Curved or spherical X‐ray sources are significant for use in intraoperative radiotherapy, adaptive static medical imaging, and high‐throughput industrial inspection, but they are hard to achieve using traditional thermionic cathode point electron sources. In this study, copper (Cu)‐doped zinc oxide (ZnO) nanowires grown on a brass substrate with a designed shape are proposed to achieve cold cathode hemispherical X‐ray sources. The strain‐driven solid–liquid growth model of Cu‐doped ZnO nanowires is proposed, and the oxidation temperature‐dependent and time‐dependent growth characteristics are investigated to optimize the morphologies of ZnO nanowire cold cathodes with a typical turn‐on field of 7.36 MV m−1, a maximum current of 12.54 mA (4.93 mA cm−2) and a uniform field emission image with an area of 2.54 cm2. Hemispherical X‐ray sources formed by Cu‐doped ZnO nanowire field emitters grown on spherical brass alloy and an Al thin film transmission anode target deposited on a hemispherical quartz glass are successfully fabricated, achieving an operating voltage of 39 kV, a dose rate of 240 µGyair s−1 and a projection X‐ray imaging resolution of 2.8 lp mm−1, demonstrating their promising use in a variety of applications.

中文翻译：

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ZnO 纳米线冷阴极半球形 X 射线源


弯曲或球形 X 射线源对于术中放疗、自适应静态医学成像和高通量工业检查具有重要意义，但使用传统的热离子阴极点电子源很难实现。在这项研究中，提出了在具有设计形状的黄铜衬底上生长的铜 （Cu） 掺杂氧化锌 （ZnO） 纳米线，以实现冷阴极半球形 X 射线源。提出了铜掺杂 ZnO 纳米线的应变驱动固液生长模型，并研究了氧化温度依赖性和时间依赖性生长特性，以优化 ZnO 纳米线冷阴极的形态，典型导通场为 7.36 MV m-1，最大电流为 12.54 mA （4.93 mA cm-2），均匀场发射图像面积为 2.54 cm2。成功制造了由在球形黄铜合金上生长的铜掺杂 ZnO 纳米线场发射器和沉积在半球石英玻璃上的铝薄膜传输阳极靶形成的半球形 X 射线源，实现了 39 kV 的工作电压、240 μGyair s-1 的剂量率和 2.8 lp mm-1 的投影 X 射线成像分辨率， 展示了它们在各种应用中的前景。