Materials and Equipment Technology Supporting Electronics Packaging

The exponential increase in server power density and heat generation within data centers due to the processing and storage of massive data volumes has led to a significant focus on efficient cooling technologies. Conventional air-cooled data centers allocate a substantial portion of energy towards cooling information technology equipment (ITE), necessitating alternative cooling solutions. Single-phase liquid immersion cooling (SP-LIC) has emerged as a promising approach, offering enhanced thermal mass and efficient heat dissipation, particularly suitable for hyper-scale, edge, and modular data center applications. This study investigates the impact of single-phase liquid immersion cooling fluids on the thermomechanical properties of the TG-400 substrate core, a vital component in electronic packaging. Our previous study focused on a different substrate core material, I-Speed, and now extends the analysis to TG-400. The key properties under scrutiny include the Elastic Modulus (E) and Glass Transition Temperature (Tg), critical for mechanical design and reliability assessment of electronic packages. The research involves subjecting the TG-400 substrate core to thermal aging in various immersion cooling fluids, including synthetic hydrocarbon fluid (EC100) and Polyalphaolefin 6 (PAO 6), alongside exposure to ambient air. Aging occurs at two distinct temperatures, 85°C and 125°C, for 720 hours each. The study evaluates changes in complex modulus pre- and post-aging, providing insights into the material’s behavior under different thermal conditions and immersion cooling environments. Furthermore, this research contributes to understanding the reliability and failure mechanisms associated with immersion cooling technologies, essential for advancing efficient and sustainable data center cooling strategies. By examining both the Elastic Modulus and Glass Transition Temperature of the TG-400 substrate core, this study enhances our knowledge of material compatibility and performance in immersive cooling settings, aiding in the development of robust electronic packaging designs for modern data center infrastructures.

Preparing Biomeds For the Future

The data center's server power density and heat generation have increased exponentially because of the recent, unparalleled rise in the processing and storing of massive amounts of data on a regular basis. One-third of the overall energy used in conventional air-cooled data centers is directed toward cooling information technology equipment (ITE). The traditional air-cooled data centers must have low air supply temperatures and high air flow rates to support high-performance servers, rendering air cooling inefficient and compelling data center operators to use alternative cooling technology. Due to the direct interaction of dielectric fluids with all the components in the server, single-phase liquid immersion cooling addresses mentioned problems by offering a significantly greater thermal mass and a high percentage of heat dissipation. Single-phase liquid immersion cooling is a viable option for hyperscale, edge, and modular data center applications because, unlike direct-to-chip liquid cooling, it does not call for a complex liquid distribution system configuration and the dielectric liquid can make direct contact with all server components. Immersion cooling is superior to conventional air-cooling technology in terms of thermal energy management; however, there have been very few studies on the reliability of such cooling technology. A detailed assessment of the material compatibility of different electronic packaging materials for immersion cooling was required to comprehend their failure modes and reliability. For the mechanical design of electronics, the modulus and glass transition temperature (Tg) are essential material characteristics. The substrate is a crucial element of an electronic package that has a significant impact on the reliability and failure mechanisms of electronics at both the package and the board level. As per Open Compute Project (OCP) design guidelines for immersion-cooled IT equipment, the traditional material compatibility tests from standards like ASTM 3455 can be used with certain appropriate adjustments. The primary focus of this research is to address two challenges: The first part is to understand the impact of thermal aging on the thermomechanical properties of the halogen-free substrate core in the single-phase immersion cooling. Another goal of the study is to comprehend how thermal aging affects the thermomechanical characteristics of the substrate core in the air. In this research, the substrate core is aged in synthetic hydrocarbon fluid (EC110), polyalphaolefin 6 (PAO 6), and ambient air for 720 h each at two different temperatures: 85 °C and 125 °C, and the complex modulus and the glass transition temperature before and after aging are calculated and compared.

