Inside Intel's Fabs: How New Chip Technologies Reach Production, and Why Tools May Cap AI's Compute Supply

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Overview

Dwarkesh Patel spent two days touring Intel's fabs and research labs, then interviewed several of the company's technical leaders. He was pursuing two questions. The first was what it takes to build the world's most advanced chips, and what those chips might look like decades from now. The second was how the semiconductor industry can respond to what he calls the biggest demand shock it has ever faced: the surge in demand for AI compute. One Intel voice at the start of the episode describes AI demand as "easily 40-50% above our maximum capacity, which I've never seen before."

31 min read

Patel's framing is that AI progress has depended on exponentially growing compute. Foundries can sustain that growth in two ways: by making more chips, and by making each chip more capable. Both are limited by equipment Intel buys from suppliers, most famously ASML's EUV lithography machines. The conversations that follow cover both halves of the problem. Process engineers explain how a new node is developed, researchers show transistor and wiring ideas that are still years from production, and Intel's CTO describes how far production can actually grow.

0:49

Bringing up a node: 2,000 steps and a constant hunt for defects

Patel first spoke with Chris Auth, who leads development of the processes Intel currently has in manufacturing. Patel wanted a concrete account of what happens between now and the launch of 14A, Intel's next major node, two or three years away.

Auth said 14A has been in development for "about three-plus years." It is now close to having its process finalized. The team is settling the tool sets it will run on and fine-tuning each process step. A wafer passes through roughly 2,000 steps in the factory. Each one has to be tuned carefully enough that the process can run thousands of wafers a week and give the same result every time.

When Patel asked how yield actually improves from month to month, Auth described two main ways of finding defects. The first is inline metrology: tools inspect wafers during processing and flag defects as they appear. The second happens at the end of the line, where electrical test and sort show which chips fail. Engineers then analyze those failures, often by cutting a cross-section and imaging it in a transmission electron microscope (TEM) lab like the one Patel had visited. A cross-section might show that a defect sits between two particular layers. That points to a specific section of the process flow, and engineers can then match it against the inline metrology data from that section to decide which defects to go after.

2:59

The lessons of 10 nanometer

Auth tied Intel's current approach to a hard lesson: "you don't want to do too much innovation in one node." Each new idea adds complexity. You may eventually get it all working, but customers need a predictable schedule, so the real question is how much innovation fits inside the timeline they need.

The narration explains why Intel takes this so seriously. Intel's 10nm node was originally targeted for 2016 but did not begin manufacturing until 2018. The episode includes period news clips about Intel losing its two-year cadence and its stock falling while TSMC's rose.

Auth said that 10nm was meant to deliver "hyperscaling," shrinking much faster than Intel historically had. The tools needed for that kind of shrink weren't ready, so the team invented many workarounds that let them hit the targets with existing tools. That put a heavy burden on both the process and the engineers. Auth maintained that 10nm ended up "a great technology" with world-class yield, performance, and cost, but it took longer than Intel wanted. The takeaway has been to limit how much innovation goes into each node so it stays on schedule.

When Patel asked which technology should have been saved for a later node, Auth singled out EUV. When Intel defined 10nm, it concluded EUV was not ready. The narration explains that EUV prints patterns with 13.5-nanometer light, about 14 times shorter than the wavelength used by earlier tools, and shorter wavelengths can print finer features in one exposure. TSMC moved sooner. It put EUV into volume manufacturing in 2019 and expanded its use on 5nm in 2020. Intel's first EUV process did not reach products until 2023, which gave TSMC about four more years of experience with the machines.

Another outcome of 10nm, according to Auth, was a set of formal "maturity metrics" used in a "phase gate" process. To move from pathfinding into development, a technology has to meet defined yield, defect, and performance criteria. A technology that misses the bar is deferred to a later node. The priority is staying on schedule.

6:43

From planar transistors to gate-all-around

The narration explains why staying on schedule is hard: new transistor designs take decades to mature. Modern transistors descend from the planar MOS transistor demonstrated in 1960. Patel frames their history as a progression from two dimensions into three.

