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More for IoT: our natural roadmap says Cypress’ CEO By Julien Happich After completing the USD 4 Billion all-stock 50%-split Cypress-Spansion merger, CEO T.J. Rodgers is to head the post-merger company under the global name Cypress, albeit with Spansion’s world leadership in NOR Flash memory while retaining Cypress’ huge SRAM memory market. When asked about possible product line consolidations (both companies offer memory and ARM-based MCUs for the automotive market), Rodgers emphasizes the complementarity of the two companies. “Of course, there may be some overhead and duplication of sales forces, but on the R&D front, all our programs will continue unaffected on both sides, without any cuts”, Rodgers told EETimes Europe. Within three years, the merger is expected to achieve more than $135 million in cost synergies on an annualized basis. “We’ll be able to exchange more IP and that will certainly open up new ventures, but there is virtually zero duplication between our product portfolios. One of the benefits of this merger is precisely that Cypress and Spansion’s lines of MCUs are almost complementary. There is no negative revenue synergy”. Even if both companies were already present individually in the automotive market, Rodgers explained that while Cypress tends to address embedded system solutions in the cockpit, with touch-screen interfaces, Spansion’s products find their way into car engine management. As for the memory markets that the two companies served (Spansion will retain its own name in the merger), Rodgers expects that cross-channel selling will expand the whole company’s memory business. Remaining on board as one of the four Spansion directors, John Kispert (formerly CEO at Spansion) highlighted that the resulting company has all the essential building blocks to address factory automation, next generation connected cars, and to fuel the growth of IoT. “When we started our conversation Rodgers and I, we realized that by putting our companies together, we would see a wonderful roadmap in the growth of IoT”, Kispert said, although a joint growth plan for the post-merger company has not been formalized yet. “If we lay out our combined portfolio, we now truly have a one-stop shop for our customers, so we become a more strategic supplier. We eliminate multiple sources and this makes it easier for them too” added Rodgers, “as one company, we have doubled our number of customers”. Computer simulation cues for blue LEDs By Paul Buckley Scientists at Univeristy Colege London (UCL), in collaboration with groups at the Univeristy of Bath and the Daresbury Laboratory, have used computer simulations of gallium nitride to shed fresh light on the mystery of why blue LEDs are so difficult to make. The key ingredient for blue LEDs is gallium nitride, a robust material with a large energy separation, or ‘gap’, between electrons and holes - this gap is crucial in tuning the energy of the emitted photons to produce blue light. But while doping to donate mobile negative charges in the substance proved to be easy, donating positive charges failed completely. The breakthrough, which won the Nobel Prize for the in ventors of blue LEDs, required doping it with large amounts of magnesium. “While blue LEDs have now been manufactured for over a decade,” explained John Buckeridge (UCL Chemistry), lead author of the study, “there has always been a gap in our understanding of how they actually work, and this is where our study comes in. Navely, based on what is seen in other common semiconductors such as silicon, you would expect each magnesium atom added to the crystal to donate one hole. But in fact, to donate a single mobile hole in gallium nitride, at least a hundred atoms of magnesium have to be added. It’s technically extremely difficult to manufacture gallium nitride crystals with so much magnesium in them, not to mention that it’s been frustrating for scientists not to understand what the problem was.” The team’s study, published in Physical Review Letters, unveils the root of the problem by examining the unusual behavior of doped gallium nitride at the atomic level using computer simulations. “To make an accurate simulation of a defect in a semiconductor such as an impurity, we need the accuracy you get from a quantum mechanical model,” explained David Scanlon (UCL Chemistry), a co-author of the paper. “Such models have been widely applied to the study of perfect crystals, where a small group of atoms form a repeating pattern. Introducing a defect that breaks the pattern presents a conundrum, which required the UK’s largest supercomputer to solve. Indeed, calculations on very large numbers of atoms were therefore necessary but would be prohibitively expensive to treat the system on a purely quantum-mechanical level.” The team’s solution was to apply an approach pioneered in another piece of Nobel Prize winning research: hybrid quantum and molecular modelling, the subject of 2013’s Nobel Prize in Chemistry. In these models, different parts of a complex chemical system are simulated with different levels of theory. “The simulation tells us that when you add a magnesium atom, it replaces a gallium atom but does not donate the positive charge to the material, instead keeping it to itself,” said Richard Catlow (UCL Chemistry), one of the study’s co-authors. “In fact, to provide enough energy to release the charge will require heating the material beyond its melting point. Even if it were released, it would knock an atom of nitrogen out of the crystal, and get trapped anyway in the resulting vacancy. Our simulation shows that the behavior of the semiconductor is much more complex than previously imagined, and finally explains why we need so much magnesium to make blue LEDs successfully.” The simulations fit a complete set of previously unexplained experimental results involving the behavior of gallium nitride. 22 Electronic Engineering Times Europe January 2015 www.electronics-eetimes.com


EETE JAN 2015
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