构建宽窄带隙同型异质结构的双层薄膜是提高透明导电薄膜光电性能的新思路。采用基于密度泛函的第一性原理，对本征和掺杂SnO2/SnSe2的电子结构、光学性质、载流子迁移率、电荷分布、能带排列进行计算。结果表明：本征和掺杂SnO2/SnSe2电子结构内部存在的电势差会使体系内部的电子向着界面处或SnSe2处转移，处于界面处的电子会在界面间隙内形成二维电子气并在界面处高速移动，从而提高了载流子的迁移率，而处于SnSe2处的电子由于没有杂质离子散射的影响迁移率也相应提高，4种不同掺杂类型异质结构的载流子迁移率分别为772.82、5 286.04、2 656.90 m2/(S·V)和17 724.60 m2/(S·V)，光学透过率在80%以上。

It is important to improve its electrical and optical performances of transparent conductive thin films via constructing a double-layer homogeneous heterostructure with a wide and narrow band gap. The electronic structure, optical properties, carrier mobility, charge distribution, and energy band alignment of intrinsic and doped SnO2/SnSe2 were calculated using the first-principles based on density functionalities. The results show that a potential difference existing in the intrinsic and doped SnO2/SnSe2 electronic structures causes the electrons in the system to transfer to the interface or SnSe2, and the electrons at the interface form a two-dimensional electron gas (2-DEG) in the interface gap and move at a high speed at the interface, thereby increasing the mobility of carriers, while the electrons at SnSe2 have a corresponding increase in mobility due to the absence of impurity ion scattering. The mobilities are 772.82, 5 286.04, 2 656.90 m2/(S·V) and 17 724.60 m2/(S·V), respectively, and the optical transmittance is >80%.