Making microprocessors demands that the people who make them are as clean as the environment in which they work. This is because a microprocessor-itself about the size of a dime-contains millions of microscopic transistors. The tiniest speck of dust to a chip would be like a Godzilla-sized footprint to us, and it could ruin thousands of transistors.

	This enlarged image of a grain of salt on a piece of a microprocessor should give you an idea of how small and complex a microprocessor really is.

How Clean Is Clean?
The ultra-clean environment where microprocessors are made is called a cleanroom. "Class One" cleanrooms are the cleanest of all, with no more than one speck of dust per cubic foot.

How Small Is Small?
Imagine a boulder large enough to cause traffic jams all over a big city. If one fell on Times Square in New York, it could stop traffic on many streets around it, and eventually stop traffic on adjacent streets through a ripple effect. The same is true of a speck of dust landing in the middle of a microprocessor. Just one microscopic particle can obstruct the chip's pathways, ultimately rendering it unusable.