Over the past decade, electronic parts have become smaller, more complex, and highly functional. This is well understood for many products within the consumer and handheld markets. Miniaturization, however, is also impacting sectors such as aerospace and automotive, pushing the limits of already harsh environments. As more power is driven through active devices, the integrity of materials used to provide the electrically conductive interfaces is becoming increasingly critical. For many applications, adhesive films have been the preferred material because they offer a variety of performance and operational advantages such high electrical and thermal conductivity, uniform bondlines, superior adhesion, and low processing temperatures. Today, as miniaturization pushes power-density limits and although devices are also being exposed to high operating temperatures, even for traditionally robust adhesive films, it is challenging to cope with these conditions. In sectors such as aerospace where high reliability is essential, material capability must evolve to deliver on fail-safe performance expectations. This study compares the performance of an established and widely used electrically conductive film adhesive with that of a newly developed film designed to provide improved mechanical performance over a higher elevated temperature range.

Over the past decade, electronic parts have become smaller, more complex and higher functioning. This is well-understood for many products within the consumer and handheld markets. Miniaturization, however, is also impacting sectors such as aerospace and automotive, pushing the limits of already harsh environments. As more power is driven through active devices, the integrity of materials used to provide the electrically conductive interfaces is becoming increasingly critical. For many applications, adhesive films have been the preferred material because they offer a variety of performance and operational advantages such high electrical and thermal conductivity, uniform bondlines, superior adhesion and low processing temperatures. Today, though, as miniaturization pushes power-density limits and devices are also being exposed to high operating temperatures, even traditionally robust adhesive films are challenged to cope with these conditions. In sectors such as aerospace where high reliability is essential, material capability must evolve to deliver on fail-safe performance expectations. This paper will compare the performance of an established and widely used electrically conductive film adhesive with that of a newly developed film designed to provide improved mechanical performance over a higher elevated temperature range.

Assembly adhesives play a critical role in microelectronic packaging and contribute significant value for circuit assembly interconnection, protection, and thermal management. Of particular interest with today’s more powerful systems is thermal management of high-power density electronic systems, including power modules, power amplifiers, communication systems, and directed energy systems. As requirements for performance and functionality increase, heat generated from these devices increases exponentially. For example, local heat flux can easily exceed 50 W/cm2 for IGBT power modules while it may reach several hundred Watts/cm2 at active areas for Gallium Nitride (GaN) power amplifiers. Simultaneously, many of these systems demand a higher level of electrical insulation to eliminate or minimize current leakage to ensure high reliability over a long service life. Effectively and safely dissipating the high heat and ensuring excellent electrical insulation has become an increasingly critical and challenging task in the microelectronics packaging technology for aerospace and defense systems. This paper presents integration of thermally conductive adhesives with an electrically insulative polyimide film into a carefully engineered laminate, which enables high thermal transfer and robust electrical insulation. This new film adhesive provides outstanding compliance and augmented tolerance to large topographical features and warpage (5-7 mils). This film adhesive is one of the potential solutions to addresses the evolving needs of the electronics assembly industry in the areas of management of high-power systems

Integration of smaller, higher-functioning devices and use of advanced high thermal chip structures present thermal management challenges in the aerospace sector where reliability is the top priority and fail-safe processes/materials are the standard. As power density increases rapidly, traditional die attaching technology is becoming an increasingly limiting factor in microelectronics packaging for the next generation aerospace and defense systems. This paper introduces an advanced hybrid silver sintering technology, which incorporates ultra-high thermal and electrical performance of silver sintering with high reliability and process friendly of epoxy-based die attach technology. Unlike traditional silver sintering that requires high temperature and pressure, this hybrid sintering paste can be processed without applying any pressures in temperature ranges that are normal in microelectronics packaging processes. This paper presents results of an application study aimed at developing this unique technology in the field of high-power density devices for aerospace applications.