High Thermal Conductivity Silicon Nitride substrates for Power Semiconductor Applications

The importance of IGBT power modules has been increasing in a variety of applications such as motor control, robotics, traction, power control systems for solar and wind power generations. Especially the rapid spread of hybrid and electric vehicles is supported by the development of power semiconductor devices such as the IGBT. In order to release the heat generated by these power semiconductor devices, insulating substrates with high thermal conductivity are of increasing importance. Recently silicon nitride has attracted much attention as a substrate material for power semiconductor devices because of its excellent mechanical properties and high intrinsic thermal conductivity. Though conventional sintered silicon nitride has excellent mechanical characteristics, its thermal conductivity is limited as high as around 90W/(m K). In order to overcome the limitation, we worked on the development of a silicon nitride substrate with higher thermal conductivity.