Two-dimensional (2D) semiconducting monolayers such as transition metal dichalcogenides (TMDs) are promising channel materials to extend Moore's Law in advanced electronics. Synthetic TMD layers from chemical vapor deposition (CVD) are scalable for fabrication but notorious for their high defect densities. Therefore, innovative endeavors on growth reaction to enhance their quality are urgently needed. Here, we report that the hydroxide W species, an extremely pure vapor phase metal precursor form, is very efficient for sulfurization, leading to about one order of magnitude lower defect density compared to those from conventional CVD methods. The field-effect transistor (FET) devices based on the proposed growth reach a peak electron mobility ~200 cm/Vs (~800 cm/Vs) at room temperature (15 K), comparable to those from exfoliated flakes. The FET device with a channel length of 100 nm displays a high on-state current of ~400 µA/µm, encouraging the industrialization of 2D materials.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9293887 | PMC |
http://dx.doi.org/10.1038/s41467-022-31886-0 | DOI Listing |
Small
January 2025
KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
Non-layered 2D materials offer unique and more advantageous physicochemical properties than those of conventional 2D layered materials. However, the isotropic chemical bonding nature of non-layered materials hinders their lateral growth, making the synthesis of large-area continuous thin films challenging. Herein, a facile kinetically tailored chemical vapor deposition (KT-CVD) approach is introduced for the synthesis of 2D molybdenum nitride (MoN), a representative non-layered material.
View Article and Find Full Text PDFMater Horiz
January 2025
Key Laboratory of Advanced Marine Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.
MAX (MAX) phases are a novel class of materials with a closely packed hexagonal structure that bridge the gap between metals and ceramics, garnering tremendous research interest worldwide in recent years. Benefiting from their unique layered structure and mixed covalent-ionic-metallic bonding characteristics, MAX phase coatings possess excellent oxidation resistance, and exceptional electrical and thermal conductivities, making them highly promising for applications in advanced nuclear materials, battery plate protection materials, and aero-engine functional materials. This review aims to provide a comprehensive understanding of MAX phase coatings.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Key Laboratory of Ecological Metallurgy of Multi-Metal Intergrown Ores of Ministry of Education, School of Metallurgy, Northeastern University, Shenyang, 110819, Liaoning, China.
In the process of industrialization, it is found that the calcination process is an important factor affecting the reduction rate, which determines the energy consumption and carbon emission of the reaction process. In this study, the micro-nano physical model of the factors affecting the reduction rate of calcined precursors was constructed by coloring the SEM results of pellets before and after calcination with Gaussian height expression and combining Clausius and Gibbs equations. The influence of the formation degree of the internal pores of the pellets on the reduction rate was analyzed by controlling the calcination time of the precursor.
View Article and Find Full Text PDFTalanta
December 2024
Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, 2800, Denmark.
Detection of airborne chemical threats is an emerging challenge amidst the prevailing tumultuous global milieu. Extensive investigation has showcased the substantial promise of surface-enhanced Raman spectroscopy (SERS) for the on-site identification of hazardous chemicals present in liquid mediums, whether directly from a fluid source or through methodologies such as swab sampling. Nonetheless, exploration into the applicability of SERS for the detection of gas or vapor-phase chemical threats remains severely constrained.
View Article and Find Full Text PDFCommun Eng
January 2025
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, PR China.
Conventional electronic chip packaging generates a huge thermal resistance due to the low thermal conductivity of the packaging materials that separate chip dies and coolant. Here we propose and fabricate a closed high-conducting heat chip package based on passive phase change, using silicon carbide which is physically and structurally compatible with chip die materials. Our "chip on vapor chamber" (CoVC) concept realizes rapid diffusion of hot spots, and eliminates the high energy consumption of refrigeration ordinarily required for heat management.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!