Brilliant! Shuji Nakamura and the Revolution in Lighting Technology

 Bob Johnstone
  21st-Mar-2007
I N T R O D U C T I O N The eminent historian of technology Tom Hughes employs a military metaphor to describe problems that remain to be solved as technological systems expand. He calls them “reverse salients”. Innovation advances across a broad front, leaving reverse salients sticking out behind. These pesky pockets of resistance often defy efforts to mop them up. They bring progress elsewhere grinding to a halt. For obvious reasons, reverse salients attract ambitious inventors. A classic case of a reverse salient is the bright blue light emitting diode. LEDs - tiny specks of semiconductor material that shine when hooked up to a voltage - were invented in 1962. Thirty years on, researchers had made considerable progress in refining the technology. From its humble origins as a dull red on/off indicator, the LED had evolved to become, among other things, the bright red brake lights on cars. Along the way, other colors had also emerged: amber, yellow, and yellow-green. But the light emitting diode was still a long way from fulfilling the destiny that the device’s pioneers had predicted for it. That is, to replace every other form of lighting, including Edison’s light bulb and the fluorescent tube, in our homes, offices, and everywhere else besides. Such a large-scale replacement would be a very big deal, for all sorts of reasons. First and foremost, in terms of reduced energy consumption. Symbol of innovation though it may be, the incandescent light bulb is in fact a throwback to the nineteenth century. Edison’s best-known invention is a gross object made from gas, glass, and brass. Suspended within the glass is a flimsy, very Victorian-looking metal contraption called a filament. Light bulbs guzzle energy, wasting nintey-five percent of their output in the form of infrared heat. And, as we all know from bitter experience, light bulbs are irritatingly prone - plink! - to burn out after only a few months. One in three bulbs needs to be replaced every year. Light emitting diodes, by contrast, are solid-state devices made up of layers of semiconductor material just a few atoms thick. They are arguably the world’s first ubiquitous nanotechnology. LEDs are cool, literally - touch one and see - and metaphorically, too, in terms of what you can do with them. They consume eighty percent less energy than incandescents. They are mechanically robust, almost unbreakable. They last for up to a hundred thousand hours, over a decade, effectively forever (because you don’t leave lights turned on all the time). And like old soldiers, LEDs do not die, they gracefully fade away. Since lighting accounts for around a quarter of electricity usage, replacing conventional lights with LEDs would dramatically cut our energy consumption. In the US, by far the world’s largest user of electricity, energy consumption would decline by almost thirty percent. Through switching to solid-state lighting consumers might expect to save $125 billion dollars over the next 20 years. That does not include many more billions of dollars in construction costs that could be avoided as a result of not having to build new power plants. (In the US alone, 135 new coal-fired plants are currently on the drawing board.) Fewer fossil-fuel electric plants would mean a reduction in carbon emissions of hundreds of millions of tons. In addition to which, LEDs are themselves intrinsically environment-friendly. They contain no toxic substances like mercury, which is used in fluorescent tubes, thus do not threaten landfills, groundwater, and ultimately, our health. Light emitting diodes would generate economic growth, giving birth to a whole new industry. The products of this industry would do far more than just replace existing lights. As Herbert Kroemer - the Nobel laureate from whose fundamental insights modern LEDs derive their efficiency in converting electricity into light - instructs, a breakthrough technology creates its own applications. Witness the transistor, the most significant application of which was not as a replacement for tubes in radios and TVs, but as the sine qua non of the personal computer, an application that no-one imagined initially. LEDs, like transistors, are semiconductors. Their performance keeps going up even as their price keeps coming down. Haitz’s Law, the LED equivalent of Moore’s Law, states that each decade since the first LED appeared device performance - in this case, the amount of light they output - has increased by twenty times, while device price has fallen by ten times. Solid-state lighting couples naturally with digital devices like microprocessors to integrate LEDs into a host of innovative applications. For example, you might be able to adjust the color of the lighting in your living room to suit the occasion, the time of day, or your mood. (Northern