St. Louis — By the end of the decade, robots may be replacing workers in the manufacture of computer chips because people are, well, just too dirty. The problem is that, as computer chip manufacturers stuff more electronic components into the same-size area, the control of such factors as dust becomes critical.
''A human hair is about 75 microns wide. The active elements in today's circuits are a half-micron in size. The process of miniaturization has gone so far that it is very difficult, even for us in the industry, to comprehend,'' explains Don L. Tolliver, who works for Motorola's semiconductor division in Phoenix.
To achieve this degree of miniaturization, computer-chip makers must use silicon, which is incredibly pure. ''You're looking at the most perfect thing you'll ever see,'' says Dieter K. Schroder of Arizona State University, holding up an ingot of silicon.
At these sizes, even tiny motes of dust can gum up the works. And in a room filled with people, there are typically 100,000 micron-sized dust particles every cubic foot.
As a result, current semiconductor plants typically spend $5,000-10,000 a month on electricity just for air purification and conditioning. Even so, impurities force manufacturers to discard 30 to 50 percent of all the chips they make.
Computer memory chips, called dynamic random access memory or RAM, are particularly susceptible. Manufacturers are now packing at most 256,000 bits, or information units, on a chip. But all are working furiously on packing a million bits into single RAM chips.
''When we're hit by the megabit chip, people will be going crazy, trying to control impurities,'' Tolliver predicts.
Although robots are extremely expensive, the demand for ultracleanliness may ban human beings from the chip factory floor.
After all, ''robots don't smoke or wear cosmetics,'' jibes George A. Rozgonyi , a microscopist at North Carolina State University.