This review investigates the measurement methods employed to assess the geometry and electrical properties of through-silicon vias (TSVs) and examines the reliability issues associated with TSVs in 3D integrated circuits (ICs). Presently, measurements of TSVs primarily focus on their geometry, filling defects, and the integrity of the insulating dielectric liner. Non-destructive measurement techniques for TSV contours and copper fillings have emerged as a significant area of research. This review discusses the non-destructive measurement of contours using high-frequency signal analysis methods, which aid in determining the stress distribution and reliability risks of TSVs. Additionally, a non-destructive thermal detection method is presented for identifying copper fillings in TSVs. This method exploits the distinct external characteristics exhibited by intact and defective TSVs under thermoelectric coupling excitation. The reliability risks associated with TSVs in service primarily arise from copper contamination, thermal fields in 3D-ICs, stress fields, noise coupling between TSVs, and the interactions among multiple physical fields. These reliability risks impose stringent requirements on the design of 3D-ICs featuring TSVs. It is necessary to electrically characterize the influence of copper contamination resulting from the TSV filling process on the reliability of 3D-ICs over time. Furthermore, the assessment of stress distribution in TSVs necessitates a combination of micro-Raman spectroscopy and finite element simulations. To mitigate cross-coupling effects between TSVs, the insertion of a shield between them is proposed. For efficient optimization of shield placement at the chip level, the geometric model of TSV cross-coupling requires continuous refinement for finite element calculations. Numerical simulations based on finite element methods, artificial intelligence, and machine learning have been applied in this field. Nonetheless, comprehensive design tools and methods in this domain are still lacking. Moreover, the increasing integration of 3D-ICs poses challenges to the manufacturing process of TSVs.
Nickel base superalloys are widely used to manufacture turbine blades, and overheating poses a serious threat to the safe service of turbine blades. In this study, a second-generation nickel base single crystal superalloy was taken as the research object, and we carried out the overheating treatment at 1100 °C and 1300 °C, and then tested the creep properties at 1000 °C/300 MPa and 1100 °C/130 MPa. Through systematic analysis of creep properties, γ/γ’ phases, and creep voids, the effects of overheating on the microstructures and creep properties of the experimental superalloy were revealed. The results demonstrate that the effect of overheating at 1100 °C on the microstructure of the experimental superalloy can be ignored, and the effect on the creep property is limited. The degree of γ’ dissolution is gradually increased and the creep property is reduced with overheating time extending at the overheating temperature of 1300 °C.
In deep space exploration the exploration equipment will inevitably experience the harsh environment of cryogenic temperature. Solder joints belong to the most vulnerable parts of electronic equipment, and the harsh environment of extreme cryogenic temperature will seriously threaten the reliability of solder joints. In this paper, Sn3.0Ag0.5Cu/Cu solder joints were prepared and stored at cryogenic temperatures (−50 °C, −100 °C, and −196 °C) for up to 960 h, whilst studying the microstructural evolution and deterioration of shear properties. The results showed that the influence of cryogenic temperature on microstructure deterioration was greater than that of storage time. With the decrease of storage temperature and the extension of storage time, the Ag3Sn intermetallic compounds (IMCs) were uniformly dispersed in the β-Sn matrix; the size decreased and the number increased. After being stored at −196 °C for 960 h, some microcracks appeared at the interface of the solder joints. Meanwhile, the shear force of the solder joints was reduced by 19.02%, and the fracture mode changed from ductile fracture to ductile–brittle mixed fracture. Therefore, it is of great scientific significance to reveal the microstructural evolution and deterioration of shear properties of the solder joints under long-term storage at cryogenic temperatures.
Driven by the rapid development of deep-space exploration, artificial intelligence, and new energy vehicles, the integration density of power devices has been significantly improved, creating an urgent demand for electronic packaging interconnection materials with low thermal resistance, high reliability, and thermomechanical stress resistance. Porous metals have become a major research focus for packaging interconnection materials owing to their high specific surface area; controllable porous structure; and excellent thermal, electrical, and mechanical properties. Among various porous metals, porous metal has attracted extensive attention in the field of electronic packaging interconnection due to its low cost, high thermal conductivity, superior wettability, and good processability. This paper systematically reviews the research progress of porous copper (Cu)-based interconnection materials in electronic packaging, covering the preparation methods, interconnection methods and reliability of porous Cu-based interconnection materials. In addition, the existing challenges in the preparation, interconnection processes, and reliability evaluation are summarized, which provides clear research directions for the structural optimization and engineering application of such materials in the future.