We examined the oxygen adsorption effect on the electric property of the field-effect transistor with an atomic layer MoS channel, whose experiment was executed in well-defined ultra-high vacuum conditions and with surface treatment. The threshold voltage change of the - curve with the oxygen partial pressure shows -type doping in the low-pressure range and -type doping in the high-pressure range. In this report, the V vs. oxygen partial pressure uptake curve is well modeled with the Langmuir type adsorption/desorption. The deduced adsorption energy indicates that the adsorbed species are oxygen atoms on the pristine MoS, suggesting a catalytic behavior of MoS for the oxygen reduction reaction. The oxygen adsorption at the S vacant site induces the initial -type doping. DFT calculation illustrates that, despite the electron transfer from the substrate to the oxygen molecule, the electronic structure change causes the -type doping.

中文翻译：

---

多层MoS2场效应晶体管上氧气分压的n型和p型掺杂切换

我们研究了氧吸附对具有原子层MoS通道的场效应晶体管电性能的影响，该实验是在明确的超高真空条件和表面处理下进行的。阈值电压随氧分压的变化曲线在低压范围内呈现β型掺杂，在高压范围内呈现β型掺杂。在本报告中，V 与氧分压吸收曲线通过 Langmuir 型吸附/解吸进行了很好的建模。推导出的吸附能表明，吸附物质是原始 MoS2 上的氧原子，这表明 MoS2 对氧还原反应具有催化行为。 S空位处的氧吸附引起初始-型掺杂。 DFT计算表明，尽管电子从衬底转移到氧分子，但电子结构的变化导致了β型掺杂。