溅射气压对氧化镓薄膜光学特性的影响

Effect of Sputtering Pressure on Optical Properties of Ga2O3 Films Prepared by RF Magnetron Sputtering

摘要:

采用射频磁控溅射法在石英衬底上制备了氧化镓(Ga₂O₃)薄膜。利用X射线衍射仪和紫外-可见-红外分光光度计分别对Ga₂O₃薄膜的晶体结构和光学带隙进行了表征,并在室温下测量了Ga₂O₃薄膜的光致发光(PL)谱。结果表明:制备的Ga₂O₃薄膜呈非晶态。吸收边随着溅射气压的增加先蓝移后红移,光学带隙值范围为5.06~5.37eV,溅射气压为1Pa时,制备的Ga₂O₃薄膜具有最大的光学带隙。在325nm激光激发下,400nm附近和525nm附近处出现与缺陷能级相关的发光峰。

Abstract:

Ga₂O₃ thin films were grown on quartz substrate by radio-frequency magnetron sputtering. The structure and optical bandgap of Ga₂O₃ films were characterized by X-ray diffraction and UV-Vis-IR spectroscopy, respectively. The photoluminescence (PL) spectra of Ga₂O₃ films were measured at room temperature. The results show that the deposited Ga₂O₃ films are amorphous. As the pressure increases, the optical absorption edge firstly shows blue shift and then switches to red shift. The optical bandgap value ranges from 4.96 to 5.30eV. When the sputtering pressure is 1Pa, the deposited Ga₂O₃ film has the largest optical band gap. Under the excitation of 325nm laser, luminescence peaks related to defect energy levels appear near 400 and 525nm.