Intel’s future bet for performance: stacking transistors

Welcome to the future.

intel stacking transistors
Image via Intel

AMD’s 3D stacking isn’t too far away, but Intel has already provided a window into where CPU technology might go next: stacking transistors.

Intel’s Research Components Group announced a roadmap for the next ten years at a conference in San Francisco. One of the company’s new innovations was a research paper into a method for stacking transistors, something Intel argues could improve transistor density by as much as 50 percent.

Processor chips have traditionally been flat, with all the transistors sitting level with each other. The new method stacks additional chicklets on the existing design to increase the transistor count without requiring a larger surface area. 

“By stacking the devices directly on top of each other, we’re clearly saving area,” Paul Fischer, Director and Senior Principal Engineer at Intel’s Components Research Group, told Reuters. “We’re reducing interconnect lengths and really saving energy, making this not only more cost efficient, but also better performing.”

Current chips rely on two types of transistors that are laid out side-by-side, but by bonding the transistors on top of each other and bonding them in the same process, Intel may also be able to manufacture chips a little more quickly.

Intel’s biggest rival, AMD, already has a similar design solution called 3D V-cache implemented in the Zen 3 refresh and forthcoming Zen 4 CPUs. AMD’s solution is slightly different because it only stacks the L3 cache, not the transistors themselves. 

It’s worth noting that Intel’s stacked transistors won’t appear for several years. The first major change in transistors will arrive in 2024, when Intel is due to replace their transistor architecture with RibbonFET.

RibbonFET isn’t the only advancement on Intel’s roadmap. The company is also looking to introduce a new power delivery process called PowerVia as part of its 20A manufacturing process, according to PC Mag. Chips manufactured on Intel’s 20A process aren’t expected to launch until 2024, with Intel’s 2023 CPUs the company’s first to be made using high numerical aperture extreme ultraviolet lithography.