单层硫化钼(MoS2)因具有直接带隙和特殊的六方晶系层状结构,而呈现优异的光学特性和电学特性。基于p-n结扩散模型推导了MoS2/Si异质结的接触特性和伏安特性,分析了不同施主掺杂浓度(n-MoS2)和受主掺杂浓度(p-Si)对能带结构和输运特性的影响。研究表明:MoS2/Si异质结的内建电势和势垒区宽度由施主、受主掺杂浓度共同决定。随着掺杂浓度的升高,内建电势VD逐渐增大,而势垒区宽度XD呈明显减小的趋势。另外,发现p-Si的受主掺杂浓度决定了MoS2/Si异质结的电流密度和反向饱和电流密度,均随着p-Si的受主掺杂浓度的增大而减小,但与n-MoS2的掺杂浓度关系不大。
Single-layer(SL) molybdenum disulfide(Mo S2) has excellent optical and electrical properties for its special hexagonal layered structure and the direct band gap. In this paper, we investigated the contact characteristics and the cur-rent-voltage characteristics of n-Mo S2/p-Si heterojunction based on the p-n junction diffusing model, and analyzed the effects of the doping concentrations of n-Mo S2 and p-Si on the band structure and transport properties. The results indicate that both the built-in potential and the width of the space-charge region depend on the doping concentrations. The built-in potential is positively related to them while the width of the space-charge region declines sharply with the in-creasing of them. In addition, we found that the current density decreases with the increasing of the doping concentration of p-Si, and significantly increases with the increasing of the temperature, but has not much to do with that of n-Mo S2.These results are instructive for fabricating Mo S2 optoelectronic devices.