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Illuminating the 21St Century with the Blue LED an Energy Revolution in Lighting

Illuminating the 21St Century with the Blue LED an Energy Revolution in Lighting

2014 No.55

Reporting on Today and Tomorrow’s Energy, Environmental and Industrial Technology

[Featured Article] Illuminating the 21st Century with the Blue LED An Energy Revolution in Lighting

Special Dialogue “2014’s Gives Courage to Engineering Graduates” (Professor, Graduate School of Engineering, ) × Kazuo Furukawa (NEDO Chairman) Contents What is an LED? An LED (Light Emitting Diode) is a type of device composed of p-type and n-type 2014 no.55 . When direct electrical current flows through [Featured Article] the junction between these two 02 types of semiconductors, part of Illuminating the electrical energy is converted st and emitted as light. The light the 21 color changes depending on the semiconductor materials used. Century In comparison to conventional incandescent bulbs and fluorescent with the Blue lamps, LEDs have distinguishing features such as smaller size, the The deployment of LEDs ability to function as a point light LED Colorful display of electronic billboards and large-scale in indoor lighting and street source, longer service life, and An Energy Revolution in lower power consumption. The displays is made possible by the development of blue LEDs. lights is progressing rapidly. NEDO “Development of Lighting market for compact LED lamps of the kind first developed around Compound Semiconductors for 2003 grew rapidly due to energy- High Efficiency Optoelectronic saving measures after the Great Light emission phenomenon observed White LED East Earthquake in 2011. when voltage applied to SiC High-intensity blue created by Conversion (Light for the 21st (silicon carbide) LED created using combining Century Project)” aims for a light-emitting a blue LED improved energy conservation Yellow-green layer of InGaN and a yellow with luminous efficiency of History of LED LED (indium gallium nitride) phosphor 80-100 lm/W. Development

1879 1961 1989 1995 2002 1998-2003 2010-2014 1907 1968 1993 1996 04 Special Dialogue “2014’s Nobel Prize Award Gives Courage to Incandescent light bulb Red LED “PN junction” Green LED White LED NEDO “Fundamental Engineering Graduates” created using created using created by combining Technology Development Hiroshi Amano p-type light-emitting an ultraviolet Project of Next-generation (Professor, Graduate School of Engineering, Nagoya University) [Featured Article] GaN (gallium nitride) layer of LED and an RGB High-efficiency and High- × InGaN phosphor quality Lighting” aims for Kazuo Furukawa st significantly improved (NEDO Chairman) energy conservation with Illuminating the 21 a goal of luminous 08 NEDO Project Overview efficiency over 200 lm/W. Achieving High- efficiency LED Lights Changes in Domestic Shipments of Lighting with an Efficient Method Century with the Equipment (millions of yen) for Growing GaN 700,000 LED lighting equipment Crystals In recent years LED lighting has spread rapidly! Electric-discharge lamp equipment Disaster prevention equipment Incandescent lamp equipment Blue LED 600,000 10 Special Report Fluorescent lamp equipment Toyoda Gosei Co., Ltd. An Energy Revolution in Lighting As LEDs have become 500,000 Developing LED used in the backlights of Business as a Second The invention of the blue LED that won the Nobel Prize for Physics mobile phones and tablet Core Business to Follow in 2014 has led to the creation of energy-saving light bulbs to computers, the market 400,000 has become huge. Automobile Parts replace conventional incandescent bulbs and is changing the world 300,000 of household and industrial lighting. Lighting currently accounts for 12 NEDO Project Overview nearly 20% of household and office power consumption, and if the use Creating an Even More 200,000 of extremely high-efficiency LED lighting expands, it can promote Favorable Environment energy conservation on a global scale. This featured article covers the for Developing Next 100,000 Generation Power latest information on energy-saving lighting, including NEDO’s projects involved in the development of blue LEDs, as well as next-generation Electronics with 2014’s 0 Nobel Prize Award power electronics. 2009 2010 2011 2012 2013 Source: Japan Lighting Manufacturers Association (FY2013 data)

02 2014 no.55 03 Special Dialogue Dialogue Professor, Graduate School of In 2014, three Japanese scientists who Featured Article Engineering, Nagoya University conducted research and development in “2014’s Nobel Prize LED technology received the Nobel Prize Award Gives Courage (Director, Akasaki Research Center, Nagoya University) to Engineering for Physics. One of the three, Professor Graduates.” Hiroshi Amano of Nagoya University’s Hiroshi Amano Graduate School of Engineering, has been involved with NEDO and has worked together on a project with NEDO in the past. After receiving news that Professor Amano had won the Nobel Prize, Chairman of NEDO Kazuo Furukawa sat down with him NEDO Chairman for an in-depth conversation. They discussed the backstory of Amano’s prize-winning Kazuo Furukawa research and future developments in LED research, as well as the current situation facing university engineering departments.