A transistor is a switch. Current flows between the source and the drain when a gate sitting above the silicon is turned on. A positive voltage on the gate pulls electrons up toward it. A thin insulating layer stops them from reaching the gate, so they collect just beneath it and form a conducting channel. As transistors shrank, the source and drain got so close that current leaked through even when the switch was supposed to be off. The fix was to have the gate grip the channel from more sides. The planar transistor's gate touches the channel only from above. A FinFET squeezes the channel into a vertical fin, so the gate wraps it on three sides. Gate-all-around (GAA) slices the channel into thin ribbons, and the gate wraps each one completely.

Building GAA required new materials and new steps. The silicon ribbons are first sandwiched between layers of a temporary placeholder material. The real gate materials can't survive later processing, which includes baking the wafer at around 1,000°C. Once the hot steps are done, the placeholder is etched away and the ribbons are left suspended. The gaps are then coated with a high-k insulator, which lets the gate pull more strongly on the channel, and the gate metal goes on top. The narration points out that FinFET was demonstrated in 1989 and reached volume production at Intel in 2011. A GAA transistor was demonstrated a year earlier, in 1988, yet Samsung didn't start producing GAA chips until 2022. The two ideas emerged together but reached production a decade apart.

Auth's explanation for the delay was partly strategic. The industry had known about GAA since the '90s, and it also knew GAA would be hard to manufacture at volume. Meanwhile, other options could still deliver performance: strained silicon, high-k metal gate, FinFETs. "You don't want to tackle something before you have to." Only after those were used up did GAA, which Auth called "really the ultimate transistor," become worth the effort. Then the real work began, such as figuring out how to integrate high-k metal gate with GAA. Some of that work requires new materials. Some requires inventions from tool vendors: a tool that can do a particular operation, a gas that deposits a particular material, a heating chuck with particular characteristics. Some of it is plain iteration: build a GAA transistor, see it fail, revise the hypothesis, and try a different structure.

11:31

A "golden age of innovation" after Dennard scaling

Patel asked whether R&D itself changed once simple shrinking stopped delivering. Auth said that in the '80s and '90s, progress came from Dennard scaling and lithography. Things got smaller, transistors got faster and more reliable, and the cadence was predictable. The guiding principle back then was "try to not change anything." Around the 2000s that stopped being enough. In Auth's words, what followed was "this golden age of innovation": strained silicon, high-k metal gate, FinFETs, GAA, and backside power, all changes that engineers in earlier decades would have refused to touch.

For a self-described "transistor junkie," Auth said, this is exciting because "the playbook's open." He estimated that the number of materials used in chipmaking has "probably gone up 10X" since the '90s, and pointed to techniques such as atomic layer deposition that control material atom by atom. His summary was that the attitude is now: "Take the sledgehammer and start tearing the thing up and come up with some new idea."

13:22

Why High-NA EUV pays off for Intel but not TSMC

For 14A, Intel is adopting High-NA EUV. According to the narration, it uses the same light as standard EUV but changes the optics, raising the numerical aperture from 0.33 to 0.55, so features about 1.7 times smaller can be printed in one pass. When a pattern is finer than a tool can print in one pass, chipmakers split it across two, three, or even four exposures. Each extra pass takes time on a machine costing around $200 million and adds another chance for defects. High-NA machines cost roughly twice as much. Whether they are worth it comes down to how many passes they save and how much defect risk they remove.

TSMC has said High-NA doesn't make economic sense for it yet. Auth said the two companies reach different conclusions about the same tool because their architectures differ. Intel uses backside power, which relaxes the pitch requirements on the front of the wafer enough that those layers can be printed directly with High-NA. Without backside power, TSMC has to run tighter pitches, which High-NA can't print in one pass, so it would still need double-patterned EUV. "For them, it's not very helpful. For us, it is very helpful."

The narration explains backside power. A chip has thick power lines and thinner signal lines, and the signal lines must be spaced apart to avoid interfering with each other. Traditionally, all of this wiring is crowded above the transistors. Intel's newest process moves the power lines beneath the transistors, to the back of the wafer, which frees space on top so the signal lines can be less tightly packed. That is why a single High-NA pass is enough for Intel.

Even so, Auth said High-NA is an option at 14A, not a requirement. Intel will discuss it with each customer because it brings both value and added complexity. It is listed in the process design kit (PDK) as an option.

