Triply degenerate semimetal PtBi₂ as van der Waals contact interlayer in two-dimensional transistor

Abstract

The low-energy electronic excitations in topological semimetal yield a plethora of a range of novel physical properties. As a relatively scarce branch, the research of triple degenerate semi-metal is mostly confined to the stage of physical properties and theoretical analysis, there are still challenges in its practical application. This research showcases the first application of the triply degenerate semimetal PtBi2 in electronic devices. Leveraging a van der Waals transfer method, PtBi2 flakes were used as interlayer contacts for metal electrodes and WS2 in transistors. The transistor achieved a switching ratio above 106 and average mobility can reach 85 cm2V-1s-1, meeting integrated circuit requirements. Notably, the excellent air stability of PtBi2 simplifies the device preparation process and provides more stable device performance. Transfer process reduces the Schottky barrier between metal electrodes and semiconductors while avoiding Fermi pinning during metal deposition to achieve excellent contact. This groundbreaking work demonstrates the practical applicability of PtBi2 in the field of electronic devices while opening new avenues for the integration of novel materials in semiconductor technology, setting a precedent for future innovations.

Abundant Catalytic Edge Sites in Few-Layer Horizontally Aligned MoS2 Nanosheets Grown by Space-Confined Chemical Vapor Deposition

“…For applications in nanoelectronics [43] and optoelectronics [44], the horizontal orientation of molecular layers is often preferred due to the need for high crystallinity (very low defect density) and large surface areas. However, this configuration tends to make the surface of these 2D materials catalytically inactive, as only the sulfur atoms along their edges exhibit significant catalytic activity [45].…”