A photomultiplier containing a solid-state photoconductive film composed of amorphous selenium (a-Se) is provided. In the a-Se containing photomultiplier, a hole-blocking layer is provided that maximizes gain and maintains low dark conductivity. Also, the hole-blocking layer achieves reliable and repeatable impact ionization without irreversible breakdown. The hole-blocking layer is a non-insulating metal oxide having a dielectric constant (k) of greater than 10.

Methods and devices for detecting incident radiation, such as incident X-rays or gamma-rays, are provided. The methods and devices use single-crystalline mercury chalcoiodide compounds having the formula Hg.sub.3Q.sub.2I.sub.2, where Q represents a chalcogen atom or a combination of chalcogen atoms, as photoelectric materials. Also provided are methods for growing single-crystals of the mercury chalcoiodide compounds using external organic chemical transport agents.

Methods and devices for detecting incident radiation are provided. The methods and devices use high quality single-crystals of photoactive semiconductor compounds in combination with metal anodes and metal cathodes that provide for enhanced photodetector performance.

Disclosed herein is an apparatus and a method of making the apparatus. The method comprises obtaining a plurality of semiconductor single crystal chunks. Each of the plurality of semiconductor single crystal chunks may have a first surface and a second surface. The second surface may be opposite to the first surface. The method may further comprise bonding the plurality of semiconductor single crystal chunks by respective first surfaces to a first semiconductor wafer. The plurality of semiconductor single crystal chunks forming a radiation absorption layer. The method may further comprise forming a plurality of electrodes on respective second surfaces of each of the plurality of semiconductor single crystal chunks, depositing pillars on each of the plurality of semiconductor single crystal chunks and bonding the plurality of semiconductor single crystal chunks to a second semiconductor wafer by the pillars.

A flat panel detector includes a base substrate, a sensing electrode and a bias electrode over the base substrate, and an insulating layer over the sensing electrode and the bias electrode at a side distal from the substrate. A difference between thicknesses of regions of the insulating layer corresponding to the sensing electrode and the bias electrode respectively is not greater than a preset threshold. When a sufficiently high voltage is applied to the insulating layer and turned on, because the thickness thereof is relatively uniform, a dark current generated by the sensing electrode and the bias electrode under the insulating layer is relatively uniform, thereby improving detection accuracy of the flat panel detector.

Provided is a radiation detection element, including: a plurality of electrode portions on a surface of a substrate; and an insulating portion between the electrode portions, the substrate being made of a compound semiconductor crystal containing cadmium telluride or cadmium zinc telluride, wherein an intermediate layer containing tellurium oxide is present between each of the electrode portions and the substrate, and wherein the tellurium oxide layer has a thickness of 100 nm or less on a 500 nm inner side from an end portion of the insulating portion between the electrode portions. The radiation detection element has higher adhesion of the electrodes, and does not result in an element performance defect caused by insufficient insulation between the electrodes, even if the radiation detection element has a narrower distance between the electrode portions in order to obtain a high-definition radiographic image.

A radiation sensor includes a radiation-sensitive semiconductor layer, a cathode electrode disposed over a front side of the radiation-sensitive semiconductor layer that is configured to be exposed to radiation, at least one anode electrode disposed over a backside of the radiation-sensitive semiconductor layer, and a potential barrier layer located between the cathode electrode and the front side of the radiation-sensitive semiconductor layer.

The present embodiment relates to a radiation detector having a structure enabling suppression of polarization in a thallium bromide crystalline body and suppression of corrosion of an electrode in the air. The radiation detector comprises a first electrode, a second electrode, and a thallium bromide crystalline body provided between the first and second electrodes. One of the first and the second electrodes includes an alloy layer and a low-resistance metal layer provide on the alloy layer. The alloy layer is comprised of an alloy of metallic thallium and another metal different from the metallic thallium. The low-resistance metal layer has a resistance value lower than a resistance value of the alloy layer and is electrically connected to a pad on a readout circuit while the radiation detector is mounted on the readout circuit.

Provided is a field shaping multi-well photomultiplier and method for fabrication thereof. The photomultiplier includes a field-shaping multi-well avalanche detector, including a lower insulator, an a-Se photoconductive layer and an upper insulator. The a-Se photoconductive layer is positioned between the lower insulator and the upper insulator. A light interaction region, an avalanche region, and a collection region are provided along a length of the photomultiplier, and the light interaction region and the collection region are positioned on opposite sides of the avalanche region.

A radiation sensor includes a radiation-sensitive semiconductor layer, a cathode electrode disposed over a front side of the radiation-sensitive semiconductor layer that is configured to be exposed to radiation, at least one anode electrode disposed over a backside of the radiation-sensitive semiconductor layer, and a potential barrier layer located between the cathode electrode and the front side of the radiation-sensitive semiconductor layer.