Undoped ZnO nanostructures were deposited on Si (100) substrate using direct-current-unbalanced magnetron sputtering. The nanostructure modification of conelike into rod-shaped nanocolumnars is found after thermal annealing with O2. This modification transforms paramagnetism into room-temperature ferromagnetism, induced by Zn vacancy enhancement at the cost of O vacancies. First principles confirm that the ferromagnetism comes from O 2p holes due to Zn vacancies. Our result shows the crucial role of ZnO nanostructure modification in inducing ferromagnetism for novel functional device applications.

中文翻译：

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通过ZnO纳米结构改性增强Zn空位诱导的室温铁磁性

使用直流非平衡磁控溅射将未掺杂的 ZnO 纳米结构沉积在 Si (100) 衬底上。用 O2 热退火后发现锥形纳米结构转变为棒状纳米柱。这种修饰将顺磁性转化为室温铁磁性，这是由 Zn 空位增强引起的，以 O 空位为代价。第一性原理证实铁磁性来自于锌空位引起的 O 2p 空穴。我们的结果显示了 ZnO 纳米结构改性在为新型功能器件应用诱导铁磁性方面的关键作用。