SBIR Phase II: Ultrasoft Thermal Interface Elastomer for Microelectronics

Award ID: 2233069

The broader/commercial impact of this Small Business Innovation Research (SBIR) Phase II project is in improving the efficiency and performance of electronic devices. Modern devices, including cell phones, laptops, and electric vehicles contain high-powered semiconductor components which generate unwanted heat that, in turn, reduces their efficiency. If left unchecked, this heat may destroy the devices and even injure users or cause damage to the environment. This project addresses excessing heating in electronic devices by introducing new high-performance thermal interface materials based upon embedding liquid metal droplets inside of stretchable polymers. These so-called liquid metal embedded elastomer (LMEE) materials can be applied to computer processors, graphics cards, advanced artificial intelligence (AI) chips, and even power modules in electric vehicles, to help keep electronic devices operating at peak performance at all times. The growing prevalence of the Internet of Things, 5G network infrastructure, and electric cars all necessitate better thermal solutions so that devices can function properly. This project could contribute to the semiconductor, automotive, and healthcare industries. This projects goal is to develop and commercialize a thermal interface material (TIM) for packaged microelectronics, building upon the LMEE composite architecture. The technology will outperform existing TTIMs by combining the superior thermal resistance of metal-based solid TIMs (S-TIMs) with the mechanical reliability of polymer-based TIMs and the high-volume manufacturing compatibility of thermal greases. Specifically, LMEEs possess a unique combination of metal-like thermal resistance, rubber-like elasticity, and liquid emulsion-like rheology prior to curing, thereby solving two main challenges present with existing S-TIMs: (i) poor mechanical reliability over long durations and (ii) incompatibility with syringe-based dispensing for high volume manufacturing. The strategy proposed in this project is to synthesize an LMEE-based TIM that forms a robust bond between the surfaces of the semiconductor chip and surrounding enclosure, maintains a controlled thickness between the chip and enclosure, and ensures the necessary rheology for syringe-based dispensing. Specific project tasks build around a comprehensive technical plan that includes materials synthesis, performance characterization, and in-package evaluation. In parallel, the project will examine methods for storage, shipment, and dispensing to ensure a product that is ready for integrated device manufacturers and semiconductor assembly and testing industry by the end of this project. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Program Director: Rajesh Mehta