Semiconductor detection apparatus capable of switching capacitance among different levels, and detection system including the apparatus

Abstract

A detection apparatus includes a transistor disposed on a substrate, a conversion element disposed above the transistor and connected to the transistor, a capacitor connected in parallel with conversion element to the transistor, the capacitor including, between the substrate and the conversion element, an ohmic contact part connected to the conversion element, a semiconductor part connected to the ohmic contact part, and an electrically conductive part disposed at a location opposite to the semiconductor part and the ohmic contact part via an insulating layer, and a potential supplying unit configured to selectively supply a first electric potential to the electrically conductive part to accumulate charge carriers in the semiconductor part and a second electric potential to the electrically conductive part to deplete the semiconductor part. The detection apparatus configured in the above-described manner is capable of controlling pixel capacitance thereby achieving a high signal-to-noise ratio.