Mg掺杂GaN纳米线的结构及其特性

利用类似Delta掺杂技术在硅衬底上沉积Mg:Ga2O3薄膜, 然后在850 ℃下对薄膜进行氨化, 反应后制备出大量Mg掺杂GaN纳米线. 采用扫描电子显微镜(SEM)、X射线衍射(XRD)、傅里叶变换红外(FTIR)光谱和高分辨透射电子显微镜(HRTEM)对样品进行分析.结果表明, Mg掺杂GaN纳米线具有六方纤锌矿单晶结构, 纳米线的直径在30-50 nm范围内, 长度为几十微米.     

Fabrication and Characterization of Mg-Doped GaN Nanowires

Mg-doped GaN nanowires have been synthesized by ammoniating Ga2O3 films doped with Mg under flowing ammonia atmosphere at 850℃. The Mg-doped GaN nanowires are characterized by x-ray diffraction （XRD）, scanning electron microscope （SEM）, high-resolution transmission electron microscopy （HRTEM） and photoluminescence （PL）. The results demonstrate that the nanowires are single crystalline with hexagonal wurzite structure. The diameters of the nanowires are 20-30nto and the lengths are 50-100μm. The GaN nanowires show three emission bands with well-defined PL peak at 3.45 eV, 3.26 eV, 2.95 eV, respectively. The large distinct blueshift of the bandgap emission can be attributed to the Burstein-Moss effect. The peak at 3.26 eV represents the transition from the conduction-band edge to the acceptor level AM （acceptor Mg）. The growth mechanism of crystalline GaN nanowires is discussed briefly.