theoretical physics to win. As someone who also graduated in LED Research Became a Big Success engineering, I think that your winning this award gives all the Thanks to a Device Failure people working in the engineering community a great amount Furukawa: We truly want to congratulate you on receiving of courage. 2014’s Nobel Prize for Physics. First I would like to ask you Amano: I also think that it’s great that the Nobel Prize shone about the significance of receiving the Nobel Prize. In the some light on our School of Engineering. At the beginning press release that was released by the Royal Swedish Academy we didn’t have enough funding and buying materials. So our of Sciences, it says “The LED lamp holds great promise for experimental equipment was homemade. We took parts from increasing the quality of life for over 1.5 billion people around old devices and an unused rotary pump from another research the world who lack access to electricity grids: due to low power laboratory, and used them to assemble our equipment. After requirements it can be powered by cheap local solar power.” that we had to build a device to show that it could produce light Professor, what are your feelings about this? well in order to appeal to the world. At that time I conducted Amano: The image I always used to hold of the Nobel Prize demonstrations through NEDO project and this enabled my was that it was an award intended for theoretical like work to gain global attention. NEDO really helped greatly. It Professors , Toshihide Masukawa, and Makoto is truly thanks to NEDO that I have been able to attend many Kobayashi in the case of Japanese laureates. I now feel that the international conferences and present my findings and data. Professor, Graduate School of Nobel Prize has gradually started recognizing achievements Furukawa: I am very happy to hear you say that. Your Engineering, Nagoya University that are more familiar and useful to people. The energy-saving invention – inserting a buffer layer as a substrate to cause (Director, Akasaki Research Center, Nagoya University) Hiroshi Amano impact of LED is tremendous, and it is expected that about growth GaN layer – was a really innovative one for us, but 70% of the lighting in Japan will become LED by the time of was this kind of method something that you had been thinking Born in City, Shizuoka Prefecture. Graduated from School of Engineering, Nagoya University in 1983. Completed the Tokyo Olympics in 2020. If that happens, LEDs will result about from the beginning? doctoral coursework at Nagoya University but withdrew from studies in 1988. Received his doctoral degree in engineering in energy savings equivalent to 7% of total power generation. I Amano: No, not at first. Since we couldn’t manage to create in 1989. Became a Professor in the Faculty of Science and felt extremely lucky in a sense to have a spotlight on this kind well-formed crystals, I wondered if there might be a need to Engineering at in 2002. Later became a Fellow at the Japan Society of Applied Physics in 2009 and then a Professor of lighting and I am truly happy about it. sandwich the crystals with something else. At that time there in Graduate School of Engineering at Nagoya University in 2010. Received the Nobel Prize for Physics in 2014 based on his research Furukawa: Actually, I also thought that the Nobel Prize was another person in the same research laboratory who was on blue LEDs. Also received the and selected as a for Physics would be hard for people who were not in researching aluminum nitride crystals and I realized that they Person of Cultural Merit in the same year (as of November 2014).

04 2014 no.55 05 Special Dialogue “This Year’s Nobel Prize Award Gives Courage to Engineering Graduates.”