16:25

Learning to be a foundry: the PDK problem

Patel brought up public reports that Intel's 18A PDK had problems, including instructions that didn't work, which made the foundry hard for outside customers to use. A PDK, the narration explains, is the menu of what a process can build and the rules for building it.

Auth acknowledged a learning curve that he said competitors also went through. For decades Intel was an integrated device manufacturer (IDM). Its process teams shared transistor data informally with its own product teams, with no formal PDK process. "18A started out not having a PDK." Customer feedback about the quality, maturity, and content they expected has since been folded in. Auth said 14A will have high-quality PDKs "from the get-go," with maturity levels (0.5, 0.9, 1.0) defined much like the process maturity metrics.

The narration suggests a broader point. Because Intel's fabs historically made only Intel chips, TSMC may have had an advantage from serving many customers: more wafers to learn from, more revenue to reinvest, and more pressure to meet deadlines.

19:22

Could the tech tree have turned out differently?

Patel asked whether a different history could have produced a completely different branch of chip technology, perhaps one without copper wiring at all. Auth thought the arrival at GAA was "somewhat inevitable," since it was already under discussion in the '90s. Backside power is more surprising: the idea of stripping off the entire silicon substrate and putting wires on the back would have seemed "a little bit out there" back then. He considers copper the best wire for larger lines, but expects it to be replaced at the very tightest pitches.

Auth was most interested in what GAA and backside power open up. A transistor is now "floating in interconnect" rather than sitting on a substrate with everything stacked above. That invites the question of why you couldn't alternate transistors and interconnect layer after layer, building one 3D structure instead of stacking separate chips. NAND memory already does this, and Auth thinks DRAM "inevitably" will too. He argued that the industry limits itself by asking only what can be done in the next four or five years: "Let's put 10 years, 20 years. In 2045, do you think you could do it?" At that horizon, he said, quite exotic structures look plausible. His usual answer about scaling is that there is about four years of visibility. At each four-year point you can see another four years, but 10 years out is hard to predict.

The narration connects this to CFET (complementary FET). Chips pair n-type and p-type transistors, which today sit side by side. Stacking them vertically could in principle double density in the same area, but every added layer brings more steps, more cost, and heat with no clear escape path. Patel asked whether heat is the fundamental limit, since logic burns more power than memory and can't be stacked as easily as HBM or 3D NAND. Auth listed three limits on compute: switching speed, the energy per switch, and dissipating the resulting heat. He said these problems are 20 years old, but 3D devices make thermals sharper. System-level analysis and simulation tools for this are "in its infancy." Thermals are and will remain a limiter, he said, but they are solvable.

23:48

The Hot Topics meeting: urgency, risk, and epi nodules

Engineering time and experimental wafers are finite, so deciding where to spend them is one of the hardest parts of bringing up a node. Patel sat in on Intel's "Hot Topics" meeting about improving 18A and 18A-P, then spoke with Kevin Fischer, who ran it. Patel described engineers presenting experiments and ideas, and Fischer and the integration engineers telling them what data they needed and how to move faster.

Fischer said the average engineer lacks visibility into how much their work affects Intel's bottom line and its customers. Engineers often have a fixed set of criteria they want to meet, and when a request is refused they tend to stop there. A key lesson of the industry, he said, is that "you will never have a complete data set. If you want to wait for a complete data set, you've waited too long." Much of his role is deciding how much risk to accept, including whether to start risking production and therefore revenue. He joked that he worried about coming across as an "ogre," and said the point is to convey urgency: "Every day counts."

His example was epi nodules. Epitaxy grows new crystal on an existing surface by flowing gases over a heated wafer. Here it is used to grow the source and drain as small crystals on either side of the gate. During deposition, abnormal growth sometimes appears, "a little thing like a tumor" that grows very fast. It can short one epi region to another and break transistors. The meeting considered a special clean that would remove nodules after they form, and also discussed eliminating whatever causes them. Since the easiest fix is often unclear, Fischer said, the teams work on all potential fixes in parallel, and the one that works is "sometimes not the one you expect first." Once something is identified as a primary problem for the technology, Hot Topics directs resources to it.

Priority wafers can also move faster through the factory using a tiered system of "hot boxes." The highest tier, HotBox 1, gets priority at every tool. Fischer said factory managers dislike using it because it uses tools inefficiently and slows the whole factory. He compared it to clearing every car out of a highway lane so a single experiment can race through.

