The Galaxy S6 runs on a Samsung 14nm FinFET chip, the Exynos 7420, and that sentence is a small earthquake. For the first time Samsung is shipping a more advanced transistor than TSMC, whose competing parts are still on a 16nm process a half-step behind. The fast-follower just became the leader, at least on paper, and it did it exactly the way it told itself it would once Apple started drifting toward Taiwan: not by grinding out another mature node, but by being first to the new transistor.
FinFET is the biggest change to the transistor in a generation. The old planar device is a flat switch, and below a certain size it leaks current it cannot control, bleeding power as heat. The fin stands the channel up on its edge and wraps the gate around three sides of it, which claws back control and kills the leakage that planar nodes like the 20nm everyone is abandoning could no longer manage. Samsung got its fins working in volume before TSMC got theirs out the door. After years of being the second call, that is a genuine reversal.
The Exynos 7420 is the proof it is real and not a slide. It is fast and it stays cool, which carries the Galaxy S6 to the front of the market on the strength of its silicon, after a couple of years of Exynos parts that ran hot enough to embarrass the company. The turnaround is not subtle. A foundry that can be first to FinFET and yield it well enough to ship in Samsung’s own flagship is a foundry the whole fabless world has to take seriously again.
Samsung does something shrewd with the lead. It licenses the 14nm process to GlobalFoundries, so two fabs on two continents can build the identical design, doubling the capacity any customer can count on and answering the question every big customer asks before committing: what happens if your fab has a bad quarter. Qualcomm is the prize. Its current Snapdragon 810, built on TSMC’s 20nm planar, has spent the year fighting a reputation for running hot, and the next flagship is coming to Samsung 14nm instead, the kind of marquee Android win that used to go to TSMC by reflex. The GlobalFoundries license is part of what closed it.
Even Apple is back, sort of. The next iPhone chip looks like it will be dual-sourced, some built by Samsung on 14nm and some by TSMC on its 16nm, the first time Apple has split a single processor across two foundries. For Samsung, clawing back even half of the Apple business that walked to Taiwan is vindication. The risk nobody is talking about loudly yet is what happens if two fabs building the same chip do not build it quite identically, if one version runs a little cooler or lasts a little longer than the other. Perso, I suspect that worry is overblown, the designs are the same and both fabs are excellent. We will see.
For the first time since it started renting out fab space, Samsung is unambiguously ahead. It has the newest transistor, a flagship phone proving it works, a licensing deal that doubles its capacity, and a piece of the Apple account back in the building. The thing about being first, though, is that it sets a bar you then have to clear every single node, against a competitor that has made not-losing its entire culture. Samsung leapt. Whether it can keep leaping, or whether being first this once is the whole story, is the question the next few years decide, and the answer is not obviously yes.