Advanced microelectronics are moving on from the Moore's Law era to be More-than-Moore. Denser chips have higher internal and external clock rates, and higher power dissipation.
This generates more heat, which then has to pass through the packaging material. The chips are so dense that they heat up within milliseconds. The heat dissipation of the die and package is much slower. So hot spots will develop, which become unusable, until it cools down enough to use it again. This pushes the capabilities at all packaging levels, and ultimately limits the performance.
Figure 1: Maximum operating temperature of commercially available TIM, which cannot keep up with modern requirement. Source: IDTechEx Research
Packaging innovations are essential in meeting the conflicting requirements of system densification and processing acceleration. In order to accomplish these goals, new materials, including Pressure-Sensitive Adhesive Tapes, Thermal Adhesives, Thermal Greases, Thermal Gels, Pastes and Liquids, Elastomeric Pads, Phase Change Materials, Graphite, Solders and Phase Change Metals, Compressible Interface Materials, and Liquid Metals, are being developed. More information on the available thermal interface materials and innovations in this industry can be found in the IDTechEx Research report Thermal Interface Materials 2015-2025: Status, Opportunities, Market Forecasts.
Novel interconnect structures and innovative materials can be developed to meet these challenges. New macro-, micro- and nano- structures will be needed. Nano-particles and Nano-structures are being integrated into thermal interface materials to improve material properties. Innovative materials can higher thermal conductivity, higher compliance and higher temperature stability.
Nanostructured conducting particle fillers include, Carbon Nanotubes, Graphene, 2D Boron Nitride, Metallic Nanoparticles and Shape Memory Alloy (SMA) fillers such as nano-CuNiTi, nano-CuAlZn and nano-NiTiAlZn. Nanostructured fillers have a much higher cost per kilogram, but generally require a much lower loading to give equal improvements in conductivity, so have a more favourable performance-to-cost ratio than might be expected.
Personal computers are no longer the driver in the semiconductor industry. Smartphones are now responsible for 27% of all ICs sold but even this market is slowing. The new wave is the Internet of Things. This is a full ecosystem that covers materials to systems and includes smart homes, smart cities and smart factories. It doesn't always need the most advanced technology. It does require a wide variety of power density, form factor and cost. There are emerging solutions for denser, faster, smaller, thinner and more conforming microelectronics in communicating, computing, sensing and interlinking devices and systems. These are solutions to the growing connectivity problems facing microelectronics designers, fabricators, assemblers and integrators. For detailed discussions, join us at Internet of Things Applications USA
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