Lights? Sunset in Maui? Not a problem.) This ability to do new and previously impossible things may trigger the mass adoption of novel household lighting systems. The monster market will not be fancy tricks, however, but plain old illumination. That is, replacing incandescents, halogens, and ultimately fluorescents as the lighting technology of choice in every single socket in the world. For many people, the “killer app” of solid-state lighting may simply be tens of dollars off the monthly electricity bill. For LEDs to fulfil their destiny, however, for this unprecedented paradigm shift to occur, one last breakthrough remained to be made. In order to produce useful white light, you need - or so people thought in the early nineties - all three primary colors: not just bright red, but also bright blue and bright green. Over three decades, elite scientists at some of the world’s top universities and corporate research centers strove to solve this problem. Despite all their efforts, no-one was able to devise a solution that would rectify the reverse salient, thus enable technological progress toward solid-state lighting to resume. You could do blue LEDs, it was true, but they were very far from being bright, and seemed destined to remain so. Then, on 29 November 1993, came an announcement that astonished the world (or at least, that part of the world that knew enough to be astonished). A chink in Nature’s armor had been found! A bright blue light emitting diode had been invented! The day of lone inventors like Edison was supposedly long gone. (It took three men to create the transistor.) Now here was proof to the contrary. The finder of the chink in Nature’s armor was an individual inventor named Shuji Nakamura. His little lamp was about a hundred times brighter than previous blue LEDs. It was, quite literally, brilliant. The reverse salient of solid-state lighting was history. Initial reaction to news of the discovery of the bright blue LED was one of disbelief. Who was this unknown inventor, this presumptuous upstart without so much as a PhD to his name, this latter-day alchemist who claimed to have turned base metal into light emitting gold? Shuji Nakamura, it turned out, was a humble 36-year-old Japanese electrical engineer. He had been working by himself, in almost total isolation, personal, professional, and geographical. The company which employed him was called Nichia Chemical Industries. It was a small, utterly obscure outfit based on the island of Shikoku, way down in the boondocks of rural Japan. In American terms, it was as if the announcement had come from hillbilly Appalachia. Since then, having been held back for so long, LED technology has exploded into all sorts of applications. In less than fifteen years Nichia’s tiny lights - along with similar devices made by rival firms - have become ubiquitous. Today, you carry them in your pocket, lighting the keypad of your cellphone, backlighting its display, and providing the flash for its camera. They are on your desktop, in your computer, its screen, mouse, and flash drive. They are in the jewelry store, illuminating the display cabinets. They are on the roadside, in the form of pointillist traffic signals and vast, full-color electronic billboards. Tomorrow, Nakamura-style high brightness LEDs will find such applications as headlights in cars, shelf lights in supermarkets, reading lights (and every other kind of lights) in airplanes, and, most importantly, in our homes. The efficiency with which LEDs convert electricity into light, already high, continues to increase. Soon it will reach that of fluorescent tubes. The main problem now is cost, and cost has never stood in the way of semiconductors. As they come pounding down the experience curve, semiconductors are like a steamroller, flattening all obstacles in their path. The solid-state lighting revolution is happening now, faster than anyone imagined. Lighting industry stalwarts who used to say, “It shows promise — but not in my lifetime”, or, “Let’s wait until it reaches the crossover point,” are now frantically scrambling to climb aboard the LED bus. Light emitting diodes are already the lighting technology of choice in some high-end California houses. By 2010, as the performance of the devices continues to improve, and their prices to plummet, LEDs will be replacing incandescent light bulbs in homes across the US and fluorescent tubes in offices and commercial spaces. By 2020, the tiny lights will likely have superceded all conventional forms of illumination, with the possible exception of searchlights. * It behoves scientists to be modest about their discoveries. “If I have seen further”, Isaac Newton said, “it is by standing on the shoulders of giants.” As Shuji Nakamura himself is the first to admit, his initial bright blue breakthrough, though based on his own innovations and a decade’s worth of blood, sweat, and tears, was built