29:53

Ruthenium wiring, and the cobalt detour

At the research lab, Jack Kavalieros showed Patel ideas that aren't ready for a node yet, beginning with interconnect: the more than a dozen layers of metal wiring above the transistors. Patel asked why Intel is exploring ruthenium when its resistivity is higher than copper's.

Kavalieros explained that copper needs a liner, which he compared to a glue or transition layer, so the copper sticks and connects to the lines below it. As wires shrink, this resistive liner takes up a larger share of the conduction path. Ruthenium can be etched directly, so it doesn't need a liner. At very fine dimensions, giving up the liner wins, and Kavalieros put the crossover at roughly a 20-nanometer pitch, meaning about 10 nm of metal and 10 nm of insulating dielectric. But liners have also been getting thinner over time, which has brought copper "back into play as a contender."

Patel noted that on 10nm Intel moved from copper to cobalt, which reportedly caused problems. Kavalieros said a material has to be both scalable and integrable into a very complex system. When Intel chose cobalt, it was the front-runner with the stronger results. Later work with materials and tool vendors produced solutions that made copper stronger again. "The leading option at the time was cobalt. Now it's copper again, and perhaps in the future it'll be ruthenium." Every node evaluates several options, and a decision is forced as manufacturing approaches.

32:47

CFET in the lab: why a working device is still years from your phone

Patel asked how far CFET stacking can go: two layers, three, four? Kavalieros said the evaluation is underway at Intel, at competitors, and at outside labs, and called CFET "the ultimate in stackability." Stacking relaxes the pressure to keep compressing transistors, but stacked transistors still have to be connected. Connections that used to run on top, or on the bottom with backside power, now have to run vertically between devices. That means etching ever deeper, narrower trenches and filling them without leaving air gaps or voids. Intel is working with vendors on both problems.

Patel asked what currently works in the lab. Kavalieros described "short-loop vehicles." A full manufacturing run can take a month or more through thousands of steps, so researchers take unit cells of the process, such as a diode or a capacitor, and qualify them quickly by measuring electrical and chemical parameters. As those pieces improve, they are combined into more complex test vehicles, eventually a full transistor. A lab CFET might use a single ribbon for the NMOS stacked on a single ribbon for the PMOS, instead of four on four, because taller stacks make aspect ratios harder. The lab can still work at production-scale feature sizes, Kavalieros said. It can deposit one-atom-thick 2D materials (transition metal dichalcogenides), test their conductivity, contacts, and modulation, and print fine features with EUV or e-beam.

So why would CFET take a decade to reach a phone? Kavalieros said the answer differs for materials and for architectures. A material has to be shown to deposit, etch, and remove correctly, and to be compatible with the layers above and below. An architecture looks like a simple evolution ("what's wrong with just stacking them?"), but stacking raises the aspect ratio for etches, depositions, and cleans, and the tooling may not be ready. The simplified lab version may not beat today's side-by-side nanoribbons. It has to evolve, perhaps to two ribbons and with the right metals and dielectrics, before it outperforms the prior technology. "There's a thousand different steps that all have to come together."

Asked where ideas fail, Kavalieros gave examples. A film might deposit and measure well, but "the moment I try to make a contact to it, nothing sticks," so a material can be ruled out over something as basic as adhesion. Harder failures appear later: capping layers that aren't hermetic, so a third, fourth, or fifth process step still reacts with the film and changes its properties. If no better seal can be found, "it's a dead end for us."

39:57

Hybrid bonding and the chip-to-chip bottleneck

Stacked transistors are still in research. Stacked chips are already in production, and they address a different problem. The narration notes that Nvidia's Blackwell data-center GPU joins two large processor dies and surrounds them with eight HBM stacks, and that in AI the speed of data traffic between chips, not the raw computation, often limits performance. Patel describes this as an area-versus-perimeter problem: doubling a chip's width and length quadruples its area but only doubles its edge. As density rises, compute grows faster than the ability to move data.

