Wafer‐scale fabrication of edge-contacted nanosheet transistors via alloying-mediated phase engineering

Abstract

Edge contacts offer significant potential for scaling down 2D transistors due to their minimal contact resistance and reduced contact length. However, their intricate fabrication complicates reproducible large-scale production and evaluation of electrical properties, particularly for p-type channels. Here, the waferscale production of p-type nanosheet transistors with pure edge contacts by leveraging the alloying-mediated phase engineering of 2D MoTe2 is demonstrated. The relative 1T’-phase stability of WxMo1xTe2 facilitates the one-pot growth of lateral polymorphic junctions by combining the 2H-single-crystalline MoTe2 channels with WxMo1xTe2 edge contacts. These edge-contact transistors exhibit improved carrier transfer, which is attributed to the impurity-free contact interface and suppressed metal-induced gap states. Consequently, their electrical performance is both exceptional and reproducible, compared with that of transistors fabricated using two-step metallization. Furthermore, irrespective of contact length scaling (8–15 nm), the contact resistivity remains consistently low (5.9 107 Ω cm2) owing to edge-confined transport, providing a promising ultra-scaled contact scheme for Ångström-node 2D integrated circuits.