As Joseph Jacobson is fond of pointing out, for all the gains in semiconductor chip performance over the past few decades, a typical integrated circuit-the brains behind your computer-is still far too expensive for most people on the planet. “Look at the way [a chip] is made,” he says, punching the air with one hand while directing a PowerPoint presentation with the other. Fabricating a high-quality logic chip like Intel’s Pentium processor, he points out, takes “two weeks, seven days a week, 24 hours a day. Chip fabrication facilities like the ones that Intel has are a $1.6 billion tool. And there are very few people on the globe who can touch that tool.”Jacobson’s solution: a “desktop fab” able to print circuits directly on a substrate, such as plastic, without the expense and hassle of a multibillion-dollar manufacturing facility. Jacobson, head of the Printed PC Group at MIT’s Media Lab, has already managed to print rudimentary but working transistors using an “ink” consisting of nanometer-sized semiconductor particles. “Our goal is to follow the trajectory silicon took, and start printing processors with perhaps several hundred transistors, moving to thousands and then more,” says Jacobson. “We should be able to demonstrate a very simple processor in the next 12 to 18 months.” And he predicts that printed logic chips with the speed and power of a Pentium could eventually be possible, making microchips available for a fraction of the time and expense associated with conventional manufacturing.
If Jacobson’s vision becomes reality, it could change everything in computer hardware. Printed electronics could be cheap enough to find their way into everything from “wallpaper” able to display changeable images to custom-designed logic circuitry. A chip fab on every desktop could bring about the day when individuals download the architecture of integrated circuits the way they download software today. It could, in short, transform hardware manufacturing much the way the “open-source” movement has changed how software is written. Indeed, at his most visionary, Jacobson contends printed logic could give rise to an open-source hardware movement where chips are custom-designed via the Internet and printed by the consumer in about the same time it takes to print out a Web page. You could, says Jacobson, “download the chip design from the Web, tie in some modifications from some guy in India, and boom-out comes the device.”
It’s lunchtime in Jacobson’s lab, a windowless room with tangles of colored cable dangling from the walls and ceiling and a row of chemical hoods set along one wall. Jacobson’s enthusiasm is contagious, and the cramped lab is obviously where he and his handful of students spend most of their time, even when they’re eating. “What we’re interested in is give me a piece of plastic and in a few seconds I’ll give you back a Pentium,’ or something of that complexity,” he says between mouthfuls. “I’m serious about that. Not slower than a Pentium; indistinguishable from a Pentium.”
Coming from almost anyone else, such a claim would be hard to swallow. But the 35-year-old associate professor has the credentials to deliver the goods. After all, when Jacobson joined the Media Lab in 1996, his immediate ambition sounded nearly as outlandish. “I wanted to have a display [screen] that could be printed,” Jacobson recalls. “I wanted something that was incredibly inexpensive, something that would look like ink on paper.” Something, in other words, like “electronic paper.”
His solution was a riff on research conducted at Xerox Palo Alto Research Center (PARC) in the 1970s, where researchers had created microscopic balls that were black on top, white on the bottom. An electric charge determined which side of the balls rotated upward. With some clever wiring, the balls could be made to form letters and words. Jacobson and a handful of MIT undergrads pushed the idea in new directions. Rather than making balls of two colors, they fabricated millions of tiny microcapsules, each containing a liquid mixture of oil, dark dye and tiny shards of white pigment. They then layered the material onto flexible plastic and sandwiched it between transparent electrodes on top and bottom. Depending on the charge applied, the white shards migrate toward the top or bottom of the sphere, and when activated in concert, the electrodes can force the ink into recognizable patterns.
The rest is the stuff of venture-startup legends. E Ink was formed in 1997 with several of Jacobson’s students at the helm, and has since raised nearly $55 million in private financing, forming deals with the likes of Motorola and Hearst Publishing. Media and pundits alike have proclaimed the technology as the end of paper as we know it. But what got lost in all the buzz over electronic paper is that you still need electronics to drive the pixels (the ink) of the displays. The prototypes built thus far by E Ink continue to rely on traditional (read: not cheap) silicon chips to control the display. To reap the full benefits of the technology, you need cheap, flexible electronic circuitry. E Ink has recently partnered with Lucent Technologies, whose researchers have been working on ways to print organic transistors onto flexible plastic substrates. (The two companies hope to unveil a working prototype of the technology this fall.)
Jacobson, however, has even larger ambitions. Not only does he want to print the relatively simple electronic circuitry required to control a display screen, he wants to go the next step and find a way to fabricate high-quality logic on the order of a Pentium using similar printing methods. Not only would you be able to “print” your screen; you could, in a sense, print the PC itself-or at least its essential circuitry.