Determination of band alignment at two-dimensional MoS2/Si van der Waals heterojunction
Determination of band alignment at two-dimensional MoS2/Si van der Waals heterojunction
复制标题
DOI：
10.1063/1.5030557
复制
发表时间：
2018-06
影响因子：
3.2
通讯作者：
Neeraj Goel;Rahul Kumar;Monu Mishra;Govind Gupta;Mahesh Kumar
中科院分区：
文献类型：
--
作者：
Neeraj Goel;Rahul Kumar;Monu Mishra;Govind Gupta;Mahesh Kumar
为了理解在MoS 2-硅界面处发生的不同机制，我们通过在硅衬底上剥离MoS 2来制造MoS 2/Si异质结。拉曼光谱和原子力显微镜（AFM）测量暴露了沉积的MoS 2薄片中的少层特征。在此，已经广泛地研究了MoS 2/Si异质结处的能垒和载流子密度的温度依赖性。此外，为了研究MoS 2/Si界面处的能带对准，我们使用X射线和紫外光电子能谱计算了0.66 ± 0.17 eV的价带偏移和0.42 ± 0.17 eV的导带偏移。我们确定了一个II型带对齐的接口，这是非常有利于光激发载流子的运输。作为一个概念验证的应用程序，我们扩展我们的MoS 2/Si异质结的光伏行为的分析。本工作不仅提供了MoS 2/p-Si和MoS 2/n-Si异质结之间的比较研究，而且为将来MoS 2与Si的集成设计界面特性铺平了道路。为了理解MoS 2-Si界面发生的不同机制，我们通过在硅衬底上剥离MoS 2来制备MoS 2/Si异质结。拉曼光谱和原子力显微镜（AFM）测量暴露了沉积的二硫化钼薄片中的几层的签名。在此，已经广泛地研究了MoS 2/Si异质结处的能垒和载流子密度的温度依赖性。此外，为了研究MoS 2/Si界面处的能带对准，我们使用X射线和紫外光电子能谱计算了0.66 ± 0.17 eV的价带偏移和0.42 ± 0.17 eV的导带偏移。我们确定了一个II型带对齐的接口，这是非常有利于光激发载流子的运输。作为一个概念验证的应用程序，我们扩展我们的MoS 2/Si异质结的光伏行为的分析。本工作不仅对MoS_2/p-Si和MoS_2/n-Si异质结进行了比较研究，而且还对MoS_2/p-Si异质结的结构进行了分析。
To understand the different mechanism occurring at the MoS2-silicon interface, we have fabricated a MoS2/Si heterojunction by exfoliating MoS2 on top of the silicon substrate. Raman spectroscopy and atomic force microscopy (AFM) measurement expose the signature of few-layers in the deposited MoS2 flake. Herein, the temperature dependence of the energy barrier and carrier density at the MoS2/Si heterojunction has been extensively investigated. Furthermore, to study band alignment at the MoS2/Si interface, we have calculated a valence band offset of 0.66 ± 0.17 eV and a conduction band offset of 0.42 ± 0.17 eV using X-ray and Ultraviolet photoelectron spectroscopy. We determined a type-II band alignment at the interface which is very conducive for the transport of photoexcited carriers. As a proof-of-concept application, we extend our analysis of the photovoltaic behavior of the MoS2/Si heterojunction. This work provides not only a comparative study between MoS2/p-Si and MoS2/n-Si heterojunctions but also paves the way to engineer the properties of the interface for the future integration of MoS2 with silicon.To understand the different mechanism occurring at the MoS2-silicon interface, we have fabricated a MoS2/Si heterojunction by exfoliating MoS2 on top of the silicon substrate. Raman spectroscopy and atomic force microscopy (AFM) measurement expose the signature of few-layers in the deposited MoS2 flake. Herein, the temperature dependence of the energy barrier and carrier density at the MoS2/Si heterojunction has been extensively investigated. Furthermore, to study band alignment at the MoS2/Si interface, we have calculated a valence band offset of 0.66 ± 0.17 eV and a conduction band offset of 0.42 ± 0.17 eV using X-ray and Ultraviolet photoelectron spectroscopy. We determined a type-II band alignment at the interface which is very conducive for the transport of photoexcited carriers. As a proof-of-concept application, we extend our analysis of the photovoltaic behavior of the MoS2/Si heterojunction. This work provides not only a comparative study between MoS2/p-Si and MoS2/n-Si heterojunctions but al...