Reliability Studies of a Super-Durable 3-D-Foam-Based TIM for All Environments

With the current trend and need of devices to thrive toward higher performance and faster operational speeds, while shrinking in size and weight, harsh and stringent conditions are also expected from their thermal-management capabilities. An important role in maintaining these devices at a safe operational temperature is fulfilled by thermal interface materials (TIMs). However, even state-of-the-art TIMs are reaching their limits in terms of operational temperature range and reliability, with the tendency to “pump-out” as well as “dry-out” during temperature cycling, which tremendously decreases its thermal performance and, thus, leads to failures in thermal management of the device overall. Worse, with the demand of operation at higher and higher temperatures, these failures often occur sooner and more frequently, leading to failure of the TIM before the end of the lifetime of the device. In order to deliver a higher performance TIM, capable of withstanding higher temperatures, we have recently presented a new class of nano-TIM, “3-D-foams.” These foam-like structures are composed of multilayer domains of 2-D-graphene and h-BN; they have a very high thermal conductivity, high surface conformity, and are tailorable for different electrical conduction needs. In this paper, we further studied these nano-TIMs and assessed their reliability under thermal cycling, according to JEDEC Standard JESD22-A104D, and high temperature/humidity environment, following JEDEC Standard JESD22-4118, to evaluate whether their performance can be translated into practical operating conditions of electronic devices. Results show that these 3-D-foams are able to maintain their high performance throughout all strenuous conditions they were exposed to, without any loss in chemical and physical composition, as well as thermal properties. A shelf life of over 400 years under normal office conditions, and more than ten years for extreme humid conditions was extrapolated, as well as an operational lifetime of over ten years in consumer electronics, which far exceeds normal lifetimes of current electronic appliances. These results demonstrate that this new class of nano-TIM is capable of not only outperforming state-of-the-art TIMs but is also a viable candidate to withstand current and future needs of operational temperatures and lifetimes of new electronics.