Establishment of the Next-Generation Power Devices Research and Development Partnership
- Targeted at the First Application of the Amended Act on Research and Development Partnership concerning Mining and Manufacturing Technology -

1)GaN Power Devices Contribute to Energy-Saving and the Environment

Recently, gallium nitride (GaN) and silicon carbide (SiC) are attracting attention as a new material to replace silicon (Si), which presently constitutes the mainstream of power devices but is apparently reaching its energy loss limit.

SiC is, although it has already entered into the market as a Schottky barrier diode (SBD ^{(Note 1)}), struggling with high costs including those resulting from insufficient substrate sizes.

Alternatively, the GaN power device still remains in the stage of research and development, although it is a major candidate for post-IGBT (insulated gate bipolar transistor) taking advantage of its strong possibility as a high-breakdown voltage, low-loss, high-speed switching device.

On the other hand, the device technology has significantly advanced recently in terms of crystalline defects reduction and device performance improvement, so that it probably becomes possible in a couple of years to supply prototypes that can be used for high-efficiency power circuits that are built in switching power supplies. Early supply of such prototypes will no doubt make a significant contribution to the advancement of power electronics, making a major step forward to productization of GaN power devices.

2)Core Technologies of the Two Companies Are Utilized to Accelerate the Development of Next-Generation Products

Figure 1 Processed epitaxial wafer. (by Furukawa Electric)

Figure 2 Power devices. (by Fuji Electric)

Furukawa Electric has been conducting research and development of GaN-based transistors and diodes, achieving many world-leading results in the field of GaN power devices. See Figure 1.

Meanwhile, Fuji Electric Advanced Technology is the R&D company of Fuji Electric, and has advanced core technologies covering the development and engineering of power devices (See Figure 2) through research and development of application products such as inverters and power supplies. Also the Company has a lot of researchers and engineers that are involved in the design and processing of various devices.

The combination of the two companies to reinforce the mutual strength will surely achieve not only acceleration of the development of practical power devices, but also sharing the burden of funds, making it possible to construct a large-scale R&D organization and to speed up the development time. See Figure 3.

Figure 3 Strong points and synergies of the two companies.

3)Toward the First Application of Amended Act on Research and Development Partnership concerning Mining and Manufacturing Technology

The system of the Research and Development Partnership concerning Mining and Manufacturing Technology that started in 1961 has been extensively utilized as a corporation system for joint research and development among private enterprises, whereby efficient use of R&D resources has been promoted.

What the Amended Act issued on April 30 this year allows is that, in contrast to the former law, it becomes possible to change an R&D partnership into a company structurally in order to commercialize R&D achievements, and that an application for grant can be submitted through agreement between two companies, thus making the application procedure simple and speedy. This background information has made us submit the application form aimed at the first application of the Amended Act on Research and Development Partnership concerning Mining and Manufacturing Technology.

1)Development of Epitaxial Growth Technology

Development of high-quality GaN crystal growth technology on Si substrates enabling cost reduction is carried out for practical realization of SBDs and MOSFETs. Specifically, the epitaxial crystal growth ^{(Note 2)} technology is used to control the deposition conditions of the buffer layer on the Si substrate, thereby achieving quality improvements in terms of reductions in crystal defects and stress.

2)Development of SBD and MOSFET Devices

Development of device structures and process technologies is carried out in order to realize low-loss, switching-applicable SBDs and low-cost MOSFETs. Together with the study on device structures, investigation on mounting structures and reliability evaluation are performed from the standpoint of power device mounting. Though these studies, structure-optimized samples (design samples) and engineering samples are fabricated, to receive public evaluations.

3)Investigation of Business Embarkation

Based on the features of GaN-based SBDs and MOSFETs as semiconductor power devices, promising application fields over existing Si devices and SiC devices are investigated and identified. Moreover, device specifications and desired costs in each application field are clearly determined, in order to include the results into the developmental goals of the devices, and to make proposals to indicate what business expansions should be sought.