Trends in the design and technology of power semiconductor devices are discussed on the threshold of the year 2015. Well established silicon technologies continue to occupy the most of applications thanks to the maturity of switches like MOSFET, IGBT, IGCT and PCT. Silicon carbide (SiC) and gallium nitride (GaN) are striving to take over that of the silicon. The most relevant SiC device is the MPS (JBS) diode, followed by MOSFET and JFET. GaN devices are represented by lateral HEMT. While the long term reliability of silicon devices is well trusted, the SiC MOSFETs and GaN HEMTs are struggling to achieve a similar confidence. Two order higher cost of SiC equivalent functional performance at device level limits their application to specific cases, but their number is growing. Next five years will therefore see the co-existence of these technologies. Silicon will continue to occupy the most of applications and dominate the high-power sector. The wide bandgap devices will expand mainly in the 600 - 1200 V range and dominate the research regardless of the voltage class
