Business Overview and Environmental Issues for Which Risks and Opportunities Have Been Recognized and Evaluated
Delivering Key Devices to Support Our Information Society on a Global Scale
Mitsubishi Electric's Semiconductor & Device Group delivers key devices supporting a sustainable, low-carbon society. Our extensive lineup includes power semiconductor devices for high-efficiency motor control and converting electricity used by home appliances and industrial equipment, high-frequency devices used in everything from wireless communication to satellite communications, optical devices supporting high-speed optical communications, and LCD modules that improve information interfaces. These products are developed and manufactured at the Power Device Works, High Frequency & Optical Device Works and the LCD Division, as well as at out affiliates in and outside of Japan. Each of these facilities is focused on developing low-power consumption products. We are also striving to improve the efficiency of air conditioners as a large amount of energy tends to be consumed during production in order to maintain the high-level clean environment in cleanrooms. In addition, to prevent the depletion and contamination of water resources, we recycle large volumes of pure water used in production processes. We have also introduced chemical substance management systems to properly manage chemical substances in our products.
Environmental Issues for Which Risks and Opportunities Have Been Recognized and Evaluated
- Climate change
- Appropriate use of water
- Proper management of chemical substances
- Conservation of biodiversity
Message from Semiconductor & Device Group
Contributing to the Realization of a Low-Carbon Society by Providing Energy-Efficient Products
In Charge of Semiconductor & Device Group
In order to achieve a sustainable global environment, it is imperative to minimize power loss when generating and using electricity. Power semiconductor devices are key devices playing a significant role in reducing power loss and are being incorporated into power electronics used in vehicles, home electric appliances, rolling stock, and industrial equipment. Products offered by Mitsubishi Electric, the world's No.1 power module manufacturer,*1 are being used all over the world and are contributing to the reduction of energy consumption globally. In addition, Mitsubishi Electric's Semiconductor & Device Group has developed state-of-the-art products using silicon carbide (SiC), which contributes to a sustainable reduction of energy consumed. By enhancing our related businesses and contributing to expanding the market for them, we are helping create a low-carbon society.
To address the issue of reducing the amount of energy consumed by IT equipment, the Semiconductor & Device Group provides high-performance, high-efficiency, and compact high-frequency & optical devices. These devices are employed in gigabit wireless communications equipment and optical fiber communications In addition, not only are we reducing the amount of energy consumed by devices themselves, we are saving space in base stations for mobile communication systems. As a result, the cooling function for communications equipment has been simplified and we are thus contributing to comprehensive energy savings.
Industrial-use TFT color LCD modules provide a mercury-free, low-power consumption option owing to the white LED backlight used in them. Our extensive lineup of LCD modules includes various screen sizes, resolutions, ultrahigh brightness, ultra-wide-viewing angle, and high vibration resistance. They are supplied for a broad range of applications, including measuring equipment, machine tools, POS terminals, vending machines, ticket machines, and in-vehicle and in-vessel displays.
In addition to providing these products, as part of our measures against global warming caused by production, the Semiconductor & Device Group continually and proactively reduces its own energy usage through such measures as employing high-efficiency air conditioners in cleanrooms, where high levels of cleanliness requires a large amount of energy, improving wafer processing operations, and reducing the emissions of non-CO2 greenhouse gases (SF6, HFC, and PFC) through the introduction of detoxifying equipment.
- * For IGBT modules. As of January 2018. In-house review.
Initiatives Contributing to the Environment and Society
Climate change Low-Power Consumption SiC Power Semiconductor Devices
SiC power semiconductor module
Super-mini all-SiC DIPIPM™
Power semiconductor devices have been developed and produced using silicon semiconductors. However, they are believed to be approaching a limit, where it will be impossible to simultaneously achieve an advanced degree of both low loss and high voltage resistance. We are therefore developing semiconductor devices using silicon carbide (SiC), which can significantly contribute to reducing power loss due to the attributes of the material, and expanding the product lineup.
In fiscal 2011, Mitsubishi Electric was the first in the world to equip air conditioners with SiC power semiconductor modules. Since then, we have promoted their use in various products such as rolling stock and industrial equipment. In fiscal 2015, an all-SiC power semiconductor module was used in a rolling stock inverter for the first time. In addition, in August 2016, we launched a super-mini all-SiC DIPIPM*2 that reduces power loss about 70% *1 compared to our conventional products. The product is also used in Mitsubishi Electric air conditioners that have achieved industry-leading low power consumption*3.
In March 2017, we launched the SiC-SBD*4 (discrete), which reduces power loss by about 21%*5 compared to our conventional products. It contributes to improving the efficiency and reducing the size of power supply systems for photovoltaic power systems, air conditioners and more.
We will continue to accelerate the development of new technologies and products to respond to diverse needs for energy efficiency.
- *1 Compared to super mini DIPIPM Ver.6 series (Si product) PSS15S92F6 (15A/600V).
- *2 DIPIPM™: intelligent power semiconductor module incorporating a built-in controlling element with a protective function.
- *3 As of August 17, 2016
- *4 SBD (Schottky Barrier Diode):
- *5 Compared to the Si diode installed in our DIPPFC™ power semiconductor module.
