Extracting deeply buried thermal resistance in Au/Au-bonded thick Si-on-diamond
Abstract
Efficient thermal management is essential for high-performance computing and AI chips to prevent overheating and ensure reliable operation. Metallic interlayers, known for their high thermal conductivity and thermomechanical compatibility, facilitate the integration of chips with highly conductive heat spreaders, thereby improving heat dissipation. Accurate characterization of the interfacial thermal resistance (ITR) in such thick chip/heat-spreader substrates is therefore critical for optimizing bonding processes. In this study, we fabricated a heterostructure by bonding a thick Si to a diamond heat spreader via an Au/Au interlayer and extracted the ITR at the buried Au/Au interface. Significantly, we introduce a deeply buried thermal resistance extraction method that harnesses the inherent Au interlayer of Au/Au bonding and a sequential delamination technique to accurately measure the temperature-dependent thermal conductivity and ITR of each interlayer. The proposed method enables accurate quantification of ITR for individual metallic and interfacial layers within Au/Au-bonded heterojunctions—even in thicker device layers and high-thermal-conductivity heat sinks. By resolving layer-specific thermal properties and ITR, this approach facilitates rational optimization of wafer-level metal-bonding processes, unlocking the full thermal management potential of ultrahigh-conductivity substrates like diamond for high-power-density devices.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (13)
Yang He
Yinfei Xie
School of Science and Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System, Harbin Institute of Technology 1 , Shenzhen 518055,
Jiwen Zhao
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology 2 , Harbin 150080,
Kechen Zhao
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology 2 , Harbin 150080,
Xiaowu Gao
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology 2 , Harbin 150080,
Huiyu Xu
Weiye Liu
School of Science and Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System, Harbin Institute of Technology 1 , Shenzhen 518055,
Bing Dai
Yan Zhou
Lifa Zhang
Ministry of Education Key Laboratory of NSLSCS, Phonon Engineering Research Center of Jiangsu Province, Center for Quantum Transport and Thermal Energy Science, Institute of Physics Frontiers and Interdisciplinary Sciences, School of Physics and Technology, Nanjing Normal University , Nanjing 210023,
Jiaqi Zhu
Department of Chemistry
Huaixin Guo
National Key Laboratory of Solid-State Microwave Devices and Circuits 2 , Nanjing 210016,
Huarui Sun
School of Science and Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System, Harbin Institute of Technology Shenzhen 1 , Shenzhen 518055,