Temperature leveling of electronic chips by solid-solid phase change materials compared to solid-liquid phase change materials

lPassive heat sink using a solid–solid phase change material, vanadium dioxide (VO2).lTemperature leveling performance of VO2 is greater than paraffin based on comparison.lTemperature leveling performance of VO2 is attributed to high thermal conductivity. The complexity and the miniaturization of portable electronic devices has resulted in an increase in the heat generation density, which is a major issue. Passive heat sinks using phase change materials (PCMs) have gained widespread attention as thermal management devices to improve the reliability of the portable devices. Paraffin is a solid–liquid PCM, which exhibits relatively large volumetric latent heat and is typically used in passive heat sinks. However, it faces certain limitations such as low thermal conductivity and liquid leakage due to melting. Vanadium dioxide (VO2), which is a solid-solid PCM, has a high thermal conductivity and large volumetric latent heat. Therefore, VO2 can potentially be used to overcome the issues of the conventional PCMs such as paraffin. This study aims to determine the feasibility of a passive heat sink using VO2 by evaluating the temperature leveling performance when VO2 is attached to a heat source. The same evaluation is performed for the paraffin for comparison. From the experimental results, it is observed that VO2 exhibits a higher temperature leveling performance than paraffin. Furthermore, the effect of each thermophysical property of the PCM on the temperature leveling performance is evaluated through numerical simulations. The simulation results highlight the advantages of using VO2 as the PCM for a passive heat sink.