In Case You Missed It
Microwave Communication
“A Room-Temperature Cavity-Magnonic Source of Correlated Microwave Magnon Polariton Pairs”
Authors: Qiuyuan Wang, Aravind Karthigeyan, Chung-Tao Chou and Luqiao Li
Abstract: Correlated microwave photon sources are required for the development of quantum-limited sensing, signal amplification and communication. The devices typically have a millikelvin operating temperature, which limits their broader application. Here, the authors report a hybrid magnon–photon platform that is based on a printed-circuit-board microstrip resonator coupled to a yttrium iron garnet film and emits strongly correlated microwave signals at room temperature. The authors’ approach achieves non-degenerate excitations by coupling magnon modes simultaneously with two cavity photon modes. Through the magnon–photon interactions in the corresponding linear and nonlinear regimes, one input microwave photon splits into a pair of magnon polaritons that have distinct frequencies and maintain strong intermode correlations. The nonlinear magnon polariton dynamics exhibit true randomness and robust multichannel correlations, and the authors use the system to demonstrate microwave communication with reliable signal transmission through two noisy channels. (Nature Electronics, Aug. 19, 2026, https://www.nature.com/articles/s41928-026-01689-y)
PCB Recycling
“Kinetically Inert Covalent Adaptable Networks Enable Holistic Resource Recovery from High-Performance Printed Circuit Boards”
Authors: H. Hu, T. Song, X. Chen, et al.
Abstract: The massive accumulation of electronic waste (e-waste) globally demands sustainable strategies for printed circuit boards (PCBs), a goal currently hindered by the pervasive use of irreversibly cured epoxy resins. Here, a kinetically inert covalent adaptable network (CAN) is designed for recyclable high-performance PCB based on gem-dimethyl dithioketal (gTK) epoxy resins. The gem-dimethyl effect significantly enhances the stability of gTK bonds through steric hindrance, kinetically blocking undesirable acidolysis and heat-induced exchange reactions. The fabricated gTKPCB satisfies the demanding commercial specifications, exhibiting robust thermomechanical stability (~ 220°C), chemical resistance, and highly reliable electrical interconnection under long-term thermal conditions (105°C, 90 d). Crucially, gTKPCBs undergo oxidation-specific degradation in H2O2 solution, enabling the direct, nondestructive recovery of high-purity copper (99.5%) and glass fibers, and the degraded resins as adhesives. Life cycle assessment confirms that this valorization approach significantly mitigates environmental impact compared to traditional metallurgical recovery processes. This work provides a powerful blueprint for sustainable transitions in the electronics industry and offers a holistic solution for e-waste recycling. (Nature Communications, Aug. 27, 2026, https://www.nature.com/articles/s41467-026-77223-7)
Surface Finishes
“Interfacial Reactions of Sn-19Bi-19In Solder on OSP and ENIG Surface Finishes During Thermal Aging”
Authors: Ju-Hyeon Kim, et al.
Abstract: This study investigates the interfacial reactions and mechanical properties of Sn-19Bi-19In (SBI) solder on OSP and ENIG finishes under isothermal aging at 85 °C for up to 500 h. The microstructure analysis of the SBI solders on the two surface finishes (OSP and ENIG) reveals that the intermetallic compound (IMC) morphologies of these SBI/OSP and SBI/ENIG joints are fundamentally distinct from those of conventional SAC solder joints. Our findings indicate that the high In concentration of SBI solder induces the formation of In-containing ternary IMCs [Cu6(Sn,In)5 for OSP and Ni(In0.3Sn0.7)2 for ENIG], which strongly contribute to the IMC morphologies. For the SBI/OSP joints, Cu6(Sn,In)5 IMCs form a rod-type structure, deviating from the typical scallop-type growth of SAC/OSP joints. Similarly, for the SBI/ENIG joints, Ni(In0.3Sn0.7)2 IMCs develop a stacked cuboid morphology, which is also different from that of conventional SAC/ENIG joints. The IMC thickness of the SBI joints on both finishes follows the parabolic relationship, indicating that the IMC growth proceeds through a diffusion-controlled reaction. The ball shear tests reveal that the SBI/OSP joints undergo a ductile-to-brittle transition of the fracture mode with aging, whereas the SBI/ENIG joints exhibit brittle fracture for all aging conditions and their maximum shear strength decreases after prolonged aging. The fracture analysis of the sheared SBI/ENIG joints reveals that this strength decrease appears closely related to the shift of the fracture location toward the IMC/Ni3P interface. These findings provide a basis for understanding the interfacial reliability of Sn-Bi-In solder joints on different surface finishes. (Journal of Electronic Materials, vol. 37, no. 1905, Aug. 27, 2026, https://link.springer.com/article/10.1007/s10854-026-18298-2)
Thermal Management
“Spatiotemporal Mapping of Anisotropic Thermal Transport in Gan Thin Films Via Ultrafast X-ray Diffraction”
Authors: Thanh Nguyen, et al.
Abstract: Efficient thermal management is essential for the reliability of modern power electronics, where increasing device density leads to severe heat dissipation challenges. In thin-film systems, however, thermal transport is often compromised by interfacial resistance and microscale defects introduced during synthesis or transfer, which are difficult to characterize using conventional techniques. Here the authors present a noncontact, spatiotemporal-resolved ultrafast x-ray diffraction method to extract in-plane thermal conductivity and thermal boundary conductance, using GaN thin films on silicon as a model system. By tracking the pump-induced lattice strain, they reconstruct the lateral heat flow dynamics and quantitatively probe thermal transport near a wrinkle defect. This study uncovers pronounced asymmetric heat dissipation across the wrinkle, with a four-fold reduction in the local thermal conductivity near the wrinkle and a 25% drop in interfacial conductance. The work demonstrates that ultrafast x-ray diffraction can serve as a precise thermal metrology tool for characterizing heat transport in multilayered thin-film structures for next-generation microelectronic devices. (Nature Communications, Jul. 29, 2026, https://www.nature.com/articles/s41467-026-75414-w)