National Laboratory of Solid-State Microstructures, Collaborative Innovation Center of Advanced Microstructures, and School of Electronic Science and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China.
Nano Lett. 2022 Aug 24;22(16):6671-6677. doi: 10.1021/acs.nanolett.2c02023. Epub 2022 Aug 3.
Layered two-dimensional dichalcogenides are potential candidates for post-silicon electronics. Here, we report insightfully experimental and theoretical studies on the fundamental Coulomb screening and scattering effects in these correlated systems, in response to the changes of three crucial Coulomb factors, including electric permittivity, interaction distance, and density of Coulomb impurities. We systematically collect and analyze the trends of electron mobility with respect to the above factors, realized by synergic modulations on channel thicknesses and gating modes in dual-gated MoS transistors with asymmetric dielectric cleanliness. Strict configurative form factors are developed to capture the subtle parametric changes across dimensional crossover. A full diagram of the carrier scattering mechanisms, in particular on the pronounced Coulomb scattering, is unfolded. Moreover, we clarify the presence of up to 40% discrepancy in mobility by considering the permittivity modification across dimensional crossover. The understanding is useful for exploiting atomically thin body transistors for advanced electronics.
层状二维二硫化物是后硅电子学的潜在候选材料。在这里，我们报告了对这些相关系统中基本库仑屏蔽和散射效应的深入实验和理论研究，以响应三个关键库仑因素（包括介电常数、相互作用距离和库仑杂质密度）的变化。我们通过协同调制具有不对称介电清洁度的双栅 MoS 晶体管的沟道厚度和栅极模式，系统地收集和分析了电子迁移率与上述因素的关系，实现了这一点。我们开发了严格的组态因子来捕捉跨维度交叉时细微的参数变化。展开了载流子散射机制的全图，特别是在明显的库仑散射方面。此外，我们通过考虑跨维度交叉时的介电常数变化，阐明了迁移率存在高达 40%的差异。这一理解对于利用原子层厚体晶体管实现先进电子学是有用的。
