Mg掺杂浓度对Mg_xZn_(1-x)O薄膜结构和光学性能的影响

Influence of Mg Doping Concentration on Structure and Optical Properties of Mg_xZn_(1-x)O Thin Films

通过超声喷雾热解工艺在p型<100>Si衬底上制备了不同Mg掺杂浓度的纳米MgxZn1-xO薄膜。通过扫描电镜(SEM)、X射线光电子能谱(XPS)、X射线衍射(XRD)和光致发光(PL)谱的测试对不同Mg掺杂浓度下薄膜的表面形貌、成分、晶体结构和光学性能进行了研究。SEM测试结果表明,低Mg掺杂浓度时,MgxZn1-xO表面平整致密,但随Mg浓度的增加,薄膜表面平整度降低。XRD测试结果表明在低浓度下MgxZn1-xO薄膜是ZnO的纤锌矿结构,而没有出现MgO的分相,ZnO的衍射峰峰强随Mg浓度的增加逐渐减弱。不同Mg掺杂浓度下的光致发光谱图均出现了近带边紫外发射峰和可见光发射峰,其中近带边紫外发射峰随掺杂浓度的增大出现了明显的蓝移。

MgxZn1-xO thin films with different Mg doping concentrations were fabricated on p-type Si substrates using ultrasonic spray pyrolysis technology.The morphologies,component,crystal structures and optical properties were investigated by scanning electro micro-scopy（SEM）,X-ray diffraction（XRD） and photoluminescence（PL）,respectively.The results indicated that the surface of MgxZn1-xO films with low Mg concentrations was flat and compact,and the roughness of films increased as the Mg concentrations increasing.The low Mg concentration MgxZn1-xO film was wurtzite structure and the MgO phase was absent.The diffraction peak intensity of ZnO decreased as the Mg concentration increasing,near band energy peaks and deep-level defect peaks appeared in all samples,and the near band energy peaks had a distinct blue shift as Mg concentration increasing.