Making the Chips that Run the World

Making the Chips that Run the World A piece of cake: put 9½ million transistors in a space the size of your thumbnail and allow zero contamination

For the people who make the chips running the computer on which you read this, "bunny suits" are no mere Halloween costumes. Such head to toe white fabric suits — designed to keep contamination by humans to a minimum — are de rigueur at the Intel plant where author Jake Page discovers the intricacies of making microprocessors and other computer chips.

The diminutive engines that power our global village start as pure silicon. Melted and resolidified to form single, 250-pound crystals, the silicon is sliced into thin, eight-inch-diameter wafers. These wafers must be flat — varying no more than one-hundredth of the thickness of a human hair. As many as 100 to 600 chips are built up on each finished wafer, with some 20 layers of different materials carefully placed to form circuits, and millions of transistors, on a thumbnail-size space.

To do any of this requires one thing first and foremost: cleanliness. After all, a cubic foot of the air you are breathing right now contains a million specks that are one-fifty thousandth of an inch or larger, any of which could wreck a tiny microprocessor. In the rooms where chips and wafers are made, air is changed six times a minute.

In the 1960s, Gordon Moore, Intel's cofounder, noted that the number of transistors per chip would double every year. Decades later, in a business where smaller is better, Moore's Law still holds true.

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