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Company

Environment – Semiconductor & Device Group

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 devices for the high-efficiency motor control and electricity conversion of 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, the LCD Division, and their affiliates in and outside Japan. Each of these facilities is focused not only on developing low-power consumption products with minimized loss but also on implementing energy-efficient manufacturing solutions. Since semiconductor factories tend to consume large amounts of electricity to maintain a clean environment in clean rooms and to perform advanced production processes often requiring a large amount of energy, we continuously reduce energy consumption through such measures as introducing high-efficiency air conditioners. In addition, to prevent the depletion and contamination of water resources, we recycle and reuse 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 in operating areas
  • Proper management of chemical substances in design and manufacturing
  • Conservation of biodiversity in operating areas
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Message from Semiconductor & Device Group

Contributing to the Realization of a Low-Carbon Society by Providing Energy-Efficient Products

Toru Sanada
Executive Officer
In Charge of Semiconductor & Device

In order to achieve a sustainable global environment, it is imperative to minimize power loss when generating and using electricity. Power modules are key devices playing a significant role in reducing power loss and are being incorporated into home electric appliances, rolling stock, and industrial equipment. Products offered by Mitsubishi Electric, the world's No.1 power module manufacturer, are being used all over the world and are contributing to a reduction in energy consumption globally. In addition, Mitsubishi Electric's Semiconductor & Device Group has developed state-of-the-art power modules using silicon carbide (SiC), which contributes to a sustainable reduction of the energy consumed when compared to conventional silicon (Si) products. By enhancing the lineup of these power modules and expanding the market for them and our related businesses, we are contributing to reducing carbon emissions further.

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 realized by our compound semiconductor device technologies are employed in gigabit wireless communications equipment and optical fiber communications, reducing the amount of energy consumed by IT equipment to ultralow levels. In addition, not only are we reducing the amount of energy consumed by devices themselves, we are also developing devices that reduce the electrical power required for cooling base stations, promoting a reduction in energy use by the IT industry as a whole.

In the field of TFT LCD modules, we employ mercury-free, energy-saving white LEDs in TFT color LCD modules. Our extensive lineup of color TFT LCD modules includes various types from standard products to outdoor products featuring ultrahigh brightness. They are supplied for a broad range of applications, including POS terminals, vending machines, ticket machines, displays for banks, and in-vehicle & in-vessel displays.

In addition to focusing on the development of these low-power consumption 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, improving wafer processing operations, and reducing the emissions of non-CO2 greenhouse gases (SF6, HFC, and PFC) through the introduction of detoxifying equipment.

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Initiatives Contributing to the Environment and Society

Low Power Consumption Power Devices

Climate change

SiC-SBD power semiconductor

Power devices have been developed and produced using silicon semiconductors. However, they are believed to be approaching a "silicon limit," where it will be impossible to simultaneously achieve an advanced degree of both low loss and high voltage. We are therefore developing semiconductor devices using silicon carbide (SiC), which offers low-power consumption capabilities and can be used in a wide range of applications.

In fiscal 2011, Mitsubishi Electric was the first in the world to equip air conditioners with SiC power modules. Since then, we have promoted their use in various products such as rolling stock and industrial equipment. In fiscal 2016, a full-SiC power module was used in a rolling stock inverter for the first time. In addition, in August 2016, we launched a super-mini full-SiC power module which achieves about 70% reduction*1 in power loss compared to our conventional products, as well as industry-leading low power consumption*2, contributing to reduced energy consumption by air conditioners.

In March 2017, we launched the silicon-carbide Schottky-barrier diode (SiC-SBD*3), which contributes to the reduced the power loss and physical size of power supply systems for photovoltaic power systems, air conditioners and more. This product reduces power loss by about 21%*4 compared to our conventional products.

We will continue to accelerate the development of new technologies and products to respond to market needs.

*1
Compared to super mini DIPIPM Ver.6 series (Si product) PSS15S92F6 (15A/600V).
*2
As of August 17, 2016.
*3
SBD (Schottky Barrier Diode): Diode which utilizes the Schottky barrier formed at the junction of a semiconductor and a metal.
*4
Compared to the Si diode installed in our DIPPFC™ power semiconductor module.

Development of 100Gbps*5 Compact Integrated EML*6 TOSA*7 Optical Transceiver for High Speed Communication

Climate change

100Gbps compact integrated EML TOSA

Energy saving in IT has become a global social issue due to the accelerated speed and capacity of mobile communication networks. It has become necessary to increase the amount of optical transmission equipment in optical fiber communication base stations in order to process the rapidly increasing communication data at a high speed. However, since the space available for the installation of equipment is limited, there is increasing demand for smaller sized and longer distance transmitting optical transceivers in optical transmission equipment. In response to these needs, we have developed the compact integrated 100Gbps EML-TOSA, which has achieved the industry's longest*8 transmission distance of 40km, and significantly reduced package size. We started providing samples in July 2016. We will continue to contribute to the improved performance of equipment in the field of high speed optical communications, a field in which we are expecting a significant increase in demand.

*5
Gbps (Gigabits per second): Unit of communication rate. 1Gbps indicates that 1 billion digital codes can be transmitted per second.
*6
EML (Electro-absorption Modulated Laser diode)
*7
TOSA (Transmitter Optical Sub Assembly): Compact optical device for transmission.
*8
Research by Mitsubishi Electric, as of March 16, 2016. In the IEEE 100GBASE-ER4 standard (100Gbps Ethernet standard set by the US Institute of Electrical and Electronics Engineers).
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Initiatives for Reducing Environmental Impact

Making Cleanrooms More Energy Efficient

Climate change

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 ConditionersClimate change

    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 SystemsClimate change

    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 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.
  • Application of Yellow LED LampsClimate change

    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.

Focusing on Reducing Energy Consumption in Office Buildings by Combining Our Best Energy-Saving Technologies

Climate change

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.

Focusing on Water Recycling and Preventing Contamination from Wastewater

Appropriate use of water in operating areas

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.

Thorough Management of Chemical Substances

Proper management of chemical substances in design and manufacturing

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.

Promotion of Activities for the Conservation of Biodiversity

Conservation of biodiversity in operating areas

We started a biological research project at our Power Device Works and High Frequency & Optical Device Works in fiscal 2016. As a result of examining the creatures and plants living on these sites with expert guidance, we were able to confirm the presence of many regional endemic species, including some designated as endangered species. To encourage the preservation of these local species, we will establish an environment that makes it easier for living things to thrive.

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