有源层厚度对Li-ZTO TFT电学性能的影响

Effect of sputtering time on the electrical properties of Li-ZTO TFT

本研究旨在制备Li-ZTO单有源层薄膜晶体管,并研究有源层厚度对其性能的影响。该研究采用磁控溅射方法,使用Li-ZTO靶材制备出了有源层厚度分别为70 nm,90 nm,110 nm的器件。采用了X射线光电子能谱(XPS)、原子粒显微镜(AFM)、X射线衍射仪(XRD)等设备对制备出的Li-ZTO薄膜进行测试分析。通过对不同有源层厚度的薄膜物质组成、表面形貌、晶粒生长情况的测试分析,进一步研究了有源层厚度对Li-ZTO薄膜性能的影响。除此之外,我们还利用半导体参数仪对Li-ZTO的电学性能进行了测试。结果表明,过厚的有源层将影响电荷传输,增加散射中心,影响器件性能。因此,有源层厚度为70 nm的Li-ZTO具有最好的性能,包括12.33 cm^(2)/vs的饱和迁移率、0.66 V的阈值电压、2.12 V/dec的亚阈值摆幅以及>10~8的开关比。

The aim of this study is to prepare Li-ZTO single active layer thin film transistors and to investigate the effect of active layer thickness on their performance.The devices with active layer thicknesses of 70 nm,90 nm and 110nm were prepared by magnetron sputtering using Li-ZTO targets.To test and analyze the prepared Li-ZTO films,X-ray photoelectron spectroscopy(XPS),atomic particle microscopy(AFM)and X-ray diffractometer(XRD)were used.The influence of the active layer thickness on the properties of Li-ZTO films was further investigated by testing and analyzing the material composition,surface morphology and grain growth of the films with different active layer thicknesses.In addition,the electrical properties of Li-ZTO were also tested using a semiconductor parameter meter.The results show that too thick active layer will affect the charge transport,increase the scattering center and affect the device performance.Therefore,the Li-ZTO with an active layer thickness of 70 nm has the best performance,including a saturation mobility of 12.33cm 2/vs,a threshold voltage of 0.66 V,a subthreshold swing of 2.12 V/dec,and a switching ratio of>108.