Abstract: A semiconductor-based radiation detector comprising a semiconductor substrate and an amorphous semiconductor layer formed on one surface of the substrate, one electrode being applied to the substrate and one to the amorphous layer, the electrodes formed on the amorphous semiconductor layer consisting of closely spaced, interconnected conductive strips which are substantially uniformly arranged over the entire radiation-incident surface of the amorphous semiconductor layer whereby the electrostatic capacitance appearing between the electrodes of the detector is significantly reduced without significantly changing the area of the detector that responds to radiation.

Abstract: In the typical embodiments of the invention described in the specification, a radiation detector has a single crystal silicon substrate coated with an amorphous semiconductor film containing silicon and carbon, metal electrodes being provided. Amorphous layers are formed by a plasma CVD method using mixtures of monosilane gas and acetylene or tetrafluorocarbon gas at a pressure of 10 Torr with an applied voltage of 400-800 volts providing increased band gaps and higher resistivity to reduce current leakage.

Abstract: In the representative radiation detectors described in the specification, an amorphous silicon layer is grown on one or both of the opposed electrode surfaces of a single crystal silicon substrate and the amorphous silicon layer extends to the side surface of the substrate. The corresponding electrode is deposited on the amorphous silicon layer. Detectors may also be made using a single crystal of Ge, GeAs or CdTe with an amorphous layer of the same or another semiconductor material.

Abstract: In the specific embodiments described in the specification, a semiconductor radiation detector has a single-crystal silicon substrate coated with an amorphous silicon film containing an impurity to widen the mobility band gap of the semiconductor to reduce the reverse bias leakage current. Phosphorus and carbon are disclosed as impurities for the amorphous silicon film.