Nova metodologia para obtenção do módulo de Young por técnicas de microscopia de varredura por sonda

Abstract

Young’s modulus plays a key role in determining the compatibility of materials for various applications, including two-dimensional (2D) materials such as graphene and transition metal dichalcogenides (TMDs). Due to substrate effects, traditional indentation methods can face challenges when dealing with ultrathin 2D materials. To overcome this limitation, this work proposes using polydimethylsiloxane (PDMS) as a compatible substrate for force curves in atomic force microscopy (AFM). Based on an analytical model established by Timoshenko and Woinowsky-Krieger, this method enables accurate estimates of Young’s modulus by measuring flake thickness, applied force, and deformation. The results obtained by our approach show strong agreement with the existing literature for several 2D materials. Furthermore, PDMS, widely used in exfoliation and mechanical transfer by viscoelastic stamping, has an easily measurable Young’s modulus, allowing more efficient Young’s modulus determinations. With the expansion of the study of ultrathin materials, this new methodology, proposing PDMS as a substrate for nanoindentation measurements by AFM techniques, improves the accessibility and efficiency in measuring Young’s modulus, which significantly contributes to the advancement of the applications of these innovative 2D materials.