Exactly how much data can fit on the head of a pin? Chipmakers still aren't sure. At a conference in late February, engineers from NEC, Toshiba, and Hitachi showed off designs of new memory chips that can store 256 million bits of data, 16 times as many as today's most advanced DRAMs, or dynamic random-access memories. The companies expect to turn out these new chips, which will hold about 11,000 pages of text, in six years.
Though the designs would seem impossible to make, Jim Handy, a senior analyst at Dataquest Inc., notes that engineers have been wrongly predicting a manufacturing brick wall for years. "Every time they run into one, they find a way around it," he says. One possibility this time is to stack transistors atop one another. Another is using a new technique, called phase-shift masks, to create thinner circuit lines--of just 0.25 micron, or / the thickness of a human hair, a big gain over the 0.6-micron lines in today's 16-megabit chips.