High-Speed and Ultrasensitive Solar-Blind Ultraviolet Photodetectors Based on Grown β-GaO Single-Crystal Films.

Deep-level defects in β-GaO that worsen the response speed and dark current () of photodetectors (PDs) have been a long-standing issue for its application. Herein, an grown single-crystal GaO nanoparticle seed layer (NPSL) was used to shorten the response time and reduce the of metal-semiconductor-metal (MSM) PDs. With the NPSL, the was reduced by 4 magnitudes from 0.

Growth-Promoting Mechanism of Bismuth-Doped Cu(In,Ga)Se Solar Cells Fabricated at 400 °C.

The classical high-temperature synthesis process of Cu(In,Ga)Se (CIGS) solar cells limits their applications on high-temperature intolerant substrates. In this study, a novel low-temperature (400 °C) fabrication strategy of CIGS solar cells is reported using the bismuth (Bi)-doping method, and its growth-promoting mechanism is systematically studied. Different concentrations of Bi are incorporated into pure chalcopyrite quaternary target sputtered-CIGS films by controlling the thickness of the Bi layer.

Significantly Enhancing Response Speed of Self-Powered CuZnSn(S,Se) Thin Film Photodetectors by Atomic Layer Deposition of Simultaneous Electron Blocking and Electrode Protective AlO Layers.

Kesterite CuZnSn(S,Se) (CZTSSe) thin film is a promising material for optoelectronic devices. In this work, we fabricate Mo/CZTSSe/CdS/ZnO/ITO (ITO, indium tin oxide) heterojunction photodetectors with favorable self-powered characteristics. The photodetector exhibits exceptional high-frequency photoresponse performance whose -3 dB bandwidth and rise/decay time have reached 1 MHz and 240/340 ns, respectively.

Significantly Enhanced Detectivity of CIGS Broadband High-Speed Photodetectors by Grain Size Control and ALD-AlO Interfacial-Layer Modification.

The Cu(In,Ga)Se (CIGS) thin film has been commercialized as solar cells with great success, but its application for photodetectors still faces some practical challenges, including low detectivity and long response time. In this paper, the structure of the Mo/CIGS/CdS/ZnO/ITO heterojunction has been fabricated, and satisfactory performances of high detectivity and fast response time have been achieved by suppressing the dark current and enhancing the carrier mobility. The controllable growth of CIGS grains is accomplished through optimizing the selenization process, demonstrating that bigger grain sizes resulted in higher carrier mobility and better response characteristics.