Comment by Sysreq2 | Hacker News Reader

Comment by Sysreq2 | Hacker News Reader

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The nomenclature for microchip manufacturing left reality a couple generations ago. Intel’s 14A process is not a true 14A half-pitch. It’s kind of like how they started naming CPUs off “performance equivalents” instead of using raw clock speed. And this isn’t just Intel. TSMC, Samsung, everyone is doing half-pitch equivalent naming now a days.

This is the industry roadmap from 2022: https://irds.ieee.org/images/files/pdf/2022/2022IRDS_Litho.p... If you look at page 6 there is a nice table that kind of explains it.

Certain feature sizes have hit a point of diminishing returns, so they are finding new ways to increase performance. Each generation is better than the last but we have moved beyond simple shrinkage.

Comparing Intel’s 14A label to TSMCs 16A is meaningless without performance benchmarks. They are both just marketing terms. Like the Intel/AMD CPU wars. You can’t say one is better because the label says it’s faster. There’s so much other stuff to consider.

> This is the industry roadmap from 2022: https://irds.ieee.org/images/files/pdf/2022/2022IRDS_Litho.p...

Very interesting document - lots of numbers in there for real feature sizes that I had not seen before (Table LITH-1).

And this snippet was particularly striking:

Chip making in Taiwan already uses as much as 10% of the island’s electricity.

"Likely better" doesn't come from 14A vs 16A. It comes from Intel using High NA-EUV vs TSMC using double pattern Low NA-EUV.

If Intel pulls off DSA, they will be using a newer generation of technology compared to TSMC using an optimized older generation. Could TSMC still make better chips? Maybe. But Intel will likely be better.

> If Intel pulls off DSA, they will be using a newer generation of technology compared to TSMC using an optimized older generation. Could TSMC still make better chips? Maybe. But Intel will likely be better.

Is Intel working on "an optimized older generation" as a backup plan? I don't follow semiconductors very closely, but my impression is the reason they're "behind" is they bet aggressively on an advanced technology that didn't pan out.

From what I remember the aprocyphal story is that Intel dragged their feet on adopting EUV and instead tried to push multi-patterning past it's reasonable limits.

If that's the actual root cause, then Intel's lagging is due to optimizing their balance sheets (investors like low capital expenditures) at the expense of their technology dominance.

I am not sure where that would come from. There is nothing about dsa that means this.

Dsa is one of many patterning assist technologies, just...an old one. Neat, but not 'new'. You use patterning assist to make smaller, more regular features, which is exactly what the 16a vs 18a refers to.

That has somewhat less to do with performance, which is tied as much to material, stress, and interface parameters. Nothing gets better from being smaller in the post dennard scaling era, the work of integration is making better devices anyway.

Patterning choices imply different consequences. For example,.a.double euv integration can take advantage of spacer assists to reduce ler and actually improve cdu even with a double expose. Selective etch can improve bias, spacer trickery can create uniquely small regular features that cannot be done with single patterns. Conversely, overlay trees get bushier, and via CD variance can cause horrific electrical variance. It is complicated, history dependent, and everything is on the developmental edge.

DSA is what is going to make it possible for Intel to compete at all. Without it, they are going to have fancy machines in fancy foundries that are too expensive to attract any customers.

To the best of my knowledge, DSA never made it out of the lab.

But still, what is stopping others from also developing DSA? I am not sure the technology alone will be Intel's savior. They've been on the decline for a while, ever since they took a jab at Nvidia for releasing CUDA, they demonstrated a narrow vision, consistently, and now they're playing a catch up game.

> Intel’s 14A process is not a true 14A half-pitch. It’s kind of like how they started naming CPUs off “performance equivalents” instead of using raw clock speed.

Earlier it was AMD. The most prominent era since their Athlon XP CPUs turned out to be noticeably more performant per GHz than Intel in 2001.

would performance per watt be the right way to benchmark?

Benchmarks are tricky because it all depends on workload and use case. If you are in a VR headset for example, it’s all about power envelope and GPU flops. If you are in a Desktop used for productivity it might be all about peak CPU performance.

When comparing fab processes, you wouldn't want performance of a whole processor but rather the voltage vs frequency curves for the different transistor libraries offered by each fab process.

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