were forming well, so at that point I thought that I’d try using potential of GaN is high, but unfortunately the substrate immediately fall asleep. This technology would also be useful unfortunate thing is that the majority of the doctoral students that as a buffer layer. However, aluminum nitride doesn’t technology is still inferior when compared with SiC. If we in treating people with conditions involving numbness in a have become foreign students from abroad. They return to cleanly form a single crystal unless it is created at a high don’t resolve this issue, we won’t be able to achieve reliability. limb. I have a dream of working on this together with people their countries once the doctoral program is completed, which temperature. As it happens, the kiln occasionally wouldn’t Given that power devices are used in ways that impact people’s involved in medical and physical science research. is too bad. I’d like Japanese companies to take more advantage work properly and the temperature would only go up to 800- lives, they need to have high reliability - in other words, we of these foreign students. And I’d like more Japanese students 900℃. So I tried attaching the buffer layer at low temperature. need to establish technology to make better crystals that will Fostering Future Nobel Prize Winners to remain among doctoral course. This was ultimately a big success. Although that was one of lead to the breakthrough material to replace silicon. I would through Personalized Programs Furukawa: This is certainly a difficult problem. NEDO has the techniques that I had been thinking about, but actually it really like to make it a reality. If it happens, it could save Furukawa: They say now that student’s interests are moving begun a new program in 2014. In this program we provide occurred because the device was broken. (Laugh.) energy comparable to half the power generated by nuclear away from science and engineering, but what do you think that support for individual living expenses and research funding power plants in Japan because the power loss is approximately we should do? I still haven’t figured this out myself, but do you in the amount of 6 million to 15 million yen (50,000-125,000 The Wide Range of Applications for LEDs 1/6th compared to silicon. I have a dozen years or so until my have a secret plan in mind? USD) per year. In this fiscal year we plan to provide 15 awards, Continues to Expand retirement, and I want to pave the path by then. Amano: We have been offering special science classes at but we received 400-500 applications. Furukawa: I would like to hear about the future development Furukawa: Do you have anything else other than GaN and elementary schools as part of academic society activities, and Amano: It would be great if NEDO expands that program of the blue LED. And in terms of GaN (gallium nitride), it LED that you want to work on? they have been very popular. We receive twice the number of further. If they could somehow get research and living expenses, seems that there are also expectation that it will succeed SiC Amano: Although it’s related to LEDs, one thing I’m very applications we can handle every time, and the eyes of the I think that there would be more than a few students who would (silicon carbide) as a material for power semiconductors. interested in is plant. I think that it would be a very strategic children who participate are shining as they perform science stay on in the doctoral programs. I’ll have to encourage our Amano: There are still many things that I’d like to do. In terms system to export plant factories to countries that cannot grow experiments. So in terms of interest, elementary school children postdoctoral researchers to apply as well. (Laught.) of LED, although it has expanded up until now, I think that crops due to deserts and so on. Another thing that I find probably haven’t changed. Rather I think it is stronger now. Furukawa: Since NEDO wants to try a number of different there is still a lot of room for growth. Particularly in terms interesting is controlling animal behavior at the molecular level However, when it comes to middle and high school students, approaches going forward, we would really appreciate your of efficiency where we have achieved 60%, but it is still not by lighting. It has already been shown in mice that making a they suddenly stop interest. So I feel that we should take some continuing guidance. It would be great if a Nobel Prize winner 100%. In regard to color, I also feel that we want to aim for protein light sensitive can be used to activate or relax the brain. actions to solve this during middle and high school. like you emerges from NEDO programs in the future. getting 100% efficiency freely from any color of LED. For example, we have idea to insert LED in a person’s brain When I look at the situation with university students, it hasn’t Right now we are conducting research at the university into and turn on the switch only at times we wish to activate it. It really changed compared to the past. On the contrary, college next-generation LEDs that take advantage of the structure is becoming a reality that when you want to put yourself to students today understand the content of their studies and of nanowires. We are also working on power devices. The sleep you can flip the switch on an orange-colored light and they are well-engaged in research and experiments. But the

06 2014 no.55 07 NEDO Project Overview

Achieving High-efficiency LED What is a Gallium Nitride Substrate? Lights with an Efficient Method for Growing GaN Crystals In an LED, light is emitted from an LED chip Typical LED Structural Diagram Global warming has become a worldwide issue. To help cope with this, NEDO engaged in created by growing a GaN (gallium nitride) the development of LED lighting technology to achieve significant efficiency improvements, Project Coordinator, Electronics, crystal on a substrate. The most common through the “Fundamental Technology Development of Next-generation High-efficiency and Materials Technology and substrate in LEDs found on the market today is p-type semiconductor High-quality Lighting” project from FY2009 to FY2013, with an eye towards energy saving in Nanotechnology Department, NEDO sapphire, which is called “sapphire substrate.” lighting which accounts for approximately 20% of power consumption in the home and office. n-type semiconductor Nobuyuki Takai However, in theory, it is known that growing GaN on a GaN substrate composed of the same Substrate elements as opposed to on a sapphire substrate High-efficiency LEDs Can Achieve a Low- and his affiliated Nagoya University, we also asked Osaka results in better product quality, higher efficiency Energy Lighting Society University, Toyoda Gosei Co., Ltd., Ricoh Company, Ltd., when emitting light, and a brighter LED. This Innovation Center Inc., Mitsubishi Chemical Corporation, substrate is called “GaN substrate”. Sapphire substrate

