Fullscreen HTML5Med Res (??MB)HTML4

50 YEARS OF THE IN It’s hard to imagine a world without the integrated circuit, just as it is hard to imagine a manufactured product without one! But the IC has only been with us for half a century, being first demonstrated on September 12, 1958. by Ross Tester I t was midsummer, 1958. Jack St Clair Kilby, a recently-employed 35-year-old engineer didn’t have enough leave accrued to take the summer break off like most of his colleagues, so was working virtually alone in the laboratory at Texas Instruments. The most junior engineer at TI, Kilby’s background was in ceramicbased circuit boards and transistorised hearing aids. He joined TI because it was the only company that agreed to let him work on electronic component miniaturization more or less full time – and it turned out to be a great fit. He was working on a problem known in circuit design as “the tyranny of numbers” – the more components a circuit has, the more difficult it is to connect them together using traditional wiring methods. Kilby had come up with an ingenious solution: manufacturing all of the circuit components in a single piece semiconductor substrate. Using a piece of germanium (the Inventor (or co-inventor) of the integrated circuit, Jack St Clair Kilby, in the Texas Instruments laboratory in 2000, the same year he was awarded the Nobel Prize in Physics. Inset top right is Jack Kilby in 1958, the year of his invention. (Pictures courtesy Texas Instruments) 24  Silicon Chip siliconchip.com.au NTEGRATED CIRCUIT The world’s first integrated circuit, September 12, 1958. (Picture courtesy Texas Instruments) then-common semiconductor material) Kilby cobbled together a crude device in the TI laboratory and on September 12, 1958, he presented his findings to Texas Instrument management. His germanium circuit was attached to an oscilloscope, which displayed a continuous sinewave, proving that the concept worked. Thus the integrated circuit was born, ushering in an era that even Jack Kilby couldn’t possibly envisage. “What we didn’t realise then was that the integrated circuit would reduce the cost of electronic functions by a factor of a million to one, nothing had ever done that for anything before,” said Jack Kilby A patent application for “A solid circuit made of germanium” was filed on February 6, 1959. Kilby was awarded the Nobel Prize in Physics in 2000 for “his part in the invention of the integrated circuit”. He siliconchip.com.au had always scoffed at the idea of such an honour, despite many people over the decades suggesting he deserved it – and despite him being awarded just about every other prize and honour available to a humble engineer; one who happened to change the course of history. “Those big prizes are for the advancement of understanding,” Kilby would explain in his slow, plainspoken Kansas way. “They are for scientists, who are motivated by pure knowledge. But I’m an engineer. I’m motivated by a need to solve problems, to make something work. For guys like me, the prize is seeing a successful solution.” Unbeknownst to Kilby, at TI’s great rival Fairchild Semiconductor, co-founder Robert Noyce was also working on a similar concept. Noyce’s approach was different to Kilby’s, using silicon as the substrate, rather than germanium and using aluminium as conducting strips. Noyce’s patent application was filed on July 30 1959, more than five months after Kilby’s. As it happened, Noyce’s approach was much easier to manufacture than Kilby’s and for many years, Noyce claimed to be the inventor of the integrated circuit (as it came to be known), ignoring the fact that Kilby got there first. The first commercially-available integrated circuit was released by Fairchild in 1961. After several years of legal battles, TI and Fairchild wisely decided to cross-license their technologies, creating a global market now worth about $1 trillion a year. These days, both Kilby and Noyce are credited with the invention. In fact, Kilby’s Nobel Prize acceptance speech more than forty years after the invention specifically highlighted Noyce’s achievements. “I would like to mention another right person at the right time, namely November 2008  25 Another of Kilby’s inventions, the first handheld calculator. Robert Noyce, a contemporary of mine who worked at Fairchild Semiconductor,” he said. “While Robert and I followed our own paths, we worked hard together to achieve commercial acceptance for integrated circuits. If he were still living, I have no doubt we would have shared this prize.” Robert Noyce, incidentally, went on to found a small integrated circuit producer called Intel. The IC wasn’t the only device that Kilby invented. At the time of his death in June 2005 (aged 81) he held more than 60 patents. He “officially” retired from TI in 1980 but it has been said that he never really retired, always keeping a very close association with the now-huge organisation. A giant of a man (over 2m or 6’6” tall), Kilby was not much for selfpraise. “My part was pretty small, actually,” he said. Whenever people would mention that Kilby was responsible for the entire modern digital world, he liked to tell the story of the beaver and the rabbit sitting in the woods near Hoover Dam. “Did you build that one?” the rabbit asked. “No, but it was based on an idea of mine,” the beaver replied. After proving that integrated circuits were possible, Kilby went on to head teams at TI that built the first military systems and the first computer incorporating integrated Robert Noyce, today also credited with the “invention” of the integrated circuit, based his design on silicon, rather than the germanium of Jack Kilby. Inset at top is the first commercial IC to come out of Fairchild. 26  Silicon Chip A modern-day silicon wafer. This is more attributable to Noyce than Kilby but both are credited with the invention. (Courtesy Texas Inst). circuits. He also worked on teams that invented the handheld calculator and the thermal printer, which was used in portable data terminals. But it is the integrated circuit which will always be associated with Jack Kilby. As Tom Engibous, Chairman of Texas Instruments said, “In my opinion, there are only a handful of people whose works have truly transformed the world and the way we live in it – Henry Ford, Thomas Edison, the Wright Brothers and Jack Kilby. If there was ever a seminal invention that transformed not only our industry but our world, it was Jack’s invention of the first integrated circuit.” SC Handling wafers in today’s ultra clean-room conditions achieves yields orders of magnitude higher than those in the early days of IC manufacture, where yields of 5% were considered good. siliconchip.com.au