溶胶水热法制备FTO纳米晶体薄膜及其电学性能研究

Electrical Properties of FTO Nanocrystalline Thin Film Fabricated by Sol Hydrothermal Method

以SnCl2·2H2O和HF为前驱体,采用溶胶水热法成功制备掺氟的SnO2纳米晶体薄膜,以研究氟掺杂对其半导体性能和电学性能的影响。采用XRD,SEM,DTA-TG,IR,霍尔效应测试仪等手段分别进行测试,分析F/Sn比对其性能的影响,获得低表面电阻薄膜的制备条件。结果表明SnO2晶体随着烧结温度的升高发生改变,当温度在450℃,热处理时间为30 min,生成金红石晶型,并且在此温度下,F原子可以有效地掺杂。F掺杂明显的降低了薄膜的电阻率,有效的提高了薄膜的载流子浓度和迁移率。并且在氟锡摩尔比F/Sn为3∶10时,晶体薄膜表面方块电阻最低,为35Ω/□,载流子浓度为2.8×1016/cm3,迁移率为31 cm2/V·s。

The collosol of tin oxide doped with F based on SnCl2·2H2O and HF as the precursor material was prepared by the sol-gel method. The thin film was developed through hydrothermal process. The influence of the fluorine doping on the semiconductor properties and electrical properties were studied. The factors which influence the performance and obtain the best preparation conditions for the lowest sheet resistance were analyzed. The nanostructure and properties were characterized by X-ray diffraction（ XRD）,scanning electron microscope（ SEM）,differential thermal analysis and thermal gravity（ DTA-TG）,infrared radiation（ IR）,respectively. The electrical properties were tested by Hall effect measurement system. The results show that the tin oxide doped with fluorine film exhibits excellent performance. Compared with the pure tin oxide nanocrystals,the fluorine doped tin oxide nanocrystals exhibit a higher conductivity. When the molar proportion of F /Sn is about 3 /10,the calcination temperature is 450 ℃ and the calcination time is 30 min,the sheet resistance of fluorine doped film is 35 Ω /□,the carrier concentration is 2. 8 × 10^16/cm^3 and the carrier mobility is 31 cm^2/V·s.