<p>➀ MIT Lincoln Laboratory developed a specialized chip to test cooling solutions for 3D-stacked microelectronics, addressing overheating challenges in high-power density systems.</p><p>➁ The chip generates heat (up to kilowatts/cm²) to mimic real chip behavior and measures temperature changes through embedded "tiny thermometers," enabling precise cooling efficiency evaluation.</p><p>➂ It replicates both distributed heat and localized hot spots in 3D stacks, helping researchers optimize thermal management for buried layers and validate methods like liquid microchannel cooling.</p>