ADVERTISEMENT FEATURE PROFESSOR FUJIO MASUOKA Flash memory inventor wins 2018 Honda Prize PROFESSOR FUJIO MASUOKA honored for fundamental contributions to computer engineering Integral to the digital cameras, washing a need to replace magnetic memories and By redesigning cell arrangements of machines, smartphones, and USB bring down the price of storage. NOR flash memory, his team eliminated memories that make our lives easier is A nonvolatile semiconductor memory space between cells and increased the a tiny semiconductor chip called a flash cell is typically made of a silicon substrate density to make the chip more compact memory. Its inventor, Fujio Masuoka, comprising source and drain electrodes and and capacious. Currently, NAND chips professor emeritus of Tohoku University, topped with a floating gate, covered by an dominate the world’s flash memory market, has been awarded the 39th Honda Prize insulation film to trap and retain electrons. and applications have diversified from in recognition of his invention of the By charging and discharging electrons to and digital cameras to solid-state drives as technology that realized large-capacity, from a floating gate, the cell can record and a replacement for hard disk drives. Even nonvolatile memories. The prize is also a erase data. The technology was around as 3D NAND flash memories have recently tribute to his enormous contribution to the early as the 1960s, but its reliability was poor. emerged for use in smart phones. acceleration of technical advancement and Soon after obtaining a doctoral degree Masuoka recalls his ideas were often fostering young engineers in this field. at Tohoku University, then joining Toshiba’s dismissed as “dream-like projects,” but he The Honda Foundation was established Research and Development Center in 1971, was undaunted. He continued to pursue next- in 1977 through the generosity of Soichiro Masuoka invented a more reliable structure generation semiconductor technologies even Honda, founder of Honda Motors, and his by adding a control gate above a floating gate, after he left Toshiba and became a professor brother Benjiro. Since 1980, it has given an which later became the main mechanism for at the Research Institute of Electrical annual prize to individuals or groups who semiconductor-based memories. Communication at Tohoku University. In have shown outstanding achievements But, like other semiconductor 2007, he retired from the university and was in eco-technology development. “Today, manufacturers, Toshiba put all its efforts made a professor emeritus. flash memory diffusion allows for more on DRAM development. Masuoka and his In 2004, Masuoka also became the compact IT devices, and reduced electricity colleagues were no exception, devoting their director and chief technology officer of consumption,” a spokesman for the working hours to upgrading DRAM products, Unisantis Electronics (Japan), now Semicon foundation explained. The award ceremony but working on nonvolatile semiconductor Consulting, where he has been working to was held in Tokyo on 19 November, 2018. memory technologies in their spare time. make planar transistors for integrated circuits Masuoka’s passion and persistence In 1980, Intel announced the world’s first cylindrical to meet growing demand for allowed him to foresee the future market nonvolatile, electrically rewritable memory smaller chips with more capacity. The design, for semiconductor-based memories. Since chip, but it was made of two transistors for which Masuoka conceived as early as 1988, is the 1970s, DRAM (dynamic random access each bit and Masuoka didn’t see a future called surrounding gate transistor (SGT) — a memory) has been the main medium for due to high cost and low capacity. He then silicon pillar surrounded by insulation films storing data and programs on computers hit upon the idea of erasing all bits in blocks and gate electrodes. because of its reading speed and unlimited — like a camera flash — and rewriting on a Masuoka is renowned as a strict and rewriting capacity. But recorded data is per-bit basis by using only a single transistor. excellent mentor for young engineers. “The automatically erased when the power is shut That mechanism allowed him to drastically most important thing for a scientist is to get down, so it is called a ‘volatile memory’. downsize the cell, while increasing the in the habit of thinking from the fundamental, By contrast, a ‘nonvolatile memory’, capacity and reducing the cost by 75% or and take responsibility for the results,” he said. written onto magnetic media such as hard more. In 1984, Masuoka published a paper on disks, can retain data even when the power the world’s first ‘NOR’ flash memory. is off. Usability of nonvolatile semiconductor In 1987, Masuoka announced another memory was far better, but Masuoka saw technology called NAND flash memory. www.hondafoundation.jp/en Advertiser retains sole responsibility for content .