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ABSTRACT The quest for faster and more densely packed microelectronic circuits has necessitated significant advancements in thermal management and encapsulant manufacturing technologies. This pursuit has driven the development of innovative methods to enhance heat flux and thermal transfer in microelectronics packaging. A critical issue is the thermal stress induced by the coefficient of thermal expansion (CTE) mismatch between the chip and the substrate, threatening the chip's mechanical integrity and lifespan. To address this challenge, there is a growing emphasis on using underfills to improve thermal transfer and heat dissipation. The current study focuses on using hexagonal boron nitride (h‐BN) nanofillers for robust thermal support in microelectronics packaging. This study deploys epoxy adhesives to integrate nanofillers, where precise dispersion is crucial for optimizing thermal and mechanical properties. Findings show 1500‐ and 500‐nm h‐BN enhance axial thermal conductivity and diffusivity linearly with filler content, while the 70‐nm h‐BN plateaus at 3% volume. The 70‐nm h‐BN demonstrates superior radial thermal performance. 

ABSTRACT The synthesis of two‐dimensional transition metal dichalcogenide (2D‐TMD) materials gives rise to inherent defects, specifically chalcogen vacancies, due to thermodynamic equilibrium. Techniques such as chemical vapor deposition (CVD), metal‐organic chemical vapor deposition (MOCVD), atomic layer deposition (ALD), flux growth method, and mechanical exfoliation produce large‐scale, uniform 2D TMD films, either in bulk or monolayers. However, defects on the film surface impact its quality, and it is necessary to measure defect density. The phonon confinement model indicates that the first‐order Raman band frequency shift depends on defect density. Monolayer Molybdenum disulfide (MoS₂) exhibits three phonon dispersions at the Brillouin zone edge (M point): out‐of‐plane optical phonon vibration (ZO), in‐plane longitudinal optical phonon vibration (LO), and in‐plane transverse optical phonon vibration (TO). The LO and ZO modes overlap with Raman in‐plane vibration (𝐸¹_2g) and Raman out‐of‐plane vibration (𝐴_1g), respectively, causing peak broadening. In the presence of defects, the Raman 𝐸¹_2gvibration energy decreases due to a reduced restoring force constant. The Raman 𝐴_1gvibration trend is random, influenced by both restoring force constant and mass. The study introduces a quantitative defect measurement technique for CVD‐grown monolayer MoS₂using Raman 𝐸¹_2gmode, employing sequential data processing algorithms to reveal defect density on the film surface.