论文标题
液冷3D-IS的热应力分析
Thermal Stress Analysis of Liquid-Cooled 3D-ICs
论文作者
论文摘要
众所周知，如果没有将其冷却到合理的工作温度，则3D-ICS患有热点温度可能达到数千度。热点的问题不仅限于IC的高温；即使在冷却芯片后，热应力也会构成严重的问题。这项研究研究了由3D-IC热点产生的热应力，该热点具有20 W功率耗散。使用SIO2和钻石冷却块冷却IC。该研究是使用三种冷却液体进行的：水，Freon（R22）和液氮（LN）。正如预期的那样，研究表明，芯片上的金属层由于将芯片温度升高至高于室温的值而遭受高热应力。还注意到，如果使用LN进行冷却，则应力变得更加严重。实际上，应力超过了铝的最大拉伸强度，这意味着芯片的故障。这表明冷却3D-IC可能无法确保可接受的操作或可靠性。必须在高温和低温下研究热应力，以确保高性能和可接受的可靠性。
It is known that 3D-ICs suffer from hot spot temperatures that can reach thousands of degrees, if they are not cooled to reasonable operating temperatures. The problem of hot spots is not limited to the high temperatures of the IC; thermal stress can also pose severe problems, even after cooling the chip. This study investigates thermal stress resulting from a 3D-IC hot spot with 20 W power dissipation. The IC is cooled using SiO2 and diamond cooling blocks. The study is performed using three cooling liquids: water, Freon (R22), and Liquid Nitrogen (LN). As expected, the study shows that metal layers on the chip suffer from high thermal stress due to rising the chip temperature to values higher than the room temperature. It is also noticed that the stress becomes more severe, if cooling is done using LN. In fact, the stress exceeded the maximum tensile strength of aluminum, which means failure of the chip. This indicates that cooling 3D-IC may not ensure acceptable operation or reliability. Thermal stress must be investigated at both high and low temperatures to ensure high performance and acceptable reliability.
