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Abstract The rapid growth of digitization and data-driven technologies is driving large-scale deployment of data centers worldwide. As societies become increasingly inference-hungry, the energy consumption of data centers continues to rise at an unprecedented rate, with a significant fraction of this energy being expended on thermal management and cooling infrastructure. Improving cooling efficiency has therefore become a critical challenge for the thermal management community, directly impacting both the sustainability and scalability of future computing systems. In this paper, we demonstrate an energy-efficient cooling solution based on chip-integrated two-phase cooling, which leverages liquid-to-vapor phase-change heat transfer to achieve high heat-flux dissipation at reduced pumping power and thermal resistance. This paper investigates an aggressive cooling architecture utilizing direct-on-die two-phase jet impingement on an NVIDIA Tesla V100 GPU without any thermal enhancement structures. By eliminating thermal interface material (TIM) and impinging the working fluid R1233zd(E), a low-global warming potential (GWP) (<1) refrigerant, directly onto the silicon backside, the primary thermal bottleneck is removed. Experimental results demonstrate a junction-to-coolant thermal resistance of 0.056 °C/W and a theoretical pumping power of only 0.172 W versus the conventional air-cooled cold plate of 0.1709 °C/W and a fan power of 39.9 W. Furthermore, the reliability of the direct-on-die cooling technique was validated through 200 h of continuous, stable operation. This study positions direct jet impingement as a highly efficient, compact, and sustainable solution for next-generation high-performance computing environments.
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This content will become publicly available on June 1, 2027
Experimental Characterization and Server-Level Demonstration of Confined, Direct-on-Silicon Two-Phase Jet-Impingement Cooling With Additively Manufactured Porous-Wick-Assisted Phase Separation
Two-phase jet impingement cooling is a promising solution for high-heat-flux semiconductor thermal management, as it combines strong convective heat transfer with boiling to remove large heat loads at relatively low flow rates and pressure drops. However, practical deployment is hindered by challenges including inconsistent boiling initiation on smooth surfaces, surface dry-out, vapor-induced flow instabilities, and premature critical heat flux (CHF). Excessive vapor generation within confined geometries can disrupt flow uniformity, causing temperature oscillations and unstable operation. To address these challenges, this work presents a confined, direct-on-silicon two-phase jet impingement cooling approach incorporating a porous-wick-assisted phase separation mechanism. The engineered porous wick enhances nucleate boiling and enables in situ phase separation at the boiling surface. Integrated with a custom three-path manifold, the design routes separated liquid and vapor streams, minimizing vapor accumulation within the confined region and suppressing two-phase instabilities. The porous wick is directly printed onto the silicon substrate using advanced additive manufacturing, eliminating the need for a thermal interface material (TIM) and its associated thermal resistance. Thermal–hydraulic characterization using a low-surface-tension dielectric fluid demonstrates that wick-assisted phase separation reduces thermal resistance by 23–29% compared to configurations without phase separation. Extended testing over more than 200 h of continuous operation confirms stable thermal performance and indicates strong potential for long-term reliability. System-level validation is demonstrated in a 1 U server equipped with an NVIDIA V100 GPU (graphics processing unit) incorporating a direct-on-silicon printed wick.
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- Award ID(s):
- 2209776
- PAR ID:
- 10704496
- Publisher / Repository:
- ASME
- Date Published:
- Journal Name:
- Journal of Electronic Packaging
- Volume:
- 148
- Issue:
- 2
- ISSN:
- 1043-7398
- Subject(s) / Keyword(s):
- direct-on-silicon, two-phase jet impingement cooling, wick-assisted phase separation, additive manufacturing, boiling instabilities
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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