Saving Moore's Law

We've known for several years now that Moore's Law, which states that transistor density in integrated circuits doubles approximately every two years, was running out of time. But why is that the case?

The simplest way to explain the myriad reasons why transistors aren't scaling as they used to is this: We have hit the limits of perfection. We need perfect feature sizes at sizes so tiny, we can't build a laser small enough to etch them. We need to control the level of dopants (deliberate impurities in the silicon substrate) to within 10s of atoms. Heisenberg himself is tugging at the sleeve of Intel's finest engineers and clucking disapprovingly.

What to do? Quantum computers are decades away from marketable products, if it's even possible to make them into home appliances. But we can't just squat here; we absolutely must have faster computers every two years, otherwise the Earth will explode or something. Luckily, some whitecoats have found a solution: vacuum tubes.

Seriously. Itsy-bitsy, teeny-weeny, vacuum tubes.

Earth explosion is called off until the next crisis. Go read.