1T’-MoTe_2原位生长关键工艺技术

Key Technology of 1T'-MoTe_2 In-Situ Growth

二元过渡金属硫族化合物碲化钼(MoTe_2),由于其室温下合适的禁带宽度和较高的理论迁移率,将作为沟道材料应用于下一代集成电路器件中,而受到普遍的关注。通过碲(Te)和钼(Mo)的原位固相反应,在真空环境中不同温度条件下退火得到1T’-MoTe_2薄膜。利用喇曼光谱、X射线光电子能谱分析以及椭圆偏振光谱化对制备的MoTe_2薄膜进行表征分析,研究了不同退火温度对MoTe_2薄膜质量的影响。实验表明,在450℃退火条件下,薄膜喇曼峰强高,半峰宽较窄,结晶质量良好。但是,由于高温下单质和化合态Te的再蒸发效应,当退火温度从450℃上升到600℃时,薄膜喇曼峰强明显减小且半峰宽变宽,结晶质量显著变差。

Because of a higher theoretical mobility and an appropriate band gap at room temperature,binary transition metal dichalcogenide molybdenum ditelluride（ MoTe_2） has attracted widespread attention,as it is an excellent candidate for the channel material in next-generation integrated circuit devices. By in-situ solid state reaction of Te and Mo,1T＇-MoTe_2 thin films were fabricated at different annealing temperatures in vacuum. The MoTe_2 thin film was investigated by Raman spectra,X-ray photoelectron spectroscopy analysis and spectroscopic ellipsometry. And the effects of different annealing temperatures on the quality of MoTe_2 thin films were studied. The results show that at the annealing temperature of 450 ℃,the Raman intensity is strong and FWHM is narrow,and the crystal quality of the film is good. However,when the annealing temperature increases from 450 ℃ to 600 ℃,due to the largely enhanced reevaporation effect both in elemental and chemical state of Te,the crystal quality of the films deteriorates,as the Raman intensity becomes weakened and FWHM becomes broader.