As competition in the semiconductor industry becomes increasingly fierce, Intel has demonstrated its determination to regain its technological dominance with its latest Intel 18A process technology. This advanced process, which is expected to be mass-produced in 2025, is not only the pinnacle of Intel's "Five Process Nodes in Four Years" plan, but also opens a new chapter for chip performance, density and energy efficiency through two major technical highlights: RibbonFET all-around gate transistors and PowerVia backside power supply technology. How do these two "sharp swords" work together to make Intel 18A the focus of the industry? Let's find out!
RibbonFET: The “Full Surround” Evolution of the Transistor
Transistors are the soul of semiconductor chips. As process technology continues to shrink, the traditional FinFET (fin field-effect transistor) architecture has gradually approached its physical limit. Problems such as increased leakage, heat dissipation difficulties, and poor current control have led the industry to seek breakthroughs in the next generation of transistor technology. Intel's RibbonFET gate-all-around transistor (GAA) is the answer to this technological revolution and a major leap forward in transistor architecture.
Technical principles and advantages
The core design of RibbonFET is to evolve the gate from surrounding three sides of FinFET to completely covering the ribbon-shaped transistor channel, forming a three-dimensional "full surround" structure. This design greatly improves the gate's ability to control the current in the channel, making the current run more stable and more accurate. Specifically, the advantages of RibbonFET include the following points:
Reduce leakage and improve energy efficiency
In traditional FinFET, as the size of transistors decreases, the leakage current problem becomes increasingly serious, resulting in increased power consumption and increased heat dissipation pressure. RibbonFET uses a fully surrounding gate to "lock" the current firmly in the channel, greatly reducing leakage. According to Intel's tests, this technology can operate at a lower voltage (for example, a threshold voltage as low as 0.3V) to achieve higher performance per watt, which has a significant power saving effect for devices that need to operate for a long time (such as laptops or servers).
Faster switching speed, explosive performance
The full-surround structure allows the gate to control the current more precisely, thus increasing the switching speed of the transistor. Whether in a high-voltage or low-voltage environment, RibbonFET can provide a stronger drive current, which means that the processor can complete computing tasks faster. This is a big plus for AI PCs or high-performance computing (HPC).
Space saving and design flexibility
RibbonFET uses vertically stacked strip channels, which can fit more transistors in a smaller area and achieve higher density compared to the horizontal stacking of FinFET. What's more amazing is that the channel width can be adjusted according to application requirements, such as narrower for low-power devices and wider for high-performance chips. This flexible design allows RibbonFET to adapt to multiple scenarios from mobile phones to servers.
Proof of the limits of technology
At the IEEE International Electron Devices Meeting (IEDM) at the end of 2024, Intel demonstrated the extreme scalability of RibbonFET: the gate length is only 6 nanometers, and the channel thickness is compressed to 1.7 nanometers. At such a small size, RibbonFET still maintains the industry-leading short-channel effect control and performance, proving its potential in miniaturization. This technological breakthrough not only continues Moore's Law, but also opens up new possibilities for future chip design. For gamers, this means that future CPUs or GPUs will not only run faster, but also save more power, and heat dissipation problems will not be so annoying.
PowerVia: A revolution in power supply from "pizza" to "sandwich"
If RibbonFET is the evolution of transistors, then PowerVia backside power supply technology is another major innovation of Intel in chip manufacturing process. Traditional chips are like making pizza, with all components - transistors, signal lines, power lines - squeezed on the front. As transistors become smaller and smaller, the lines become more and more dense, resulting in endless signal interference and power supply bottleneck problems. PowerVia completely flips this logic and changes it to make it like making a sandwich, moving the power lines to the back of the chip, allowing the front to focus on signal transmission.
Technical principles and advantages
The core concept of PowerVia is to separate power supply from signal. The specific method is to first manufacture the transistor and interconnect layer, then flip the wafer, polish the back side to expose the bottom power supply structure, and embed nano-silicon through-vias (nano-TSV) to connect the power lines. This "back-side power supply" design brings multiple benefits:
Direct power supply, reducing power consumption and interference
Traditional front-side power supply has complex circuits, and the current has to take a long detour to reach the transistor, which is prone to voltage drop (IR drop) and signal crosstalk. PowerVia makes the power supply path super direct, reaching the transistor directly from the back, reducing resistance and interference. Intel tests show that this technology can reduce platform voltage by 30%, effectively improving power supply efficiency while reducing power consumption, which is especially important for servers or AI chips that require stable operation.
