Download or read book Understanding Heat Transport at Interfaces for Thermal Management of Electronics written by Lenan Zhang and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery and development of two-dimensional (2D) materials offer new opportunities for high-performance nanoscale electronics. However, new material systems involve new device architectures, which leads to new challenges on both the electronic and thermal design. While significant progress has been made to understand and engineer the electrical properties of 2D devices, the thermal problems remain relatively poorly understood. Since many 2D electronics can reach very high-power density (>104 W/cm2 ), the dense vertical integration of multilayers within a few nanometers leads to a significant temperature rise (>150 °C), which becomes the bottleneck of device performance. These thermal challenges are associated with two critical thermophysical properties of 2D materials, i.e., the thermal expansion and the interfacial thermal transport. In addition, to address the thermal management of 2D electronics, novel cooling approaches with insights gained from 2D thermal interfaces are in high demands. This thesis performed a systematic study on the thermal expansion and thermal transport of the van der Waals (vdW) bonded 2D interfaces, and developed highly efficient thermal management solutions based on two-phase cooling. First, we developed for the first time a pure experimental approach to accurately measure the thermal expansion coefficients(TECs) of various 2D materials. Our measurements confirmed the correct physical range of 2D monolayer TECs and hence addressed the more than two orders of magnitude discrepancies in literature. Second, we investigated the thermal transport across various 2D interfaces. In particular, we elucidated the role of vdW interaction in the anisotropic thermal transport of substrate-supported 2D monolayers and identified an optimal vdW interaction toward the maximum total heat transfer. On the other hand, we explored the twist-angle dependence of 2D interfacial thermal transport. We observed that depending on different material systems, the thermal transport of 2D materials can exhibit both strong and weak twist-angle dependences, which creates a new degree of freedom to manipulate heat at the atomic level. Lastly, with fundamental understanding of 2D thermal interfaces, we designed and optimized a liquid-vapor thin film evaporator based on microstructured surfaces, enabling high-performance thermal management of 2D electronics. This thesis provides a holistic understanding for the fundamental thermal properties of 2D materials and interfaces, which are critical to address the thermal crisis of 2D electronics. We believe the simulation, experimental, and design approaches developed in this thesis can serve as a guideline for the next-generation 2D electronics with unprecedented reliability and performance.