不同氟源对FTO薄膜性能影响及其作用机理

Effect of Different Fluorine Sources on Properties of the FTO Films and Its Mechanism of Action

以SnCl_4·5H_2O为锡源,以不同氟的化合物如CF_3COOH,HF和SnF_2为氟源,采用溶胶-凝胶-蒸镀法制备不同氟源掺杂的SnO_2(Fluorine-doped Tin Oxide,FTO)薄膜,主要研究CF_3COOH,HF和SnF_2不同氟源的掺入对薄膜的表面形貌、结构以及光电性能的影响,系统地探讨了其作用机制。结果表明:3种氟源制备的FTO薄膜表面形貌分别为不规则多边形状、棒状以及金字塔状,且均呈四方金红石型结构。3种氟源中,以SnF_2为氟源的SnO_2薄膜综合性能较佳,其方块电阻为14.7Ω/,红外反射率为86.1%。不同氟源的掺杂机制主要是F-和SnO2晶粒间的键合方式不同,或生成氟锡化合物的难易程度不同,一次掺杂的氟源(SnF_2)制备的FTO薄膜性能优于二次掺杂的(HF)以及间接性掺杂的氟源(CF_3COOH)。

Fluorine-doped tin oxide(FTO)films were deposited onto glass substrates by the sol-gel-evaporation method with SnCl 4·5H 2O as a tin source,and CF 3COOH,HF or SnF 2 as a fluorine source,respectively.The effect of different fluorine sources on the surface morphology,structure and photoelectric properties of SnO 2 thin films was investigated,and the mechanism of the impact on properties of FTO film was systematically discussed.The results show that all the particles in the FTO films present a tetragonal rutile phase.The surface morphologies of the FTO films correspond to irregular polygonal shape,rod-shaped and pyramid-shaped for fluorine sources CF 3COOH,HF and SnF 2.For the optimized sample the values of sheet resistance and IR reflectivity are 14.7Ω/□and 86.1%,respectively.The doping mechanism of three different fluorine sources is the different bonding forms between F ion and the growing SnO 2 grains,or is different in forming tin fluorine compound.The performance of FTO films prepared by one time doping SnF 2 is superior to secondary doping HF and indirect doping fluorine source CF 3COOH.