Interface Capture Effect Printing Atomic-Thick 2D Semiconductor Thin Films

Adv Mater. 2022 Dec;34(49):e2207392. doi: 10.1002/adma.202207392. Epub 2022 Oct 26.

Abstract

2D semiconductor crystals offer the opportunity to further extend Moore's law to the atomic scale. For practical and low-cost electronic applications, directly printing devices on substrates is advantageous compared to conventional microfabrication techniques that utilize expensive photolithography, etching, and vacuum-metallization processes. However, the currently printed 2D transistors are plagued by unsatisfactory electrical performance, thick semiconductor layers, and low device density. Herein, a facile and scalable 2D semiconductor printing strategy is demonstrated utilizing the interface capture effect and hyperdispersed 2D nanosheet ink to fabricate high-quality and atomic-thick semiconductor thin-film arrays without additional surfactants. Printed robust thin-film transistors using 2D semiconductors (e.g., MoS2 ) and 2D conductive electrodes (e.g., graphene) exhibit high electrical performance, including a carrier mobility of up to 6.7 cm2 V-1 s-1 and an on/off ratio of 2 × 106 at 25 °C. As a proof of concept, 2D transistors are printed with a density of ≈47 000 devices per square centimeter. In addition, this method can be applied to many other 2D materials, such as NbSe2 , Bi2 Se3 , and black phosphorus, for printing diverse high-quality thin films. Thus, the strategy of printable 2D thin-film transistors provides a scalable pathway for the facile manufacturing of high-performance electronics at an affordable cost.

Keywords: 2D materials; direct-writing; printing; transistors.