【摘要】 采用微机械剥离法得到横向尺寸为10μm的碲化锗(GeTe)纳米片.通过电子束曝光和真空溅射镀膜的方法,以钛金合金为接触电极,制备基于二维碲化锗(2D-GeTe)纳米材料的场效应晶体管(FET),并测定了其电学性能.结果表明,剥离所得GeTe纳米材料具有良好的结晶性,光学带隙为1.98 eV,属于p型半导体;该场效应晶体管展现出了6.4 cm2·V-1·s-1的载流子迁移率和670的开关电流比的良好电学性能.更多还原

【Abstract】 Compared with three-dimensional(3 D)materials,two-dimensional(2 D)materials have excellent photoelectric properties,and can be used in many fields such as electronics and photocatalysis,etc. Two-dimensional germanium telluride(2 D-GeTe)belongs to a narrow-band gap semiconductor,and its carrier mobility has a theoretical value of up to 1066.33 cm2·V-1·s-1,but its crystal structure limits its application in the field of optoelectronics. In this work,a GeTe alloy was synthesized by a high-temperature sintering method in a tube furnace,and then a GeTe nanosheet with a lateral dimension about 10 μm successfully was prepared by micromechanical exfoliation. After heat-treating the material,through the method of electron beam exposure and vacuum sputtering coating,using titanium(10 nm)/gold(60 nm)alloy as the contact electrode,the 2 DGeTe based field effect transistor(FET)was prepared,and the electrical properties were measured at room temperature. The results show that the GeTe nanomaterials obtained by exfoliating have good crystallinity,a wide optical absorption range,and an optical band gap of 1.98 eV,which belongs to p-type semiconductors.At the same time,the FET devices prepared based on 2 D-GeTe exhibits favorable electrical properties,with a channel length of 7 μm,a channel width of 3 μm,and a carrier mobility of 6.4 cm2·V-1·s-1,the switching current ratio is 670. And the output curve is non-linear,which indicates that due to the preparation process and the environment,there is a clear Schottky barrier between the material and the contact electrode. In short,the study of 2 D-GeTe electrical properties and the successful preparation of FET devices have enriched the types of two-dimensional materials in the field of semiconductor optoelectronic devices,and provide some reference and guidance for the research of high optoelectronic devices.更多还原