Climate change Development of a Compact Integrated 400Gbps*6 EML*7-TOSA*8 to Support High-Speed Transmissions and Large-Capacity Optical Fiber Communication
Compact integrated 400Gbps EML-TOSA
Data transmission volume has been rapidly increasing with the widespread use of handheld mobile communication devices such as smartphones and tablets, the storage of information on cloud networks. It has become necessary to increase transmission speed and volume in optical fiber communication base stations, including data centers. In response to these needs, we have developed the compact integrated 400Gbps EML-TOSA, which provides transmission at eight different wavelengths by combining TOSA for short wavelengths and long wavelengths (four each). We started providing samples in April 2018. The product realizes lower power consumption for, and smaller design of, communications equipment, which contributes to energy savings.
- *6 Gbps (Gigabits per second): Unit of communication rate. 1Gbps indicates that 1 billion digital codes can be transmitted per second.
- *7 EML (Electro-absorption Modulated Laser diode)
- *8 TOSA (Transmitter Optical Sub Assembly): Compact optical device for transmission.
Climate change Expanding the Lineup of Transflective Series TFT-LCD Modules
Mitsubishi Electric Color Transflective Series TFT-LCD modules
(Left: 8.4-inch VGA, right: 10.4-inch XGA)
Transflective series TFT-LCD modules*9 use outside light as a light source in bright outdoor environments (in reflective mode) and as backlight in dark places (in transmissive mode). Because of their high visibility, even in direct sunlight, and lower power consumption owing to the use of outside light, demand is mounting for use in portable industrial measuring equipment. Expansion of the product lineup will help reduce power consumption of displays installed in a wide range of industrial devices used outdoors.
- *9 Transflective series TFT-LCD modules: TFT-LCD modules that form two different areas (transmissive and reflective parts) within a single pixel and have a structure to reflect outside light on a substrate.
Initiatives for Reducing Environmental Impact
Climate change Making Cleanrooms More Energy Efficient
The manufacturing of semiconductors and devices is conducted in cleanrooms under rigorous temperature, humidity, and cleanliness controls to ensure product quality and reliability. Maintaining such a high-level cleanroom environment requires air conditioners that consume as much energy as production equipment. These circumstances led to our decision to take every possible step to reduce energy consumption; for example, by replacing conventional air conditioners with high-efficiency units and improving the efficiency of wafer processing equipment.
Use of High-Efficiency Air Conditioners
Our Power Device Works at the Kumamoto site has changed over to higher efficiency air conditioners and integrated management, resulting in a 16.6 million kWh (equivalent to 7,000t of CO2) reduction in annual electricity consumption.
Installation of Photovoltaic Systems
A rooftop photovoltaic system with a rated power output of 300kW has been installed at our Power Device Works at the Fukuoka site, resulting in a total reduction in consumption of approximately 290,000 kWh (equivalent to 120t of CO2) per year.
Installation of Ice-Based Thermal Storage System
The LCD Division uses nighttime power to create ice for its ice-based thermal storage system. Cold energy stored in the ice is then used for air conditioning. This system helps us reduce the division's electricity usage and realize a peak shift, in response to requests from Japanese government and power companies.
Installation of Yellow LED Lamps
At the Power Device Works and High Frequency & Optical Device Works, we have been systematically moving toward LED lighting. In fiscal 2016, we installed practical-use LED yellow lamps, which affect manufacturing conditions, for verification purposes as well. This realizes a 650,000 kWh (equivalent to 275t of CO2) reduction in annual electricity consumption. Further conversions to LED lighting are planned for the future.
Climate change Focusing on Reducing Energy Consumption in Office Buildings by Combining Our Best Energy-Saving Technologies
The design technology building at the Fukuoka-based Power Device Works is equipped with various environment-conscious features, including Mitsubishi Electric's own Facima system, which controls and manages energy consumption. This building has been recognized for its high environmental performance and was awarded the highest evaluation of "S Rank" under Fukuoka CASBEE*, a system that evaluates the environmental performance of buildings. Moreover, a new technological control building for the LCD business also earned the recommendation rank of "A (very good)" under Kumamoto CABEE, in recognition of its high environmental performance.
- * CASBEE: Comprehensive Assessment System for Built Environment Efficiency. A standardized Japan-wide evaluation system jointly developed by industry/government/academia that ranks buildings according to their environmental performance.
Appropriate use of water Focusing on Water Recycling and Preventing Contamination from Wastewater
Semiconductor production factories use large volumes of pure water. From the viewpoint of preventing further depletion of water resources, we are making efforts to reuse pure water. As part of this, we ensure removal of organic and inorganic contaminated impurities contained in the wastewater, and have established a system to process and recycle effluent.
Proper management of chemical substances Thorough Management of Chemical Substances
In order to quickly and accurately respond to customer inquiries related to information on the environmental impact of our products, we have introduced a chemical substances management system.
Conservation of biodiversity Promotion of Activities for the Conservation of Biodiversity
We started a biological research project involving animals and plants at our Power Device Works and High Frequency & Optical Device Works in fiscal 2016. As a result of examining the animals and plants living at these sites with expert guidance, we were able to confirm the presence of many regional endemic species, including some living organisms designated as endangered species. We will conduct activities designed to improve the growing environment for these local species.
Additionally, we also produced a living creature guide at the Power Device Works and distributed it to nearby elementary schools and neighborhood community associations. We are also working to live in harmony with the local communities, giving due consideration to biodiversity.