The narration traces how packaging evolved: chips side by side with wires at their edges; "2.5D" packaging, where chips sit on a shared silicon interposer; direct chip-on-chip bonding with solder bumps, which are bulky and resistive; and finally hybrid bonding. In hybrid bonding, the copper contacts of two chips are aligned, pressed together, and heated so the copper expands and fuses while the surrounding insulator also bonds. Removing solder allows much denser connections. The narration says it reached volume manufacturing only after alignment and defect problems were worked out.

Tyler Osborn, a director in Intel's advanced packaging technology development group, compared two approaches. Wafer-to-wafer bonding joins two whole wafers. It dominates CMOS image sensors and is being studied for memory stacking. But it requires dies that match exactly in size and are mirror images of each other. Yield is also a problem: unless the good and bad dies on both wafers line up perfectly, which is very unlikely, some good dies end up bonded to bad ones and are lost. Chip-to-wafer bonding lets Intel "dictate the terms" by cutting and testing dies first and bonding only known-good dies to known-good positions. Osborn expects Intel to use both, depending on the customer and architecture, but said chip-to-wafer makes a lot of sense for logic-to-logic stacking.

On how far connection density can scale, Osborn gave numbers. About 15 years ago, first-level interconnect pitch was 130–150 micrometers. Intel's Foveros does 25 micrometers in high-volume manufacturing today, and his lab works below 10. A paper at this year's IEEE ECTC conference reported reliability data at a 0.45-micron pitch, another order of magnitude in density. Osborn sees "a long runway." The upper wiring layers inside a die are around 0.5–1 micron, so at packaging pitches of 0.5 micron or below, one could imagine removing top layers and bonding lower wiring layers of two dies directly. Someday that might mean thinner interconnect stacks on both sides and less total IR drop between the two transistor layers.

Asked about uses beyond AI, Osborn said companies are exploring hybrid bonding for client devices too. One reason is raw density, for example between a CPU and GPU. Another is power: finer interconnects reduce energy per bit (picojoules per bit) at the interface, which lowers the system power budget and heat for the same electrical performance.

48:08

The tool bottleneck: 2X, not 10X

The second half of the episode turns from better chips to more chips. Patel spoke with Pushkar Ranade, Intel's CTO, noting that ASML makes fewer than 100 EUV tools a year, does not plan to make significantly more by the end of the decade, and must split them among Intel, TSMC, and memory makers such as SK Hynix.

Ranade agreed this is a limiter, but said ASML is not the only one. "To a large extent, we're seeing all equipment seeing tremendous supply shortage." Even where multiple vendors make a type of tool, once a process like 18A is defined it requires a specific tool from a specific supplier, and Intel cannot substitute another. To keep flexibility, Intel and the industry try to maximize tool reuse between nodes. Ranade estimated that perhaps 80% of the 18A tool set can be reused for 14A, with some new tools needed for the denser geometry.

Asked what limits output from a fixed set of tools, Ranade said gains are incremental. Yields are already high, and each additional 1% is very hard to get from a finely tuned process. Then Patel asked whether there are enough tools in the world to produce 10 times as many leading-edge wafers. Ranade answered: "Not 10X, but probably 2X, yes." Patel pointed out that AI compute has grown about 3X a year for a decade. Ranade said output cannot increase unless the whole supply chain, from equipment makers down through their suppliers and sub-suppliers, produces more.

Patel offered his own rough calculation: a couple billion dollars of Intel CapEx could yield logic for enough chips to support about $100 billion a year of AI model revenue, though many other players and memory are also involved. He suggested AI labs might eventually tell foundries to produce everything they can and guarantee future revenue. Ranade said there are "early signs" this may already be happening. He described the industry moving from full vertical integration 30–40 years ago to a horizontal structure, and now toward something "virtually vertically integrated." Hyperscalers design their own chips, and some model companies could consume one or more fabs' worth of silicon on their own and have the capital to pay for it.

53:29

Economies of scale and catching up to TSMC

Patel noted that TSMC ships upwards of 3X as many leading-edge wafers as Intel and asked how much scale matters. Ranade said scale economics in foundries are "probably the purest" of any advanced manufacturing business, because once a fab is built, about 80% of its cost is fixed. Every additional point of utilization or output matters a great deal. Raising die yield from 60% to 65% or 70%, he said, gives a better-than-linear gain in output from the same footprint. He attributed industry consolidation to this. He recalled a chart showing around 20 foundries 40 years ago and only three at the advanced node today.

