How are microchips made? - George Zaidan and Sajan Saini

This is a computer chip, magnified 500 times.

What you’re looking at is the top of a computing city, with distinct neighborhoods for different functions.

They’re linked by up to 100 kilometers of ultra-thin copper lines, running across 10 or more stacked levels.

At the very bottom, billions of electronic devices generate the digital traffic that pulses across the chip.

The most common of these devices is called a transistor; it’s a switch that allows current to flow if it receives a voltage.

Transistors can be as small as 20 nanometers, and more than 50 billion of them can fit on a single chip.

Globally, we produce more than a trillion computer chips every year.

That’s about 20 trillion transistors built every second, and it’s done in fewer than 500 fabrication plants, known as fabs.

How do we build so many tiny, intricately-connected devices, so incredibly fast?