on the work of others. But then, from his platform atop others’ shoulders, Shuji took off. It was as if he had rockets in his feet like Mighty Atom, his boyhood comic-book superhero. Over the next six years, from 1993 to 1999, Nakamura notched one key breakthrough after another. Following bright blue LEDs came bright emerald green LEDs (thus completing the trinity of primary colors), blue-violet lasers (thus enabling next-generation, high-definition digital video disc players), and ever brighter blue LEDs (thus producing, by adding a yellow phosphor, a simpler, hence cheaper, white light than the combination of red-blue-green). And all of these inventions were undeniable, you could actually see them with your own eyes. At international conference after international conference Shuji the Showman would blind audiences by shining his latest little lights in their faces. Cheekily, he would use his world’s-first blue laser as a pointer in his presentations. Such antics infuriated his rivals, because Shuji would always be always at least one step ahead of them. Some accused Nakamura of being an egomaniac. In fact, he was just being a great salesman, a la Steve Jobs, advertising his company’s products. Nakamura appeared - to use an entirely appropriate expression - from out of the blue. “Nobody had ever met him, had ever heard of the guy,” marvelled Gerald Stringfellow, formerly of Hewlett Packard, now a distinguished professor of materials science and engineering at the University of Utah, and co-author of a book on LEDs. “Then suddenly, he came out of nowhere, and just one thing after another fell in front of him ... . And I have been absolutely flabbergasted that one person could make such a big contribution, could be such a leader for such a long time.” “Never during the time that I am aware of,” said Fernando Ponce, formerly a researcher at Xerox PARC and now a professor of physics at Arizona State University, “have we seen somebody maintain such a huge lead, and the rest of the world not being able to compete with him. ... It’s a wonderful demonstration of what a brilliant engineer can do.” Not even a US government-sponsored consortium of US companies - including Xerox and Hewlett Packard - that was thrown together in a misguided attempt to replicate the supposed Japanese cooperative style of technology development could catch him. “Nakamura put together a string of achievements,” wrote Glenn Zorpette in Scientific American, “that for genius and sheer improbability is as impressive as any other accomplishment in the history of semiconductor research. [My emphasis.] And it is all documented in a trail of literature that is almost as stunning. Between 1991 and 1999 he authored or co-authored 146 technical papers, six books and 10 book chapters.” Nakamura’s breakthroughs laid the foundations for a whole new industry that today employs tens of thousands in Japan, North America, Germany, Taiwan, South Korea, China, and elsewhere. Participants include a few big names, plus a host of brash, entrepreneur-driven startups. Along the way Shuji has garnered most of the honors and awards going, both at home and abroad. In 2002 alone, they included Japan’s prestigious Takeda Award, and the Franklin Institute’s Medal in Engineering. Named for Ben, the Franklin awards are widely regarded as the American Nobels. A prediction by Thomson Scientific based on a citation count of his work puts Nakamura on the short list for the Nobel Physics Prize. The middle-of-the-night phone call from Stockholm may not come this year, or next, but as Shuji’s tiny electronic progeny conquer ever-larger markets with an ever-greater effect on our lives and the environment there can be little doubt that, sooner or later, it will come. To win a Nobel Prize, according to Nobel Museum director Svante Linqvist, you do not have to be a genius: what you need most of all is courage. In order to come up with his breakthrough Shuji had to defy the conventional wisdom of his peers and ignore the explicit instructions of his boss. He does not lack guts. * In 1998, after five years of setting the pace, in a plenary talk he gave in Strasbourg, France, Shuji announced that LED research was over. An exaggeration, as we shall see, but one with a kernel of truth. Most of the big breakthroughs had been made, many of them by Shuji and his group at Nichia. But the Nakamura saga was by no means over. Indeed, its most dramatic episodes were about to begin. In January 2000 came the sensational news that Shuji had done the unthinkable. He had left Nichia, the company where he had worked for twenty years, and his beloved native Shikoku - something he had vowed he would never do - to come to the US and take up a chair as a professor at the University of California at Santa Barbara. In Japan, still very much the land of lifelong employment, it was a shocking thing to do. At first, the parting of the ways