Global warming is an important issue that every country in the Citizen Electronics Co., Ltd., NEC Lighting, Ltd., Mitsubishi Although the method for efficiently producing GaN crystal world should be tackling with. Given that lighting consumes Plastics, Inc., Tohoku University, EL-Seed Corp. and Meijo GaN substrate was not established until recently, Sapphire nearly 20% of all electricity in the home and office, in order University to engage in research and development. GaN crystal growth technology has been Isolated for use as to solve the problem of global warming it is essential to create developed by 2014’s Nobel Prize winner in GaN substrate a substrate Project Results energy savings in lighting applications. Physics, Professor Amano. GaN crystal LED lighting that has appeared in the 21st century is expected An efficient method of growing GaN crystals was developed GaN to be the next generation of high-efficiency lighting to support in this project. As a result, NEDO developed the technology energy conservation in the lighting society of the future, to efficiently generate a GaN substrate and achieve extremely Using the same materials, it is possible to grow higher quality crystals. although it still can’t be called efficient enough. high-efficiency LED lighting. Through “Fundamental Technology Development of Next- An expanded range of applications such as high ceiling generation High-efficiency and High-quality Lighting” project lighting, projectors, and automobile headlights are expected (FY2009-FY2013), NEDO worked to develop LED lighting for the high-efficiency LEDs that make use of these results. In GaN Substrate technology to achieve significantly improved efficiency with addition, if GaN substrates are used outside of LED lighting, LED Lighting over twice the light emission efficiency of fluorescent lighting. applications are anticipated such as small-scale, high-output Manufacturing The manufacturing process from the production of the substrate to the electronic devices for automobile controls, next-generation Process production of an LED lamp. Project Efforts Focusing on mobile base stations, and energy-saving consumer electronics. Generating GaN substrates can achieve high efficiency, bright LEDs. Commercialization Although LED lighting with sapphire substrates has been Realizing both high quality and GaN substrate LED package LED lighting rapidly popularized in Japan, it has been known since 2009 large diameter GaN crystals with the new HVPE production GaN crystal that there are theoretical limits to LED efficiency improvement method with sapphire substrates. Although significant efficiency (Mitsubishi Chemical Corporation) improvements would be possible if a GaN (gallium nitride) GaN crystal substrate produced substrate is achieved, the technology for manufacturing GaN with the Na flux production substrate had not been established. Furthermore, even if GaN method substrates are possible, if the manufacturing costs are still very (Osaka University) high, it would be hard to sell them to the general consumers Inducing the growth of The crystals that are N-type and p-type The LED package is and energy savings would not move forward. GaN (gallium nitride) grown are cut thinly to be semiconductor layers are combined with an optical What was needed was technology to induce the growth of GaN crystals to use as a used as the substrate. formed, and the resulting lens and a power supply substrate for high- lighting element is to create a finished LED crystals that form the basis of the GaN substrate and efficiently High-efficiency LED lighting efficiency LEDs. packaged with a phosphor lamp. produce them. Furthermore it was also necessary to develop created on a GaN crystal on the substrate. technology to achieve high efficiency utilizing the GaN substrate substrate effectively. In order to resolve these issues, the project (Nagoya University) Photos (left to right): Mitsubishi Chemical Corporation, Citizen Electronics Co., Ltd., NEC Lighting, Ltd., Mitsubishi Plastics, Inc. worked to develop GaN substrate crystal growth technology, optical designs, heat dissipation designs, circuit designs, and so on. In addition to Nobel Prize laureate Professor Amano

08 2014 no.55 09 Special Report Toyoda Gosei Co., Ltd.

Developing LED Business as a Second Core Business to Follow Automobile Parts

Toyoda Gosei Co., Ltd. is a global leader in blue LED manufacturing, sales, research and development. Nonetheless, its history was one a series of trials and errors. As a result of tenaciously continuing research and development, they now have business that has grown to nearly 50 billion yen in annual sales. The market is predicted to expand even more in the future and Toyoda Gosei is hoping that their LED business will grow too.

