector cuts off the long-wavelength UV light over 260 nm, realizing the spectrum selectivity without filters or complexed accessories. The stability of this detector is further characterized by cycling response, temperature and light intensity dependence tests. In addition, we also analyze and explain the inherent mechanisms that govern the different operations of two types of Si3N4/Si photodetectors.