Asked for the plan to catch up, especially while TSMC's N3 is reportedly mostly AI accelerators and demand for CPUs is also surging, Ranade separated scale from technology. Scale will be a gradual catch-up, since TSMC is much larger than Intel and Samsung. On technology, "I think we're already there," perhaps a few percent off on performance, power, or density. Those comparisons matter when one is a full generation or two apart, he argued, but within a few percent "you're splitting hairs." What matters more is being on time and having high enough yields to support large, fast ramps. When Patel cited SemiAnalysis estimates that 14A, due in 2028, would match TSMC's N2 in transistor density, Ranade replied, "I would dispute your benchmarking." He added that a node contains several transistor types (low-leakage, high-drive-current), several SRAM variants, and analog and RF circuits, and competitiveness depends on all of them together.

Patel compared TSMC's roughly $50 billion of CapEx this year with Intel's roughly $20 billion, and argued that tools bought now will decide who can serve future AI demand. Ranade called the comparison "a little bit unfair," because TSMC is a foundry for almost everyone while Intel is still mostly a foundry for itself. He said Intel's CapEx will grow as it takes on outside customers.

Patel also raised Intel's past exits from DRAM and, a few years ago, from flash, both now enormous businesses because of AI. Ranade conceded that in hindsight it was "probably not the smartest time to sell off a flash memory business," while saying there were good reasons then and nobody foresaw this demand. He added that he thinks the supply crunch is now larger for memory than for compute.

Patel summarized his reading of Ranade's view: marginal production can rise quickly, within about 12 months, but total growth through the end of the decade is very limited. Ranade agreed, with the caveat that the whole supply chain would have to ramp. It is already mid-2026, he noted. An enormous tool order placed today would take about 18 months to arrive, landing in roughly 2028, and building a new fab shell pushes things to about the end of the decade.

1:01:08

Terafab, and rethinking the fab from scratch

Patel asked about Intel's partnership with Elon Musk on "Terafab." Ranade said Musk had publicly expressed a desire to build a fab, driven by expected silicon needs for compute and memory across Musk's businesses, and had considered doing it alone. Because chipmaking is far more intricate than, for example, building cars, Intel thought working together could speed up the effort. Patel pushed back: if tools are the bottleneck, a new fab doesn't add silicon to the world, it only gives its owner guaranteed supply. Ranade said fabs also need power, water, consumables, and clean room space. Patel suggested those can scale in ways tools cannot. Ranade agreed that some can, more than others, and said the world needs both more equipment and more raw clean room capacity.

On fab economics, Ranade said that by his estimate fab construction costs have doubled every four to five years over decades, and lithography, the most expensive module, has risen even faster. A High-NA EUV scanner and its associated equipment cost about $400 million today. Extrapolating that trend would imply $800 million for patterning four years from now, which "doesn't really make sense." That leads him to ask what could be done radically differently now. The industry is deeply risk-averse "for very good reason," because tens of billions of dollars are at stake. But decades of repetition produce a kind of indoctrination, where new engineers are taught the process flow and "take that as gospel."

Asked what he had in mind, Ranade said "all of the above." Transistor architecture will keep evolving along a well-defined roadmap, but he also questioned the infrastructure itself: "Do you really need a clean room today?" Patel proposed an experiment with people eating hamburgers and smoking cigars in a research fab to see what happens to yield. Ranade called it a great experiment that no incumbent, whether Intel, TSMC, or Samsung, would willingly run, because every lost day of productivity is so costly. Fear of the unknown keeps the potential savings from skipping clean rooms off the table, which is why he thinks it is sometimes good to "start with a clean slate." He said the same applies to chip design, where many CPU design methods were "probably locked in 30 years ago," though he sees more room for risk-taking in design than in manufacturing.

Patel closed with a recommendation. If Intel already has fabs and room to expand, and the eventual bottleneck is upstream tools, it should raise as much capital as possible now and make large purchase commitments, as Nvidia reportedly has done for memory and other components. Otherwise, in a couple of years Intel might find it "could be making trillions of dollars right now, but all the tools are in Taiwan." Ranade called it "a very valid question" and gave the episode's final answer: "Had we known what we know today, we would have invested more like a year ago. Knowing what we know now, I think we'll be investing more."