In this article, we are proposing a thorough analysis of the cross, and the in-plane thermal conductivity of thin-film materials based on the 3$ω$ method. The analysis accommodates a 2D mathematical heat transfer model of a semi-infinite body and the details of the sample preparation followed by the measurement process. The presented mathematical model for the system considers a two-dimensional space for its solution. It enables the calculation of the cross-plane thermal conductivity with a single frequency measurement, the derived equation opens new opportunities for frequency-based and penetration-depth dependent thermal conductivity analysis. The derived equation for the in-plane thermal conductivity is dependent on the cross-plane thermal conductivity. Both in and cross-plane thermal conductivities enable the measurements in two steps of measurements, the resistance-temperature slope measurement and another set of measures that extracts the third harmonic of the voltage signal. We evaluated the methodology in two sets of samples, silicon nitride and boron nitride, both on silicon wafers. We observed anisotropic thermal conductivity in the cross and the in-plane direction, despite the isotropic nature of the thin films, which we relate to the total anisotropy of the thin film-substrate system. The technique is conducive to the thermal analysis of next-generation nanoelectronic devices.
Depth-Resolved Thermal Conductivity of HFCVD Diamond Films via Square-Pulsed Thermometry
School of Energy and Power Engineering, Huazhong University of Science and Technology（华中科技大学能源与动力工程学院）；Institute for Advanced Materials and Technology, University of Science and Technology Beijing（北京科技大学先进材料与技术研究院）；Shunde Graduate School, University of Science and Technology Beijing（北京科技大学顺德研究生院）；School of Energy and Power Engineering, Nanjing University of Science and Technology（南京理工大学能源与动力工程学院）
Laser Annealing of Transparent ZnO Thin Films: A Route to Improve Electrical Conductivity and Oxygen Sensing Capabilities
Instituto de Nanociencia y Materiales de Aragón, CSIC-Universidad de Zaragoza（阿拉贡纳米科学与材料研究所，西班牙科学理事会-萨拉戈萨大学）；Univ. Grenoble Alpes, CNRS, Grenoble INP, LMGP（格勒诺布尔阿尔卑斯大学，法国国家科学研究中心，格勒诺布尔理工学院）
