Photolithography is a manufacturing technique that allows chip manufacturers to create astoundingly small circuit elements: the microscopic transistors, capacitors, interconnects, and so forth that an IC needs for proper electrical functionality. This is its primary role in IC fabrication. Its secondary role—only slightly less important—is drawing smurfs, sailboats, dinosaurs, medieval weaponry, and the numerous other decorations concealed rather mysteriously within these otherwise utilitarian electronic components.
It is only fitting that Dilbert should be included in silicon-art portraiture. Photo courtesy of the Molecular Expressions “Silicon Zoo” gallery maintained by Florida State University. Used with permission.
The Origin of Silicon Art
The existence of these diminutive artworks is not in question. Michael Davidson at Florida State University has documented a pleasantly bewildering assortment of people, animals, objects, and symbols etched into microchip silicon. You can see the photographs and read the interesting commentary on Molecular Expressions.
The issue, then, is why they exist. Semiconductor design and fabrication is an expensive and immensely complex process, involving prodigious technological sophistication and requiring the expertise of eminent scientists, engineers, and technicians. What is the motivation behind these artistic flourishes? Did management actually approve the addition of frivolous imagery to IC layouts?
The Omnipresent Urge for Personal Expression
The first explanation applies as much to silicon art, also known as chip art or chip graffiti, as it does to artistic intrusions into other industries and professions. Human beings have a natural desire to personalize their handiwork, identify with their creative achievements, and imbue utilitarian objects with cultural significance. Seen from this perspective, silicon art is not fundamentally different from ancient Athenian vase paintings or the elaborately carved wooden gates that I saw every day when I lived in eastern Europe.
Still, there is something surprising and intriguing about an engineer’s urge to “sign” his or her integrated circuit with initials, a cultural symbol, an inside joke, or some other vehicle for personal expression. First, these drawings are not only concealed but also invisible to the naked eye. To appreciate silicon art, you need to break open the IC and use a powerful microscope.
Second, integrated circuits represent the triumphant culmination of the “technological virtues”: interdisciplinary collaboration, mathematical precision, scientific rigor, painstaking analysis, closed-loop reasoning. It’s hard to shake the feeling of dissonance that surfaces when you see the face of Daffy Duck etched into the surface of a microprocessor.
Daffy isn’t the only cartoon character that was honored with a chip-art rendition. Photo courtesy of the Molecular Expressions “Silicon Zoo” gallery maintained by Florida State University. Used with permission.
In the earlier years of IC production, semiconductor companies used silicon art as a means of protecting intellectual property. IC layouts were not automatically copyrighted, and a competing design team could examine an integrated circuit, duplicate the layout, and fabricate its own “version” of the chip. If a subsequently produced die contained an undeniably nonfunctional portion of an original die’s layout, such as a drawing of the lunar lander, it was safe to assume that the new “version” of the IC was a flagrant copy rather than the result of reverse engineering.
My intuition tells me that companies did not frequently employ silicon art as an official IP-protection technique. I could be wrong. In any case, the technique became unnecessary in 1984, when the Semiconductor Chip Protection Act ensured that an identical IC layout would be automatically deemed copyright infringement.
Orbiting Texas Instruments’ Schottky digital bipolar logic ICs was this etching of a space shuttle. Photo courtesy of the Molecular Expressions “Silicon Zoo” gallery maintained by Florida State University. Used with permission.
The End of an Era
The seventies and eighties were the golden age of silicon art. A period of decline followed, and it seems unlikely that investigators of the future will discover superfluous doodles and witticisms hidden in the ICs of the twenty-first century.
The difference between the semiconductor industry of the seventies and the semiconductor industry today is perhaps analogous to the difference between a family-owned carpentry shop and a furniture factory. Engineers of the golden age worked in smaller teams, with less specialization and software to psychologically distance them from the ICs that they designed (and perhaps also tested or characterized). The result was a natural desire to personalize their creations and express their sense of creative ownership.
As the industry matured in the late eighties and nineties, semiconductor production became more standardized and automated, and the economic stakes were higher. Individual IC designers didn’t strongly identify with the final product, and a shift occurred in the working environment. Chip designer Dan Zuras explained that “as chip projects got larger, more bureaucratic, and driven and controlled by software, the managers became more separated from the designers. They became afraid of [silicon art], because it might break something.”
These Martians were actually on Mars—the drawings were etched into an image sensor used in the Spirit and Opportunity rovers. Photo courtesy of the Molecular Expressions “Silicon Zoo” gallery maintained by Florida State University. Used with permission.
The Uncertain Future of the World’s Smallest Art
It’s discouraging to think that there’s no longer room in the semiconductor industry for silicon art. The corporate culture has changed, the workflow has changed, the tools have changed, and I think that in some ways, engineers have changed.
Maybe it’s a positive shift. Maybe engineers have found better—more individualized, more sensuous, less clandestine—ways to cultivate the imagination, express whimsicality, or explore aesthetic sensibilities.
Nonetheless, it’s hard not to lament the loss of an art form that juxtaposes rudimentary—sometimes almost petroglyphic—line drawings with the most advanced technology on the planet.