While two-dimensional (2D) materials have emerged as a new platform for nanoelectronic devices with improved electronic, optical, and thermal properties, and their heightened sensitivity to electrostatic and mechanical interactions with their environment has proved to be a bottleneck. Few-layer (FL) 2D devices retain the desirable thinness of their monolayer cousins while boosting carrier mobility. Here, we employ an electrothermal model to study FL field-effect devices made from transition metal dichalcogenides MoS₂ and WSe₂ and examine the effect of both electrical and thermal interlayer resistances, as well as the thermal boundary resistance to the substrate, on device performance. We show that overall conductance improves with increasing thickness (number of layers) at small gate voltages, but exhibits a peak for large gate voltages. Joule heating impacts performance due to relatively poor thermal conductance to the substrate and this impact, along with the location of the hot spot in the FL stack, varies with carrier screening length of the material. We conclude that coupled electrothermal simulation can be employed to design FL 2D devices with improved performance.

尽管二维（2D）材料已成为具有改进的电子，光学和热特性的纳米电子设备的新平台，但事实证明，它们对与环境之间的静电和机械相互作用的高度敏感性已成为瓶颈。少数层（FL）2D器件在提高载流子迁移率的同时，仍保留了其单层表亲的理想厚度。在这里，我们采用电热模型研究由过渡金属_二卤化物MoS ₂和WSe ₂制成的FL场效应器件并检查电和热层间电阻以及对基板的热边界电阻对器件性能的影响。我们表明，在较小的栅极电压下，总电导随厚度（层数）的增加而提高，但在较大的栅极电压下表现出峰值。焦耳加热会由于相对较差的基材导热性而影响性能，并且这种影响以及FL堆栈中热点的位置随材料的载流子筛选长度而变化。我们得出的结论是，可以采用耦合电热仿真来设计具有改进性能的FL 2D器件。