摘要
目前二维IV-VI族窄带隙半导体材料在存储开关、太阳能转换、热电转换和近红外光电器件等领域受到了广泛关注.其中硒化锡(SnSe)和二硒化锡(SnSe2)作为典型的IV-VI族窄带隙半导体,由于其优异的电子和光电性能成了研究热点.目前,制备SnSe和SnSe_2薄膜通常需要使用两套气相沉积系统,而制备SnSe_2纳米片更是需要通过化学气相沉积的方法才能获得,因此面临制备成本高、可控性低的问题.该文提供了一种气相沉积方法,一步制备了SnSe和SnSe_2薄膜,大大提高了制备效率.该方法只需要控制加热温度,制备过程简单可控.通过一系列的表征手段证明,制备的SnSe薄膜和SnSe_2薄膜十分纯净.
Two-dimensional layered IV-VI narrow bandgap semiconductors have attracted great interests for applications in memory switching devices,solar energy conversion,thermoelectric energy conversion,and near-infrared optoelectronic devices.SnSe and SnSe_2 as typical two-dimensional layered IV-VI narrow bandgap semiconductors,have been widely investigated due to their excellent electronic and photoelectric properties.Currently,two separative deposition systems are required to prepare both SnSe and SnSe_2 films,while SnSe_2 films can only be obtained by chemical vapor deposition,which increases the preparation cost and reduces the controllability.In this paper,we grow SnSe and SnSe_2 thin films in one process,which greatly improves the conversion rate.We show that the as-deposited samples are pure SnSe films and SnSe_2 films through a series of characterization methods.
引文
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