Segment 2: How Are Semiconductors Made?

So, how are semiconductors made? It’s a blend of cutting-edge science and impressive industrial precision—a mix of chemistry, physics, and engineering that brings together expertise from around the world.

It all starts with silicon, one of the most abundant elements on Earth. Silicon is extracted from quartz sand and purified to an incredibly high level (99.9999% pure). The purified silicon is then melted, cooled into large cylinders called ingots, and sliced into thin discs known as wafers. Each wafer will eventually hold hundreds or even thousands of tiny chips.

Next comes one of the most intricate steps—photolithography. Imagine trying to draw an extremely complex circuit on the wafer, but at a scale so tiny that it’s measured in nanometers. This is done using ultraviolet light in a process called Extreme Ultraviolet (EUV) Lithography. Light passes through a mask, like a stencil, and projects patterns onto the wafer, creating billions of tiny transistors that act as switches. This process is so precise that each detail is smaller than a single red blood cell.

The machines that make this possible—called EUV lithography machines—are built by ASML, a company based in the Netherlands. Each machine costs around $200 million, has more than 100,000 parts, and takes years to assemble. These machines aren’t just expensive; they’re critical.

Zerodha • Who Controls the Chips, Controls the World