Here is the abstract you requested from the thermal_2015 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|A Low Thermal Resistance and Highly Durable Carbon nanotube-polymer composite Thermal Interface Material for Burn in and Device Testing Applications|
|Keywords: Thermal Interface Material, Burn In, Testing|
|Integrated circuit manufacturers attempt to induce eventual failure during an infant mortality period through a combination of “burn-in” and stress testing on their chips. In burn-in testing, chips are exercised at elevated temperatures, taking advantage of the inverse relationship between reliability and operating temperature. Because the devices are being exercised at their performance limits during testing, an effective thermal interface material (TIM) is a must. The desired characteristics of TIMs for burn in applications are: low thermal resistance, high mechanical compliance, high robustness, and leaving no residue on the chips. In this work, a carbon nanotube- polymer composite TIM is investigated as a potential solution to this difficult thermal problem. Vertically aligned carbon nanotubes grown on metal foils can deliver low thermal resistances due to their high in plane conductivity, mechanical compliance and achievable contact area for heat transfer. Then, a polymer can be infiltrated into the CNT array to further improve the TIM’s thermal and mechanical properties. By displacing the air inside the array, thermal resistances as low as 0.5 cm2K/W are demonstrated. Furthermore, careful selection of the polymer’s hardness, compression set, thermal stability, and shear strength, gives the resulting composite the durability needed for burn-in applications. With these enhanced thermal and mechanical properties, the TIM maintains its low thermal resistance for over 2000 thermo-mechanical test cycles. Finally, the composite material’s compliance and low compression set allow the size of the device under test to be changed in concert with the demands of the production schedule without the need to change out the TIM.|
Georgia Institute of Technology