Ultrahigh Energy-Dissipation Thermal Interface Materials through Anneal-Induced Disentanglement

Abstract

Thermal interface materials (TIMs) that function as reducing the contact thermal resistance between chip and cooling solution are indispensable in modern electronics. The development of electronics toward reduced feature size and being wearable has led to the need for new TIMs with both heat dissipation and high energy dissipation. However, the strong coupling between storage modulus and energy dissipation makes it difficult for TIMs to acquire these two properties simultaneously. Here, we propose an anneal-induced disentanglement strategy to obtain excellent heat dissipation properties of TIMs in a vibration environment, which is difficult for traditional TIMs. The dissociation of partially introduced dynamic covalent bonds in the polymer matrix releases the trapped entanglement and reduces storage modulus during the annealing process. Using prototypical dynamic thioester cross-linked polybutadiene adducted with maleic anhydride (PAMA), we achieved thioester-TIMs with tan δ higher than 0.94 in the frequency range of daily life, which is 4.7 times higher than that of traditional TIMs. In the actual application of 10 Hz vibration frequency, no temperature fluctuations (∼0 °C) are detected when using the thioester-TIMs chips, while the use of traditional TIMs show fluctuations of ∼3 °C. Such excellent performance creates new opportunities for TIMs design, and addresses current limitations in TIMs for flexible electronic packaging.

Interfacial Coordination Interaction Enables Soft Elastomer Composites High Thermal Conductivity and High Toughness

“…Soft elastomers consisting of long polymer chains cross-linked through covalent interaction have been widely used in multiple applications, such as soft electronic devices and soft robotics, mainly due to their ability to undergo large deformation with a small external force. − Many systems require the elastomers have high toughness to dissipate much energy to resist the extension of cracks. However, the fast development of electronic devices toward miniaturization needs the soft elastomers with high thermal conductivity to dissipate accumulate heat. − For example, thermally conductive elastomers are often used as thermal interface materials, used between the chip and the heat spreader, and play indispensable role in effective heat dissipation of chips. However, most elastomers suffer from a poor toughness and thermal conductivity, which limits their use.…”

Soft Composite Gels with High Toughness and Low Thermal Resistance through Lengthening Polymer Strands and Controlling Filler

“…To demonstrate the potential application in heat dissipation of electronic devices, we employed the T3Ster method to evaluate and compare the heat dissipation ability of our composite gel CE-2-80 and a commercially-available TIM (thermal conductivity of 7.5 W m −1 K −1 and thermal resistance 1.651 cm 2 W −1 at 10 psi pressure) in a thermal test chip (10 mm × 10 mm) (Figure 5D). [36,37] The thermal power consumption of the chip was set up to 6.42 W cm −2 , and the ambient temperature is 25 °C. As shown in Figure 5E, when the current is switched on, the chip temperature rises rapidly.…”

The Synergy of Hydrogen Bond and Entanglement of Elastomer Captures Unprecedented Flaw Insensitivity Rate

“…[2] Thermal interface materials (TIMs) are commonly employed to fill between heat-generating components and heat-dissipating components to improve the heat dissipation capability. [46][47][48][49][50][51][52][53] Thermal resistance is the most intuitive parameter to evaluate the heat dissipation capability of TIMs. [54,55] In order to enhance the heat dissipation capacity, we fabricate the B-H-P 0.151 -based TIMs (BHP-TIMs) by mixing the B-H-P 0.151 elastomers and microscale spherical aluminum (Al).…”