The data center’s server power density and heat generation have increased exponentially because of the recent, unparalleled rise in the processing and storing of massive amounts of data on a regular basis. One-third of the overall energy used in conventional air-cooled data centers is directed toward cooling information technology equipment (ITE). The traditional air-cooled data centers must have low air supply temperatures and high air flow rates to support high-performance servers, rendering air cooling inefficient and compelling data center operators to use alternative cooling technology. Due to the direct interaction of dielectric fluids with all the components in the server, single-phase liquid immersion cooling (Sp-LIC) addresses mentioned problems by offering a significantly greater thermal mass and a high percentage of heat dissipation. Sp-LIC is a viable option for hyper-scale, edge, and modular data center applications because, unlike direct-to-chip liquid cooling, it does not call for a complex liquid distribution system configuration and the dielectric liquid can make direct contact with all server components. Immersion cooling is superior to conventional air-cooling technology in terms of thermal energy management however, there have been very few studies on the reliability of such cooling technology. A detailed assessment of the material compatibility of different electronic packaging materials for immersion cooling was required to comprehend their failure modes and reliability. For the mechanical design of electronics, the modulus, and thermal expansion are essential material characteristics. The substrate is a crucial element of an electronic package that has a significant impact on the reliability and failure mechanisms of electronics at both the package and the board level. As per Open Compute Project (OCP) design guidelines for immersion-cooled IT equipment, the traditional material compatibility tests from standards like ASTM 3455 can be used with certain appropriate adjustments. The primary focus of this research is to address two challenges: The first part is to understand the impact of thermal aging on the thermo-mechanical properties of the halogen-free substrate core in the single-phase immersion cooling. Another goal of the study is to comprehend how thermal aging affects the thermo-mechanical characteristics of the substrate core in the air. In this research the substrate core is aged in synthetic hydrocarbon fluid (EC100), Polyalphaolefin 6 (PAO 6), and ambient air for 720 hours each at two different temperatures: 85°C and 125°C and the complex modulus before and after aging are calculated and compared.

Demands for increased interconnection density and higher bandwidth, coupled with stringent cost constraints of advanced wide bandwidth telecommunication switching equipment, are exhausting conventional electrical interconnection capabilities. The requirement for greater interconnection capabilities, spawned in part by the advances in integrated circuit technologies and the need for enhanced digital services, dictate that technology advancement must occur in traditional electronic packaging and/or interconnection techniques. The resolution of these technological needs is paramount for the successful competitive introduction of these systems. Presently, a "bottle-neck" occurs at the board-to-board level of the interconnection hierarchy. Therefore, an opportunity exists for the development of new optical interconnection techniques which can be incorporated into system designs beginning at this interconnection level and beyond. The strategic insertion of optical interconnection technology into these electronic processing systems not only meets projected performance requirements, but potentially offers them at a competitive cost. This paper describes some of the new optical strategies switching equipment designers are incorporating into today's products. These strategies range from optical data links to an implementation of a flexible optical backplane called OptiFlex.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The problem of heat inside data centers is becoming more serious nowadays due to increasing computing and storage demand. As the power density keeps going up, it is getting much harder to keep the electronics cool with only traditional air cooling. Cooling Information Technology Equipment (ITE) by air requires a lot of energy. Researchers are exploring better cooling methods that save energy while keeping systems reliable. One method that is getting noticed now is called Single-Phase Liquid Immersion Cooling (SP-LIC). SP-LIC submerges electronics in dielectric fluids that don’t conduct electricity. This liquid can move heat away from the parts much faster and more effectively than air cooling can do. SP-LIC suits edge, modular, and hyperscale data centers where energy and space matter. As more companies start thinking about using immersion cooling, it is important to know how these liquids will affect the materials inside electronic devices. In this work, the focus is on the ASTRA M77 substrate core, which is a very important material for electronic packaging. This paper is also building on some previous research on another substrate, called I-Speed — a low-loss, high-speed PCB core laminate used in high-speed digital circuits, and here, the main goal is to study how ASTRA M77 will behave after staying in cooling liquid for a long time. The Glass Transition Temperature (Tg) and Elastic Modulus (E) are key indicators of long-term stability. This study examined the ASTRA M77 samples subjected to two immersion cooling fluids, EC110 (a synthetic oil) and PAO6 (a polyalphaolefin), to analyze their behavior after 720 hours of exposure at 85°C. Results show that while the elastic modulus decreased after immersion—indicating the material becomes slightly more flexible—the Tg remained stable. This suggests that ASTRA M77 maintains its thermal reliability even after prolonged fluid exposure, making it a promising candidate for immersion-cooled systems. The reason for aging these materials was to replicate the conditions they would experience during actual operation in a real data center environment. Measurement of complex modulus before and after the aging process can provide insight into their long-term behavior. These tests help answer key questions about ASTRA M77’s behavior under immersion. Learning how these cooling liquids affect substrate materials can help design better and more efficient thermal systems for electronics. Also, it gives useful knowledge for companies and engineers who want to make their cooling systems both sustainable and reliable in the future.