RESEARCH ARTICLE

Batch growth of wafer-scale nanocrystalline NbSe₂ film for surface-enhanced Raman spectroscopy

¹ Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), Singapore 627833, Singapore
² National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China
³ State Key Laboratory of Nuclear Physics and Technology, Center for Applied Physics and Technology, Peking University, Beijing 100871, China
⁴ Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry, Beihang University, Beijing 100191, China
⁵ State Key Laboratory of Flexible Electronics (LoFE), Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), School of Materials Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China
⁶ Guangdong Provincial Key Laboratory of Nano-Micro Materials Research, School of Advanced Materials, Peking University Shenzhen Graduate School, Peking University, Shenzhen 518055, China

^* Corresponding authors (emails: linhh@isce2.a-star.edu.sg (Huihui Lin); iamlywu@njupt.edu.cn (Luyan Wu); chenzhaolong@pku.edu.cn (Zhaolong Chen); chmlij@buaa.edu.cn (Jing Li))

Received: 19 August 2024
Revised: 16 December 2024
Accepted: 31 December 2024

Abstract

Noble metal-based surface-enhanced Raman spectroscopy (SERS) has emerged as an ultrasensitive technique capable of detecting single molecules through their unique vibrational signatures. However, achieving robust SERS nanomaterials that combine significant enhancement factors, scalable reproducibility, and superior chemical stability remains a significant challenge. We present an oxygen-free vapor deposition technique for wafer-scale fabrication of nanocrystalline NbSe₂ (NC-NbSe₂) films on SiO₂/Si substrates, which is compatible with batch production. The NC-NbSe₂ films exhibit remarkable chemical stability across both crystalline domains (average size ~8.1 nm) and grain boundaries. This stability, combined with enhanced surface adsorption and a high density of states near the Fermi level, enables superior SERS performance. Rhodamine 6G detection demonstrates a sensitivity of 1×10⁻¹⁰ M, comparable to noble metal-based SERS substrates. Additionally, the NC-NbSe₂ film maintains stable SERS signals under harsh thermal and chemical conditions. This scalable approach enables the creation of uniform, reproducible SERS atomic thin film, advancing applications in microelectronics and sensing technologies.