2D semiconductors like Molybdenum disulfide (MoS₂) still have issues in forming good metal electrode (Schottky and Ohmic) especially for mono layer (ML) to few layers thick due to strain and metallization issues. Here, we explore a 2D semi-metal, titanium disulfide (TiS₂), for making different types of contacts with ML MoS₂ using density functional theory (DFT). It is observed that ML TiS₂ induces ML MoS₂ to become p-type with a doping density of 3.85 × 10¹⁷ cm⁻³ which becomes larger with thicker TiS₂. Thus, TiS₂ can thus be utilized as a variable contact material ohmic if the MoS₂ is p-type and as Schottky if the MoS₂ is n-type with a Schottky barrier height ranging from 0.3 to 1.35 eV. One of the important results from the study is that compared to a traditional metal–MoS₂ in a TiS₂–MoS₂ contact the bandgap is preserved where in contrast, a traditional metal contact metalizes the monolayer MoS₂ and fill its bandgap with states. Hence, a clear path forward to make pristine contacts is to use 2D semi-metals in conjunction with 2D semiconductors.

诸如二硫化钼（MoS ₂）的2D半导体在形成良好的金属电极（肖特基和欧姆）方面仍然存在问题，尤其是由于应变和金属化问题，对于单层（ML）到几层厚的电极。在这里，我们探索二维半金属二硫化钛（TiS ₂），使用密度泛函理论（DFT）与ML MoS ₂进行不同类型的接触。观察到，ML TiS ₂引起ML MoS ₂变成p型，掺杂密度为3.85×10 ¹⁷  cm ^-3，而TiS ₂越厚，掺杂密度越大。因此，如果MoS ₂可以将TiS ₂用作可变接触材料欧姆如果MoS ₂为n型且肖特基势垒高度范围为0.3到1.35 eV，则p为p型，肖特基为Schottky 。该研究的重要结果之一是，与TiS ₂ -MoS ₂接触中的传统金属MoS ₂相比，能带隙得以保留，相比之下，传统金属接触使单层MoS ₂金属化并用态填充其带隙。因此，实现原始接触的明确途径是将2D半金属与2D半导体结合使用。