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We demonstrate photon-counting single-pixel imaging in the ultraviolet region. Toward this target, we develop a high-performance compact single-photon detector based on a 4H-SiC single-photon avalanche diode (SPAD), where a tailored readout circuit with active hold-off time is designed to restrain detector noise and operate the SPAD in the free-running mode. We use structured illumination to reconstruct 192 × 192 compressed images at a 4 fps frame rate. To show the superior capability of ultraviolet characteristics, we use our single-pixel imaging system to identify and distinguish different transparent objects under low-intensity irradiation and image ultraviolet light sources. The results provide a practical solution for general ultraviolet imaging applications. [ABSTRACT FROM AUTHOR]

In order to reduce the noise of traditional silicon pixel detectors, a new type of low-capacitance silicon pixel detector with three floating electrodes is proposed in this paper, which reduces the cathode area while keeping the volume unchanged. A TCAD simulator is used to simulate the electrical performance of the detector and obtain electrical characteristics including depletion voltage, capacitance, and leakage current. According to the results of simulation and calculation, compared with the traditional silicon pixel detector with the same volume, the capacitance of the detector without floating electrodes was reduced by 68%, the capacitance of the detector with three floating electrodes was reduced by 68%, and the leakage current was reduced by two orders of magnitude. [ABSTRACT FROM AUTHOR]

In this study, a novel three-dimensional trench detector structure was proposed. The detector structure includes trench electrodes and columnar electrodes. The columnar electrodes are distributed in the middle, the middle of the sides, and the four corners of the cross section of the substrate. A cross-shaped electrode is etched from top to bottom, and a polygonal trench electrode is etched from bottom to top; the bottom of the cross-shaped electrode abuts the top of the polygonal electrode. Electrical characteristics of the novel detector are simulated by Technology Computer Aided Design simulation, and we can obtain that this design reduces the area of the bottom low electric field, optimizes the electric field, and reduces the mutual interference between the cells. [ABSTRACT FROM AUTHOR]

Interactions between neighboring cells often occur in a semiconductor silicon detector array. That is, there are high-energy particles incident on one cell of the detector that generate an electric signal for the cell, while weak signals are also generated in other neighboring cells. Therefore, isolation of the detector cells is an important factor in the performance of the detector, particularly for its energy resolution. To eliminate the dead space in the 3D-trench-electrode detector proposed by Brookhaven National Laboratory, a novel three-dimensional (3D) detector, the 3D-Open-Shell-Electrode Detector (3DOSED), was proposed in 2018, in which good isolation between cells was achieved. To verify this and determine the optimal structure design, a Silvaco technology computer-aided design simulation tool was used to simulate the electrical characteristics of the detector in 3D. The distributions of the electric field and the weighting field of 3DOSEDs were obtained with different opening gap angles. A single minimum ionizing particle was used that was incident vertically on the middle of the central collection electrode and peripheral trench electrode of the detector cell, according to the Ramo theorem of the principle of induced-current generation, and the mathematical software matlab was employed to calculate the induced current and carrier drift time. The interference current between the neighboring cells of a 3DOSED was obtained. Good isolation was found between neighboring cells in the 3DOSED. [ABSTRACT FROM AUTHOR]

Presents a study which described the fabrication and performance of a type of solid-state hydrogen detector. Method of the study; Results and discussion; Conclusion.