Essential Guide to Semiconductors, The

Silicon Ingots to Start

The first step in making any silicon chip is getting the silicon, of course. Silicon is basically purified sand; it's one of nature's elements and, thankfully, one of the cheapest and most plentiful. For the chemists in the audience, silicon is element 14, right between aluminum and phosphorus on the periodic table of elements. For the nonchemists in the audience, silicon is not the same as silicone, the stuff that lubricates squeaky door hinges or maintains the business of cosmetic surgeons.

Silicon crystals are melted in a vat and purified to 99.9999 percent purity and grown into ingots, long sausage-like cylinders that are heavy and shiny, as shown in Figure 4.2. If you've ever grown sugar or salt crystals in a drinking ...