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As the trend towards the densification of integrated circuit (IC) devices continues, the complexity of interfaces involving dissimilar materials and thermo-mechanical interactions has increased. Highly integrated systems in packages now comprise numerous thin layers made from various materials. The interfaces between these different materials represent a vulnerable point in ICs due to imperfect adhesion and stress concentrations caused by mismatches in thermo-mechanical properties such as Young's modulus, coefficients of thermal expansion (CTE), and hygro-swelling-induced expansion. This study investigates the impact of thermal variations on the fracture behavior of three bi-material interfaces used in semiconductor packaging: epoxy molding compound–silicon (EMC–Si), silicon oxide–polyimide (SiO2–PI), and PI–EMC. Using double cantilever beam (DCB) tests, we analyzed these interfaces under mode I loading at three temperatures: −20 °C, 23 °C, and 100 °C, under both quasi-static and cyclic loading conditions. This provided a comprehensive analysis of the thermal effects across all temperature ranges in microelectronics. The results show that temperature significantly alters the failure mechanism. For SiO2–PI, the weakest point shifts from silicon at low temperatures to the interface at higher temperatures due to thermal stress redistribution. Additionally, the fracture energy of the EMC–Si interface was found to be highly temperature-dependent, with values ranging from 0.136 N/mm at low temperatures to 0.38 N/mm at high temperatures. SiO2–PI's fracture energy at high temperature was 42% less than that of EMC–Si. The PI–EMC interface exhibited nearly double the crack growth rate compared to EMC–Si. The findings of this study provide valuable insights into the fracture behavior of bi-material interfaces, offering practical applications for improving the reliability and design of semiconductor devices, especially in chip packaging. [ABSTRACT FROM AUTHOR]

Chip packaging engineering has evolved significantly to meet the performance demands of integrated circuits (IC) and micro-electromechanical systems (MEMS). Layers, mainly composed of metals, ceramics, and polymers are utilized to safeguard circuits and facilitate electrical connections. While, mechanical testing ensures bonding properties and reliability of bi-material interfaces in these components, there is a lack of discussion on the advantages and disadvantages of different test methods. Environmental factors, notably humidity and temperature, pose significant challenges, with a gap in understanding each condition's impact on interfaces. This review aims to provide comprehensive insights into the mechanical characterization of bi-material interfaces and their response to environmental conditions. It's divided into two main parts: a review of mechanical approaches in characterizing bi-material interfaces, including strength and quasi-static fracture tests and the presentation of test results considering temperature and humidity influence. The paper highlights the effects of humidity and high temperatures on the interface fracture energy, primarily due to the properties of polymeric materials in packaging for different interfaces. Additionally, it offers a summarized approach for selecting testing setups based on the desired interface. [ABSTRACT FROM AUTHOR]