Showa Denko K.K. (SDK) has increased its four-inch silicon carbide (SiC) epitaxial wafer production capacity by 2.5 times, to 1,500 units a month, through facility expansion and improvement in production technology.  These wafers, with high surface smoothness and low crystal defect, are being produced at SDK’s Chichibu Plant in Saitama Prefecture.

When compared with the mainstream silicon-based semiconductors, SiC power devices using SiC epitaxial wafers can operate under high-voltage heavy current and at high temperatures.  These features enable reductions in the number of components and miniaturization of cooling devices, helping to make smaller and lighter power control modules.  SiC power devices also reduce energy loss in the process of power control, resulting in a substantial energy saving.

Thus, SiC power devices will find a wide range of applications, including automobiles, railcars, and industrial/home electric appliances.  In particular, SiC power devices are expected to be used increasingly in inverters (devices for converting direct current into alternating current) to control rotation of motors.  Such inverters are already commercialized in some home electric appliances and distributed power supply systems, and used in subway railcars on a trial basis.  Furthermore, an increasing number of electric vehicles and hybrid cars are expected to be equipped with inverters using SiC power devices.

These inverters contain Schottky barrier diode (SBD), and metal oxide semiconductor field-effect transistor (MOSFET), based on SiC power devices.  SiC-MOSFET requires high surface smoothness as it uses oxide film formed on the surface of epitaxial wafers in device operation.  SDK’s SiC epitaxial wafers, having high surface smoothness, are valued highly for use in high-quality SiC-MOSFET.

Following the capacity expansion, SDK will continue developing SiC epitaxial wafers with larger diameter, lower defect, and higher uniformity.  Specifically, SDK will accelerate the development of six-inch SiC epitaxial wafers for heavy-current high-voltage applications.

[Reference]

(1)Appearance of SiC epitaxial wafers

(2)Conceptual drawings of SBD and MOSFET, based on SiC epitaxial wafers

(3) Outline of products related to SiC epitaxial wafers

Showa Denko K.K.:
IR & PR Office (Phone: 81-3-5470-3235)