Tm掺杂AlN薄膜结构及其光致发光特性研究

A Study of Tm-doped AlN Thin Films Structure and Photoluminescence Properties

利用射频磁控反应溅射方法,以Al-Tm合金为靶材,Si(100)为衬底,制备了铕(Tm)掺杂的氮化铝(AlN)薄膜.利用X-射线衍射仪(XRD)和原子力显微镜(AFM)研究了退火温度对样品结晶形态和表面粗糙度的影响.XRD测试结果表明,经高温退火处理后的样品具有良好的(100)择优取向;AFM测试表明,适当温度退火后的薄膜更加致密、平整;X-射线能量谱(EDS)测试表明,薄膜主要组分为Al、N、O、和C元素,但C、O主要吸附于薄膜表面,Al和N的含量接近于AlN的化学计量比;光致发光光谱(PL)测试表明,Tm掺杂的AlN薄膜发光中心位于468nn,对应于可见光谱中的蓝色光,退火温度对发光强度有重要影响.

Tm-doped AIN thin films have been deposited on Si（100） substrate by using radio frequency reactive magnetron sputtering system with as A1-Tm alloy target. The effects of annealing-temperature on the crystalline structure and surface morphology of the films was investigated by X-ray diffraction （XRD） and atomic force microscopy （AFM）. The annealed films shows an excellent preferred orientation of （100） and surface roughness can be improved by a suitable annealing. The compositions of the films were characterized by EDS. EDS data show that A1, N, C and O elements exist in the A1N films, while C and O elements mainly exist on surface. Moreover, the films present a composition highly close to A1N stoichiometric. The photolumi- nescenee （PL） spectra shows that the characteristic emission band of Tm-doped AIN is at 468 nm, which is correspond to blue light in the visible light spectra. Moreover, the PL intensity at 468 nm is seriously affected by annealing temperature.