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We report a new method for large-scale production of GaMnN nanobars, by ammoniating Ga2O3 films doped with Mn under flowing ammonia atmosphere at 1000oC. The Mn-doped GaN sword-like nanobars are a single-crystal hexagonal structure, containing Mn up to 5.43 atom%. Thickness is about 100 nm and with a width of 200-400 nm. The nanobars are characterized by x-ray diffraction, scanning electron microscopy, x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy and photoluminescence. The GaN nanobars show two emission bands with a well-defined PL peak at 388 nm and 409 nm respectively. The large distinct redshift (409 nm) are comparable to pure GaN(370 nm) at room temperature. The red-shift photoluminescence is due to Mn doping. The growth mechanism of crystalline GaN nanobars is discussed briefly. 相似文献
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利用Pd催化合成单晶GaN纳米线的光学特性(英文) 总被引:1,自引:0,他引:1
基于金属元素钯具有的催化特性,采用射频磁控溅射方法,在Si(111)衬底上沉积Pd:Ga2O3薄膜,然后在950℃下对薄膜进行氨化,制备出大量GaN纳米线.采用扫描电子显微镜(SEM)、X射线衍射(XRD)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)等技术手段对样品的结构、形貌和成分进行分析.结果表明,制备的样品为具有六方纤锌矿结构的单晶GaN纳米线,直径在20-60nm范围内,长度为几十微米,表面光滑无杂质,结晶质量较高.用光致发光光谱对样品的发光特性进行测试,分别在361.1、388.6和426.3nm处出现三个发光峰,且与GaN体材料相比近带边紫外发光峰发生了较弱的蓝移.对GaN纳米线的生长机制也进行了简单的讨论. 相似文献
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首先分析了粗糙集理论中现在常用的属性依赖性度量中的不合理性,然后结合概率统计中的卡方分布的思想,给出一种新的属性依赖性度量,根据这种依赖性度量,给出属性重要性的定义,最后详细讨论了它们的性质. 相似文献
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