Metal–organic chemical vapor deposition of 2D van der Waals materials—The challenges and the extensive future opportunities

Abstract

The last decade has witnessed significant progress in two-dimensional van der Waals (2D vdW) materials research; however, a number of challenges remain for their practical applications. The most significant challenge for 2D vdW materials is the control of the early stages of nucleation and growth of the material on preferred surfaces to eventually create large grains with digital thickness controllability, which will enable their incorporation into high-performance electronic and optoelectronic devices. This Perspective discusses the technical challenges to be overcome in the metal–organic chemical vapor deposition (MOCVD) growth of 2D group 6 transition metal dichalcogenide (TMD) atomic crystals and their heterostructures, as well as future research aspects in vdW epitaxy for 2D TMDs via MOCVD. In addition, we encourage the traditional MOCVD community to apply their expertise in the field of “2D vdW materials,” which will continue to grow at an exponential rate.

Growth-Etch Metal–Organic Chemical Vapor Deposition Approach of WS2 Atomic Layers

“…Increasing the water flow rate enhances the re-evaporation of the a-C and thus the PL intensity increase. As mentioned above, based on the results summarized in Figures 1(a−c) and S2, as well as previous reports, 3,[16][17][18]32,48 there is a high nucleation density when using metal−organic precursors. The W(CO) 6 is known to thermally decompose at relatively low temperatures, 53 compared to the ones used here and needed for the growth of highly crystalline TMDCs.…”

“…This agrees well with reports on MOCVDgrown TMDC layers, where domain sizes of up to ∼200 nm were observed. [16][17][18]48 Larger domains in MOCVD processes were only obtained when adding metal halides to the system. 16,31 Such unwanted carbon deposition have many detrimental effects, like serving as nucleation centers, thus increasing the nucleation density (and reducing the domain size), and general contamination of the growth substrate, surface, and edges of the domains.…”

Wafer‐Scale Graphene Anodes Replace Indium Tin Oxide in Organic Light‐Emitting Diodes

“…Additionally, while MOCVD stands for metalorganic chemical vapor deposition due to its original objective for manufacturing III-V compound semiconductors (e.g., GaN) with metalorganic precursors such as AlMe 3 (TMAl) and GaMe 3 (TMGa), it is not mandatory to incorporate organometallic precursors in the MOCVD reactors for the fabrication of other materials. [52] ITO Substrate Cleaning Process: The ITO substrates (ITOGLASS 15P) were purchased from Visiontek Systems Ltd. and were cleaned to remove any grease and impurities prior to device fabrication. The substrates were first cleaned with detergent and rinsed with distilled water to remove some surface grease and particles due to commercial packaging.…”

Progresses in Synthesis and Application of SiC Films: From CVD to ALD and from MEMS to NEMS

“…Under such conditions, the rates of surface chemical reactions are much faster than that of mass transport, i.e., the CVD occurs in limited mass transport-based process [65]. The reviews of Thompson et al [63], Fischer et al [66], Juergensen et al [67], Creighton and Parmeter [68], and Lee et al [69] discuss well the main reactors and growth modes of MOCVD technique. Some MOCVD SiC processes use single-source precursors, such as DEMS [64,70,71].…”