溅射功率对MgZnO薄膜晶体管性能的影响

Effect of sputtering power on properties of MgZnO thin film transistors

本文通过射频磁控溅射的方法在Si衬底上制备了MgZnO薄膜晶体管,研究不同溅射功率对MgZnO薄膜晶体管电学和薄膜性能的影响,对制备的器件采用Keysight B 1500 A型号的半导体参数仪测试其电学性能,通过公式计算分析电学参数.利用原子力显微镜(AFM)和描电子显微镜(SEM)对薄膜表面形貌进行探测.实验结果表明,不同溅射功率对MgZnO薄膜晶体管的性能有影响,当Mg靶溅射功率为3 W时,器件电学性能以及薄膜质量最佳,电流开关比为1.54×10^(7),阈值电压为24 V,亚阈值摆幅为1.1 V/decade,界面缺陷态密度为3.82×10^(12) cm^(-2)·eV^(-1),所占的的原子百分比(at.%)分别为1.54,MgZnO薄膜的均方根粗糙度(RMS)为1.168 nm,粗糙度数值最低.

In this paper,MgZnO thin film transistors were fabricated on Si substrates by radio frequency magnetron sputtering.The influence of different sputtering powers on the electrical properties of MgZnO thin film transistors was studied.The prepared devices were tested by Keysight B1500A semiconductor parameter instrument.Its electrical properties are calculated and analyzed through formulas.Atomic Force Microscope(AFM)and Scanning Electron Microscope(SEM)are used to detect the surface morphology of the films.The experimental results show that different sputtering powers have an impact on the performance of MgZnO thin film transistors.When the Mg target sputtering power is 3W,the electrical performance and film quality of the device are the best,the current switching ratio is 1.54×10^(7),the threshold voltage is 24V,The subthreshold swing is 1.1V/decade,the interface defect state density is 3.82×10^(12) cm^(-2)·eV^(-1),and the atomic percentage(at.%)is 1.54 respectively.The root mean square roughness(RMS)of the MgZnO film is 1.168nm,the roughness value is the lowest.