(Left) Demonstration test machine for manufacturing GaN substrates being developed in collaboration with NEDO. (Center and right) A tester verifies the GaN substrates grown by the test machine

succeed.” Shortly after, they succeeded with the development of high-efficiency LED, and there are plans for the introduction of blue LEDs in 1991. “I was told that the first time it lit up, everyone automobiles equipped with headlights using Toyoda Gosei’s LEDs. Managing Officer General Manager of Optoelectronics in the place gave a cheer. There are a lot of anecdotes about the The company is also focusing on increasing the lineup of interior Business Unit development of blue LED,” commented Managing Officer Yasushi and exterior parts for automobiles that employ LEDs. Yasushi Miyamoto General Manager of Miyamoto with emotion in his voice. In the midst of this process, the company participated in a project Research and Development with NEDO beginning in 2004 that has spanned 10 years. “Initially Division Aiming to Expand Business with an it felt like we were groping in the dark, but now I feel confident Kozo Arao Additional Focus on Automobile that we can produce some good things. If it weren’t for the industry- Applications university collaboration through the NEDO project, I don’t think The first products to adopt LEDs were large-scale displays, and that we could have reached this point alone,” commented General Toyoda Gosei’s LEDs were used in the display at the National Manager of Research and Development Division Kozo Arao. Stadium in Tokyo. After this, applications spread rapidly, beginning Low-cost, high-efficiency GaN substrate LEDs have the potential to with traffic signals and then expanding to use in backlights for change the world. While it reviews its research results with NEDO, personal computers, tablet PCs and smart phones. “As backlights of Toyoda Gosei plans to continue pushing on with LED product high-definition liquid crystal display panels in personal computers development. and mobile devices, small, high-efficiency LEDs are very popular and those including lighting applications account for 50 billion yen (417million USD) in sales. Although there was a difficult period for This interview was conducted in 2014. the business, now it is second only to our automobile parts business,” That was when he met Professor Akasaki. This visited commented Managing Officer Miyamoto happily. Extensive Research Began with Meeting One of Toyota Gosei’s LED products Professor Akasaki and proposed doing joint research. Although he The growth of the overall LED market continues to climb and it (internal structure of fluorescent lamp- Professor Akasaki visited Professor Akasaki many times he was not able to obtain a is expected that the market will exceed 1 trillion (8.3billion USD) type LED lighting). “Please let me do blue LED research and development.” positive commitment, but after being urged by Masao Nemoto, and some hundreds of billion yen in the future. However, in recent That’s what one Toyoda Gosei engineer said in the middle of the Toyoda Gosei’s president at the time, joint research on the GaN years the competition has been getting increasingly intense with 1980s. He had attended lectures by Professor of (gallium nitride) compound semiconductors that enable blue light Taiwanese, Korean, and Chinese companies entering the market. Department of Electronics in the School of Engineering at Nagoya emission finally began. That was in 1986. “The goal of our company is to offer high value-added LEDs, University (currently Distinguished Professor at Nagoya University Still, in the first five years they were not able to produce pursuing high-efficiency in consultation with our customers and and University Professor at Meijo University), grew interested in semiconductors that emit light. For this reason there were voices in through a business model focused on creating things our customers blue LEDs and discussed this with his supervisor. the company asking, “Why don’t you quit?” At that time, President want,” emphasized Mr. Miyamoto. “Eventually, we’d also like to At the time, Toyoda Gosei was considering the launch of a new Nemoto encouraged everyone saying, “We’re trying to do something expand into products related to automobile headlights and onboard business line to follow automobile parts, the company’s core for the first time in the world, and it’s important that we don’t jump automobile equipment to expand our sales.” business which consisted of rubber and plastic parts for automobiles. to conclusions and we face this believing that we will absolutely Already they are working on the development of a high-power,

10 2014 no.55 11 NEDO Project Overview Predicted Breakdown of Power Devices by Prospective Fields

Reduction in the numberdevices of the in Reduction * Large changes are possible due to future technological developments 100M SiC Linear Creating an Even More Favorable Bulk power system 10M Bullet trains Environment for Developing Next Power distribution system equipment

Generation Power Electronics 1M Trains Inverters for GaN

Device power conversion capacity P (VA) industrial with 2014’s Nobel Prize Award equipments and 100K motors HEV/EV Power electronics are being used to utilize electric power more efficiently and without waste. NEDO Electronics, Materials Technology and Nanotechnology Switching power NEDO is working on development of next-generation power electronics to make things even Department supplies and servers 10K more efficient. Having a Japanese researcher receive 2014’s brings high Household (PFC circuits) Power Electronics electronics expectations for further accelerated development in this area. General- High power Next generation Project Team purpose wireless electrical cellular base stations inverters 1K Automotive electronics equipment (5G compatible) OA equipment Microwave VHF/UHF radio Terrestrial ovens AC adapters digital broadcast Microwave 100 transmission Mobile Satellite communications communications Contactless base stations power supplies 10 and electric chargers Fixed wireless Next Generation Si Mobile devices Automobiles are Expanding 1 100 1k 10k 100k 1M 10M 100M 1G 10G 100G