seemed amicable. Shuji had gone as far as he could go with the technology; now he was leaving to pursue a more scientific vocation. In fact, as the truth of the matter emerged, the split was anything but friendly. In December 2000, Nichia sued Nakamura, accusing him of leaking trade secrets to Cree, a rival US firm. Shuji counter-sued, claiming that his old employer had not rewarded him commensurately for his efforts in laying the foundations for what had by then for Nichia become a business worth well over a billion dollars. It subsequently emerged that while Nichia’s founder had supported Nakamura’s bold challenge to develop a bright blue LED, his successor as president had done everything in his power to sideline his company’s most valuable human resource. In an act of breathtaking ingratitude, he succeeded in chasing away the goose that had laid the golden eggs. The court battles dragged on for years. In the interim, via public lectures and op-ed pieces in Japanese newspapers and magazines, Shuji became a vocal critic of the Japanese education, employment, and legal systems. Eventually, the case culminated in victory not only for Shuji, but also for the rights of the creative individual in a corporate context. Never again would a Japanese corporation be able to take for granted the efforts of its most innovative employees. Nakamura emerged from this epic legal struggle as a folk hero among the downtrodden salarymen of his native land. * The semiconductor material enabling the revolution in lighting is a compound called gallium nitride. Some experts claim that gallium nitride is the most important new material since silicon. When Shuji announced his breakthrough back in 1993, you could have fitted all the researchers working on gallium nitride into a minibus. Twelve years later, a survey listed no fewer than 626 companies, universities, and research institutes worldwide actively involved with gallium nitride, of which 232 were companies. Not all gallium nitride researchers are working on light emission, however. Shuji’s breakthrough has also cracked open another potentially huge new set of markets. Umesh Mishra, Nakamura’s colleague at UC Santa Barbara, predicts that gallium nitride devices will also have a disruptive effect in the area of power management and power supplies. Such devices will improve the energy efficiency of delivering power, just like solid-state lighting improves the energy efficiency of delivering illumination. There will also be applications for gallium nitride in broadband wireless networks, mobile computing, and hybrid vehicles — anywhere in short where you have to convert electricity from one kind to another, from AC to DC, or from one voltage to another. For example, in transformers, the ugly ‘bricks on the wall’ that terminate the power cords of so many appliances. Such things are pervasive in our existence, and they can keep getting smaller, lighter, and more energy efficient. Mishra believes that a huge second wave of gallium nitride mania is on its way. * Shuji Nakamura’s invention of the bright blue light emitting diode and the explosion of entrepreneurial activity that has ensued is more than just a tale of derring-do in the semiconductor industry. The story also contains important lessons for society on how to foster and reward innovation, hence build new industry and create wealth. Not, of course, that it would be possible to replicate the highly contingent circumstances that led to Nakamura making his breakthrough. Nonetheless, Shuji’s success basically boils down to two things. One, a talented, highly motivated researcher is given free rein by, two, a chief executive willing to gamble big on his abilites. Though Nakamura had to overcome more than his fair share of obstacles, he never had to contend with the risk-averse bureaucracy that stifles creativity at so many big corporations. “What I have managed to achieve”, Nakamura has written, “shows that anybody with relatively little experience in a field, with no big money and no collaborations with universities or other companies, can achieve considerable research success alone when he tries a new research area without being obsessed by conventional ideas and wisdom.” Though Nakamura’s breakthroughs took place at a small Japanese company, and his research flourishes today at an entrepreneur-friendly American university, neither Japan nor the US have much reason to feel complacent about these successes. • Americans should ask themselves why their federal government has done so little to promote the crucial energy-saving technology of LEDs. This is in stark contrast to other nations, especially Asian countries, China in particular, which have identified solid-state lighting as a national priority and are supporting it accordingly. Also why, despite being the source of much of the advanced technology that is driving the solid-state lighting revolution, the