Molecular Approach to Engineer Two-Dimensional Devices for CMOS and beyond-CMOS Applications

Abstract

Two-dimensional materials (2DMs) have attracted tremendous research interest over the last two decades. Their unique optical, electronic, thermal and mechanical properties make 2DMs key building blocks for the fabrication of novel complementary metal-oxide-semiconductor (CMOS) and beyond-CMOS devices. Major advances in device functionality and performance have been made by the covalent or non-covalent functionalization of 2DMs with molecules: while the molecular coating of metal electrodes and dielectrics allows for more efficient charge injection and transport through the 2DMs, the combination of dynamic molecular systems, capable to respond to external stimuli, with 2DMs makes it possible to generate hybrid systems possessing new properties, by realizing stimuli-responsive functional devices thereby enabling functional diversification in More−than−Moore technologies. In this review, we first introduce emerging 2DMs, various classes of (macro)molecules, and molecular switches and discuss their relevant properties. We then turn to 2DM/molecule hybrid systems and the various physical and chemical strategies used to synthesize them. Next, we discuss the use of molecules and assemblies thereof to boost the performance of 2D transistors for CMOS applications and to impart diverse functionalities in beyond CMOS devices. Finally, we present the challenges, opportunities, and long-term perspectives in this technologically promising field. (OTS), 3-(trimethoxysilyl)-1-propanamine (APTMS), and trichloro(1H,1H,2H,2Hperfluorooctyl)silane (FOTS), respectively. (a-c) Reproduced with permission from ref ( 100 ).

Defect Engineering Strategies Toward Controlled Functionalization of Solution‐Processed Transition Metal Dichalcogenides

“…[ 17 ] Although the production methods already contribute to affect the quality and characteristics of solution‐processed TMDs (i.e., purity, aspect ratio), many research endeavors have also been devoted to the development of molecular strategies to meticulously tailor on demand their properties. [ 18,19 ] The physisorption and chemisorption of molecules and assemblies thereof onto 2D crystals are driven by a variety of mechanisms, whose versatility offers a powerful toolbox in such an exciting area of 2DM science. [ 20 ]…”

“…Above all, defects offer unique opportunities for functionalization strategies by molecular chemistry approaches, by acting as primary (re)active sites in 2DMs. [ 19,20 ]…”

“…[17] Although the production methods already contribute to affect the quality and characteristics of solution-processed TMDs (i.e., purity, aspect ratio), many research endeavors have also been devoted to the development of molecular strategies to meticulously tailor on demand their properties. [18,19] The physisorption and chemisorption of molecules and assemblies thereof onto 2D crystals are driven by a variety of mechanisms, whose versatility offers a powerful toolbox in such an exciting area of 2DM science. [20] DOI: 10.1002/smsc.202100122 Solution-processed transition metal dichalcogenides (TMDs) are attracting unceasing attention owing to their wide-ranging portfolio of physicochemical properties, making them prime candidates for low-cost and real-life applications in (opto)electronics, (bio)sensing, and energy-related technologies.…”

“…Above all, defects offer unique opportunities for functionalization strategies by molecular chemistry approaches, by acting as primary (re)active sites in 2DMs. [19,20] In this perspective, we review and highlight the recent seminal works on defect generation in TMDs, as well as the most enlightening and promising functionalization strategies taking advantage of their inherent defectiveness. Finally, we discuss the challenges and opportunities of defect engineering to produce hybrid multifunctional materials based on solution-processed TMDs, providing general guidelines to advance the knowledge toward novel technological breakthroughs.…”

Exchange Bias in Molecule/Fe3GeTe2 van der Waals Heterostructures via Spinterface Effects

“…[36][37][38][39] Indeed, hybrid heterostructures based on atomically sharp 2D material/molecule interfaces have been widely used to tailor the optoelectronic and transport properties of nonmagnetic layered materials. [40][41][42][43][44][45] However, so far the possibility to tune the properties of a layered magnetic material through the magnetic interactions at a van der Waals spinterface has not yet been experimentally demonstrated.Here, we report on the emergence of spinterface effects between molecular films of Co-phthalocyanine (CoPc) and a few-nm-thick FGT flakes. The molecular layer induces a negative magnetic exchange bias in FGT, indicating that the The exfoliation of layered magnetic materials generates atomically thin flakes characterized by an ultrahigh surface sensitivity, which makes their magnetic properties tunable via external stimuli, such as electrostatic gating and proximity effects.…”