TAG: GS 3: SCIENCE AND TECHNOLOGY
THE CONTEXT: Researchers from the Indian Institute of Technology, Bombay (IIT Bombay) and the Centre for Materials for Electronics Technology (C-MET), Pune, have developed an innovative alternative to copper cold plates using Low-Temperature Co-fired Ceramic (LTCC).
EXPLANATION:
- LTCC technology is typically used to manufacture ceramic substrates for circuits, which allow compact three-dimensional packing, making them smaller and more efficient compared to traditional printed circuit boards (PCBs).
Heat Management in Computing Devices
- Heat is an inevitable byproduct of the operation of computing devices, including laptops, smartphones, and other electronics.
- The heat generated from prolonged use in demanding tasks such as gaming can lead to significant thermal buildup.
- This not only causes inconvenience to users but also poses risks to device performance and hardware integrity.
- Managing this heat is crucial for maintaining the optimal functionality of the device components, such as integrated circuits, resistors, and capacitors.
- For high-performance systems like supercomputers, advanced cooling solutions are essential to ensure stability and performance.
Traditional Cooling Solutions: Copper Cold Plates
- High-performance computing systems (HPCs) and supercomputers often use liquid cooling methods, where liquid coolants like deionised water are circulated to dissipate excess heat.
- Copper cold plates are traditionally employed in these systems due to their excellent thermal conductivity, low cost, and effectiveness as heat sinks.
- However, copper cold plates have certain limitations, including their weight, susceptibility to corrosion, and challenges in implementing intricate designs.
Advantages of LTCC Technology
- Compact and Efficient Design:
- LTCC substrates are known for their ability to endure high temperatures and are extensively used in automotive and defense equipment.
- They allow for a more compact and efficient design of electronic circuits.
- Microfluidic Channels:
- The study demonstrated that microfluidic channels could be integrated into an LTCC package to form cold plates.
- These channels enable efficient cooling by allowing coolant to penetrate deep into the chip package, providing localized cooling of hot regions.
Overcoming LTCC’s Thermal Conductivity Challenges
- LTCC has significantly lower thermal conductivity compared to copper, which posed a challenge for its use in cooling systems.
- To address this, researchers incorporated thermal vias—tiny holes filled with metal—into the LTCC cooling plates.
- These thermal vias improved the thermal conductivity and reduced thermal resistance by 43%.
Addressing Structural Challenges
- Being a ceramic material, LTCC is prone to cracking under uneven tensile loading.
- To prevent this, a novel clamping mechanism was developed to ensure the cold plates remain intact without experiencing uneven cracking during full loading.
Performance Testing and Results
- The LTCC cold plates were tested on an Intel® Xeon® Gold 6154 CPU using deionised water as the coolant.
- Two flow patterns, JI and MC, were tested to determine their effectiveness:
- MC Flow Arrangement: The coolant enters from one side and exits from the other, allowing the coolant to flow the entire length of the cold plate.
- JI Flow Arrangement: The coolant enters from the center inlet and exits from the two side outlets, providing localized cooling of hotspots.
- Both flow patterns successfully kept the processor temperature below the safety limit at full processor power.
Future Prospects
- The current LTCC cold plates are designed for a 200 W processor range.
- Future improvements could include electroplating the base of the cold plates to enhance heat spreading, potentially allowing them to accommodate higher heat inputs.
- If commercialized successfully, LTCC-based integrated cold plate technology could revolutionize current cooling systems and chip packaging used in high-performance computing.
