Heterogeneous Integration for Al Workloads

Semiconductor scaling to smaller dimensions has led to tremendous improvement in electronic systems performance. Computer systems that used to occupy several rooms are now available in the palm of your hand. However, as semiconductor scaling saturates, other paradigms are necessary for improving the systems performance. One such paradigm of performance improvement is advanced packaging of heterogeneous chips from different semiconductor nodes, different construction and different sources - often called heterogeneous integration (HI). HI is necessary because system performance is required to grow 1000x over the next 7-10 years, especially for Artificial Intelligence (AI) applications. A subset of AI, called machine learning, relies of artificial neural networks that simulate a human brain. In this talk, we compare and contrast the different HI packaging options which include conventional 2D single-chip and multi-chip packages with high-density laminates, package-on-package (PoP) configurations, 2.5D silicon interposers, silicon bridge packages, and fully 3D stacked packages. Many of these configurations are being developed in the IBM AI Hardware Research Center (AIRC). We then elaborate on the Direct Bonded Heterogeneous Integration Si-bridge packaging scheme.

Bio: Kamal Sikka is a Senior Technical Staff Member at IBM. He joined IBM after obtaining his PhD degree in Mechanical Engineering with a focus in Thermal Sciences from Cornell University. His initial work at IBM focused on thermal solution development, e.g., thin-gap thermal paste technology, for IBM OEM customers such as Compaq/HP. This was followed by IBM server thermal solution development such as an Adhesive Thermal Interface coupled to SiC and Diamond heat spreaders.

Kamal then took on the management of the IBM Packaging Development Thermal Development and Modeling department. He transformed the Advanced Thermal Lab with introduction of multiple automated thermal chip-package testers and initiated the Mechanical Analysis Lab as the package substrate technology transitioned from ceramic to organic laminate materials. His team delivered multiple advanced thermal solutions for IBM Systems such as advanced TIMs, diamond heat spreaders, dual heat spreaders and package integrated heat sinks. He was also the leader of the thermal qualification teams for IBM's ASIC menu packages from Cu08, Cu65, Cu45, Cu32, and FX-14 technologies. Besides developing thermal solutions, Kamal led the IBM package modeling and simulation teams, developing modeling protocols for IBM's laminate package technology. Kamal also led task forces for resolving the Microsoft Xbox issues on a consultancy basis, and solder interconnect delamination in workload simulator systems.

Subsequently Kamal served in the senior manager role for the Packaging Development team with Unit Process responsibilities spanning from C4, CPI, laminate, Bond & Assembly and thermal development. Under his leadership, the team reduced the C4 pitch for IBM server packages, co-developed an advanced TIM with an industrial partner, and conducted fundamental research on glass interposers.

Kamal then transitioned from IBM Systems to IBM Research initiating the Heterogeneous Integration (HI) effort and defining the HI strategy. He has led the establishment of the HI Lab at Albany NY. The HI lab integrates material characterization, thermal analysis, mechanical analysis, Bond & Assembly, and reliability equipment in one location. He is also the technical leader for IBM Direct Bonded Heterogeneous Integration (DBHi) Si-bridge and stacked Si-microcooler technologies.