Thermal conductivity of suspended MBE-grown PtSe ₂

Abstract Layered platinum diselenide (PtSe₂) grown by molecular beam epitaxy provides a reliable and reproducible alternative to mechanical exfoliation, making it suitable for scalable device integration. In this work, we thoroughly investigate the in-plane thermal conductivity of multilayer suspended PtSe ₂ membranes. For this study, we first achieved the transfer of large-scale epitaxially grown PtSe ₂ and demonstrate a highly efficient process that enables the fabrication of multiple suspended membranes in a single transfer while maintaining the structural quality of the material. Optothermal Raman Technique is then used to investigate the in-plane thermal conductivity of the suspended PtSe₂ membranes. This approach leverages millimeter-scale transfer to conduct systematic ORT measurements, enabling statistical refined thermal conductivity of 11.92 ± 1.78 W·m ⁻¹ ·K ⁻¹ , with negligible dependence on vacuum/air environments. Finally, our results are supported by numerical simulations using a COMSOL model. This work provides significant insights into the thermal properties of PtSe₂, paving the way for the design of high-performance electronic devices with enhanced thermal management capabilities.