Direct Measurements of Anisotropic Thermal Transport in γ-InSe Nanolayers via Cross-Sectional Scanning Thermal Microscopy

Gonzalez-Munoz, Sergio; Agarwal, Khushboo; Castanon, Eli G.; Kudrynskyi, Zakhar R.; Kovalyuk, Zakhar D.; Spièce, Jean; Kazakova, Olga; Patanè, Amalia; Kolosov, Oleg V.

Abstract

Van der Waals (vdW) atomically thin materials and their heterostructures offer a versatile platform for the management of nanoscale heat transport and the design of novel thermoelectrics. These require the measurement of highly anisotropic heat transport in vdW‐based nanolayers, a major challenge for nanostructured materials and devices. In the present study, a novel effective method of cross‐sectional scanning thermal microscopy was used to map and quantify the anisotropic heat transport in nanoscale thick layers of vdW materials and the material‐substrate interfaces. This technique measures the heat conducted into a vdW crystal via the nanoscale apex of a heat‐sensitive probe. The crystal is nano‐polished via Ar ion beams generating an oblique nearly atomically flat surface. By measuring the thermal conductance variation as a function of increasing layer thickness, the transition between the cross‐plane and in‐plane heat transport (defined by heat conductivity anisotropy) is acquired. By using an analytical model validated by finite element simulations, anisotropic thermal transport in a gamma indium selenide crystal nano‐thin flake on a Si substrate was studied, obtaining results corresponding to anomalously low anisotropic thermal conductivities of kxy = 2.16 Wm−1 K−1 in‐plane and kz = 0.89 Wm−1 K−1 cross‐plane confirming its potential for thermoelectric applications.

Citation

Gonzalez-Munoz, S., Agarwal, K., Castanon, E. G., Kudrynskyi, Z. R., Kovalyuk, Z. D., Spièce, J., …Kolosov, O. V. (2023). Direct Measurements of Anisotropic Thermal Transport in γ-InSe Nanolayers via Cross-Sectional Scanning Thermal Microscopy. Advanced Materials Interfaces, 10(17), Article 2300081. https://doi.org/10.1002/admi.202300081

• Journal Article Type: Article
• Acceptance Date: Mar 23, 2023
• Online Publication Date: May 11, 2023
• Publication Date: Jun 16, 2023
• Deposit Date: May 15, 2023
• Publicly Available Date: May 15, 2023
• Journal: Advanced Materials Interfaces
• Electronic ISSN: 2196-7350
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 17
• Article Number: 2300081
• DOI: https://doi.org/10.1002/admi.202300081
• Keywords: Cross‐sectional scanning thermal microscopy, gamma indium selenide, nanoscale heat transport, thermal conductivity anisotropy, van der Waals materials
• Public URL: https://nottingham-repository.worktribe.com/output/20567497
• Publisher URL: https://onlinelibrary.wiley.com/doi/10.1002/admi.202300081