“Moore’s Law Is Over” – Three Predictions About the Computers of Tomorrow
Moore's law – the number of transistors in a dense integrated circuit doubles about every two years while the costs are halved.
Gordon Moore, Fairchild Semiconductor (1965)
"Moore's Law is over," says Mike Muller, chief technology officer at chip designer Arm, the Japanese-owned company whose processor cores are found inside most mobile phones.
Given Moore's Law has been the engine driving the breakneck pace at which computers have advanced over the past 50 years this statement might seem worrying.
"On one level it's true, but I'd say, certainly from my perspective and Arm's perspective, we don't care," he says.
Muller and his colleagues have good reasons for their indifference to the end of Moore's Law.
For one, the bulk of Arm-based processors are sold into the embedded computing market, where there is still plenty of scope for transistors to get smaller and chips to get faster.
But more importantly, Arm believes the regular boosts to computing performance that used to come from Moore's Law will continue and will instead stem from changes to how chips are designed.
Here are three ways that Arm expects processor design will evolve and advance.
1. 3D chips will continue to improve processor performance. Muller believes chip designers will continue to squeeze more power from processors by stacking more transistors and processor dies on top of each other.
"There's a whole bunch of stuff happening in 3D, whether that's within the silicon and 3D transistors stacking within a die, [or] stacking dies together," he said.
2. Computers will rely on increasingly specialized chips. Today's systems offload workloads to processors tailored to accelerate tasks. For example, offloading 3D rendering to GPUs or running trained machine-learning models on Google's TPUs, Muller predicts future systems will have an even more full range of specialized chips.
Greg Yeric, director of Future Silicon Technology for Arm Research, says there's plenty of runway to continue improving accelerators.
"For the next three to five years there's a lot to be gained just by making better CMOS-based machine learning," he says.
3. Computers will move beyond silicon chips. Soon, it's possible we will reach the limits of conventional materials and technologies used to build processors, such as the CMOS (Complementary metal-oxide-semiconductor) chips used today, says Yeric.
At this point, the chips inside systems will become more diverse, with traditional CMOS chips sitting alongside more exotic forms of information processors.
"We're going to start to see accelerators that are hardware differentiated," says Yeric.
"So, you can have a special kind of transistor that does one thing really well, [which] doesn't necessarily do all [computing] well, and you can have a chip that bolts onto a regular CMOS chip.
"We have widgets that vastly outperform CMOS on certain things. It could be photonics; it could be spintronics; it could be new memory.
"Architecting those systems is going to be a bit more of a challenge. However, I really don't see that we're going to have a slowdown at the system level, it's just that the systems won't look like a big monolithic piece of CMOS."
Muller says to expect the likes of neuromorphic, spintronics, and even quantum photonic chips to find their way inside systems.
"There is going to be in the 10-15-year timeframe new technology to take us beyond CMOS," he says.
"Products, as bought by people like you and me, are just going to keep getting better and better.
"Our jobs [chip designers] might be getting harder and harder, but from a consumer's perspective there isn't going to be a slowing down," he says.