Operating frequency (Hz) Miniaturization of modules

the way in regard to GaN. It became possible to efficiently around several thousands. grow well aligned crystals using the method Professor Amano NEDO believes that it is important to create a plan for offering discovered, and these results have allowed many researchers to high quality materials, and that providing materials to Japanese work on GaN and enabled the creation of the blue LED. companies is one part of our mission. NEDO hopes that in Although blue LEDs are now being used in many areas, their only a few years after the project completion the development use in power electronics will require the production of more results will be put to practical use. well aligned (higher quality) crystals. With this goal in mind, The range of applications is broad in a variety of areas such NEDO is moving forward with “SIP/Next Generation Power as electric vehicles, household electronics, battery chargers, Electronics Project.” Just as when blue LED became possible, and communications base stations. One interesting path for NEDO hopes that many researchers will come to work on utilization is robotics. Until now inverters were too large to the development of next generation power electronics thanks be installed in robots, but if next generation power electronics Application in the Rail to 2014’s Nobel Prize award, accelerating its emergence in with GaN and other materials are used, these can become Sector is Progressing commercial products. extremely small and it becomes possible to have robots that move in ways more closely resembling humans. Eventually, have gained attention as candidates for materials for next- An Unlimited Range of Applications, Even robots will be able to jump in the future. Professor Amano’s Breakthrough Research generation power electronics. Compared to Si, these materials Electric Airplanes Could Be Possible Furthermore, electric airplanes and electronic boats might Opened the Way have special characteristics such the ability to carry high The GaN project has just begun in 2014. The length of the become a reality. Although there is already an electric boat NEDO believes the fact that a Japanese researcher received voltage, low power loss, and the potential for miniaturization. project is 5 years with participating members from 5 Japanese equipped with Si inverters, it is by no means satisfactory since the Nobel Prize in Physics 2014 will provide momentum in For example, compared to Si, SiC can have one-half the power companies and 8 universities as well as the National Institute the inverters are too large. In the case of airplanes, planes that the area of next-generation power electronics research. Within loss and the volume can be one-fifth as large. The potential of of Advanced Industrial Science and Technology (AIST). The run only on the power provided by solar panels attached to the the many different electronic devices that are being used in GaN as a material is believed to be even greater. emphasis is on improving quality of GaN crystals and lowering fuselage might become routine. many products around us, if the CPU or memory is likened However, with SiC and GaN, it is extremely difficult to force costs. In terms of cost, although the cost of GaN is currently These types of next-generation power electronics hold to a brain, then power devices serve as the muscles, and for two different elements like silicon and carbon or gallium 10-20 times that of silicon, at the very least NEDO wants these tremendous potential and NEDO is promoting research and this reason they are extremely important. Currently, 99% of the and nitrogen, respectively, to grow properly aligned crystals costs to be reduced to approximately twice the cost of silicon. development of not only GaN but also Si and SiC with the total power devices are made from Si (silicon). and it was not easy to achieve. 2014’s recipient of the Nobel Furthermore, for quality improvements, NEDO hopes to same priority. NEDO wants to go forward by identifying NEDO is currently engaging in research and development Prize in Physics, Professor Amano of Nagoya University’s reduce the number of defects from the crystal growth process which of these materials might be appropriate for applications of SiC (silicon carbide) and GaN (gallium nitride) which Graduate School of Engineering, was the one who opened from the current state of 1 million per square centimeter to in what kinds of fields.

12 2014 no.55 13 Domestic Offices

Head Office Kansai Branch Office MUZA Kawasaki Central Tower, 16F-20F Umeda Dai Building, 6F, 3-3-10 1310 Omiya-cho, Saiwai-ku Umeda, Kita-ku Kawasaki City, Kanagawa 212-8554 Japan Osaka 530-0001 Japan Tel: +81-44-520-5100 Tel: +81-6-7670-2200 Fax: +81-44-520-5103 Fax: +81-6-6344-4574

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New Energy and Industrial Technology Development Organization MUZA Kawasaki Central Tower, 1310 Omiya-cho, Saiwai-ku Kawasaki City, Kanagawa 212-8554 Japan Tel: +81-44-520-5100 Fax: +81-44-520-5103 URL: http://www.nedo.go.jp/english/index.html August 2015