Nano-Raman Spectroscopy Analysis of Nanoprotuberances in MoSe2

TL;DR

This study uses nano-Raman spectroscopy to analyze nanoprotuberances in MoSe2 monolayers, revealing contamination effects and establishing a method for identifying surface impurities through spectral analysis.

Contribution

It introduces a novel nano-Raman based approach to detect and analyze nanoprotuberances and surface contamination in 2D MoSe2 materials.

Findings

Identification of spectral peaks linked to nanoprotuberances

Correlation between surface impurities and hyperspectral variations

A new figure of merit for impurity detection

Abstract

Contaminations in the formation of two-dimensional heterostructures can hinder or generate desired properties. Recent advancements have highlighted the potential of tip-enhanced Raman spectroscopy (TERS) for studying materials in the 2D semiconductor class. In this work, we investigate the influence of 50-200nm sized nanoprotuberances within a monolayer of MoSe$_2$ deposited on hBN using nano-Raman spectroscopy, establishing correlations between the presence of localized contaminations and the observed hyperspectral variations. A figure of merit is established for the identification of surface impurities, based on MoSe$_2$ peaks ratio. Notably, new spectral peaks were identified, which are associated with the presence of nanoprotuberances and may indicate contamination and oxidation.