US has been so slow to adopt that technology. Compared to their European counterparts, US lighting companies seem reluctant to embrace LEDs and progress has been, at best, gradual. In addition, America’s much-vaunted venture capitalists do not emerge from this story well. For the most part angel investors - that is to say, individuals - have driven the creation of the new industry. VCs turned a blind eye to real value-adding solid-state-lighting startups, instead flocking like sheep to back the worthless wet dreams of the dot.com bubble. • Japanese should ask themselves why, despite the fact that the bright blue light emitting diode originated in Japan, and two of the “big five” manufacturers of gallium nitride LEDs are Japanese, essentially none of the huge surge of related entrepreneurial activity has taken place in Japan.* Almost all the solid-state lighting startups that have popped up over the past few years have been American, Asian, or, interestingly enough, Canadian. Though the regularatory environment in Japan is no longer as hostile to entrepreneurs as it once was, Japanese still have much to learn about how to foster risk-taking and wealth creation. * The Big Five consist of Nichia, Toyoda Gosei, Cree, LumiLEDs, and Osram Opto. To which list Epistar, the leading Taiwanese LED maker, should probably now be added. • For their part, Europeans should stop patting themselves on the back for designing cool new products that incorporate LEDs. Instead, they should ask themselves why, despite the fact that several of the actors in this drama are European by birth, it is possible to write a book such as this essentially without mentioning Europe. Indeed, it is only a slight exaggeration to say that, from a technological and entrepreneurial point of view, regarding LEDs, with the honorable exception of Germany’s Osram Opto, Europe hardly exists. * In more than twenty years of writing about high-tech, I must have met and interviewed thousands of scientists and engineers. Many of them had remarkable tales to tell. But in my experience, nothing matches the extraordinary story of the brilliant Japanese engineer Shuji Nakamura. Indeed, for sheer unlikeliness, nothing even comes close. This book recounts Shuji Nakamura’s inspirational story, much of it told here for the first time. It is based on face-to-face interviews with Shuji himself, whom I first met in 1994 soon after he had made his presence felt and whom I have since interviewed on many occasions, both at Nichia, and at UC Santa Barbara. Also, on numerous interviews with his colleagues, contemporaries, peers, rivals, and students; and on his own writings, most notably his Japanese-language autobiography, Ikari no Bureikusuru [Breakthrough with Anger], which my wife and I translated into English for this project. In addition to chronicling the life of a brilliant engineer, my book also investigates some of the many and various ways Shuji’s brilliant inventions and their derivatives are making their way into our lives, opening up new possibilities, changing forever the way we see our world. Nakamura blew open the floodgates, allowing the creative juices of innovators of all stripes to flow. They include entrepreneurs, philanthropists, designers, architects, and artists who are using solid-state lighting to create new products and eye-catching artworks. For example, navigation lights, emergency lighting, street signs, bus-stops, pocket-sized projectors, water purifiers, adhesive curing systems, portable anthrax detectors, reading lights, light sculptures, ice cubes that light up, buildings that iridesce like squid, and affordable off-grid lighting systems for poor villagers in developing countries, to name but a few. Finally, the book looks at the momentous ongoing revolution that is taking place in lighting. Based on interviews with pioneers in the field, it speculates how LEDs will replace light bulbs and fluorescent tubes, and when and where the change will take place. Shuji Nakamura’s high brightness LEDs are a disruptive technology, happening in real time, right in front of our eyes. The story of their development, commercialization, and application is, ultimately, one of human creativity in all its forms and at its most dynamic. * * * Bob Johnstone has been writing about the impact of technology on society for more than twenty years. The author of We Were Burning: Japanese Entrepreneurs and the Forging of the Electronic Age and Never Mind the Laptops: Kids, Computers, and the Transformation of Learning, Johnstone has been a correspondent for New Scientist, Far Eastern Economic Review, and Wired. He is a former fellow of the Knight Science Journalism Program at the Massachusetts Institute of Technology.
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Domain: Electronics
Category: Semiconductors
Bob Johnstone
28 March, 2007
Bob Johnstone
21 March, 2007
Bob Johnstone
19 March, 2007