Space utilization rate increased dramatically, increasing density
By moving the power line to the back, the space on the front is freed up, the signal line can be laid out thicker and smoother, and the standard cell utilization rate inside the chip exceeds 90%. This means that more transistors can be packed into the same area, and the density is greatly improved. Compared with the traditional process, this is like clearing out a living room that was originally filled with clutter, leaving you with more room for activities.
Frequency increase, performance to the next level
Due to the improved power supply efficiency and enhanced signal integrity, PowerVia brings a 6% frequency boost. For general users, this means that the processor can run faster and respond more sensitively; for high-performance computing, it means stronger computing power output. This performance improvement can also be combined with the fast switching characteristics of RibbonFET to form a perfect complement.
Industry-leading implementation
Intel first implemented PowerVia technology on product-level test chips in 2023, and now it has been fully implemented on Intel 18A. In contrast, TSMC expects to introduce backside power supply in the A16 process in 2026 or 2027, and Samsung plans to implement similar technology in the SF2P process in 2026. Intel's early deployment allows it to lead its competitors in the field of backside power supply by at least one to two years, demonstrating its strong technical strength.
Intel 18A: Performance, density, and energy efficiency win three times
With the support of RibbonFET and PowerVia, Intel 18A has achieved great performance. According to official data, compared with Intel 3 process, 18A has a 15% improvement in performance per watt and a 30% increase in chip density. This means that future processors can pack more transistors into a smaller area, run faster and save more power, achieving a win-win situation of performance, density and energy efficiency.
In actual application, Intel has already used this technology in its own products. Samples of the two processors, Panther Lake for AI PCs and Clearwater Forest for servers, have been shipped and successfully started up and ran the operating system. Mass production is expected in 2025. Panther Lake's DDR memory performance has reached the target frequency, and Clearwater Forest has been combined with Foveros Direct 3D packaging technology to become the industry's first high-density, high-performance solution. These achievements not only make Intel's own products more competitive, but also attract the attention of external customers.
One step ahead of TSMC? Ecosystem and mass production schedule are key
Speaking of competition, of course we have to compare with TSMC. TSMC's N2 process is expected to enter mass production at the end of 2025, and the first batch of products will not be available until 2026. Intel's 18A may enter mass production as early as the first half of 2025, leading by nearly a year. This time difference is a big advantage for Intel, especially at a time when the demand for AI PC and server markets is exploding, being able to take the lead is definitely the key to success.
In addition, Intel is also actively building ecosystem support. For example, major EDA manufacturers such as Cadence and Synopsys have begun to support Intel 18A's design kit (PDK 1.0). More than 35 partners cover design, cloud, and aerospace defense fields, allowing customers to smoothly switch to new processes. In comparison, although TSMC has a stable market share, Intel's comprehensive attack on technology and ecosystems has indeed demonstrated its ambition that cannot be underestimated.
Conclusion: Intel’s comeback?
From the precise current control and high-density design of RibbonFET to the power supply innovation and space optimization of PowerVia, Intel 18A is not only a technological breakthrough, but also Intel's hope to revive its foundry business. The combination of these two swords will take chip performance and energy efficiency to the next level, and also write a new milestone for Intel in the semiconductor world. Although Intel has fallen a lot in the foundry business in the past few years, the progress of 18A makes people see the possibility of a turnaround. If Panther Lake and Clearwater Forest can be successfully mass-produced in 2025, combined with potential customers such as Broadcom and even the rumored NVIDIA, Intel may really be able to rely on this battle to return to the throne of technological hegemony.
For Taiwanese technology fans, the rise of Intel 18A is not just a technology show, but may also be a prelude to a reshuffle in the PC and server markets in the future. Are you ready for this new chip revolution?