Expanding production capacity of gallium nitride epitaxial wafers that support the age of ubiquitous networks

GaN epitaxial wafer, a key element supporting the age of ubiquitous networks

 High-performance electronic devices, such as power amplifiers, capable of operating at high frequencies are indispensable for building the super-high-speed, high-capacity wireless communication systems that will be essential in the coming age of ubiquitous networks, which will allow people to be connected to a network anytime and anywhere. It is imperative to continue reducing the size and power consumption of electronic systems. As a new device that fulfills these requirements, GaN electronic devices are attracting attention because they can be used as voltage converters that are able to operate at low power in a high-temperature environment. There is now a strong demand to build the capability that can ensure the stable supply of GaN epitaxial wafers, which will become a key element for fabricating GaN electronic devices in the future.

Mass production capability established based on NTT-AT's unique production technology

 In light of the strong demand mentioned above, NTT-AT customized GaN epitaxial wafers to suit customers' needs based on the basic technology developed by NTT Laboratories, and started production and sales in 2005. This has contributed to the progress in GaN electronic devices. NTT-AT has now decided to subcontract the production of the wafers to Mitsubishi Chemical in order to ensure mass production on a scale sufficient to allow a rapid response to the predicted expansion of the market. The technology for the mass production of GaN epitaxial wafers for LEDs using MOCVD^*2 (developed over a number of years by Mitsubishi Chemical) is now integrated with the production know-how of NTT-AT to establish the capability for mass production of GaN epitaxial wafers for use in electronic devices. This will provide the impetus for further development of high-performance GaN electronic devices.

GaN also adopted in the base substrate to achieve higher performance

 To further boost the performance of GaN electronic devices, the two companies are undertaking joint R&D so that a new type of GaN epitaxial wafer that uses GaN as the base substrate can be incorporated into electronic devices. Mitsubishi Chemical has been producing and selling this type of wafer for use in white LEDs.

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Glossary

*1:Gallium nitride epitaxial wafer

 A thin film of gallium nitride crystal grown on a base substrate made of silicon (Si), sapphire (Al₂O₃), etc. It is used as a material for a power switching element used in power amplifiers or inverters (power circuits) for mobile communication base stations.

*2:MOCVD(Metal Organic Chemical Vapor Deposition)

 A way of growing a semiconductor crystal by depositing metal organic chemical vapor.

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[About NTT Advanced Technology Corporation]

Established	December 17 1976
Head office	Shinjuku Mitsui Bldg., 2-1-1, Nishi-shinjuku, Shinjuku-ku, Tokyo, 163-0431, Japan
Capital	5 billion yen
Shareholders	Nippon Telegraph and Telephone Corporation (NTT)
Business activities	Infrastructure system business, Solution system business, Product sales system business

[About Mitsubishi Chemical Corporation]

Incorporation	October 1, 1994 (Establishment: June 1, 1950)
Head office	14-1 Shiba 4-chome, Minato-ku, Tokyo 108-0014, Japan
Capital	50,000 million yen
Shareholders	Mitsubishi Chemical Holdings Corporation
Business activities	Performance products, Health care, Chemcials, and Others