Power semiconductor devices are semiconductor devices used as switches or rectifiers in power electronic circuits (switch mode power supplies for example). They are also called power devices or when used in integrated circuits, called power ICs.
Some common power devices are the power diode, thyristor, power MOSFET and IGBT (insulated gate bipolar transistor). A power diode or MOSFET, for example, operates on similar principles as its low-power counterpart, but is able to carry a larger amount of current and typically is able to support a larger reverse-bias voltage in the off-state.
Research needs in this area include on one hand to increase the maximum power handling capability of the power devices, on the other hand include the need to increase the speed they can switch. Power semiconductor is also the key in determining the power conversion efficiency. NCSU's research concentration is on power devices that use wide bandgap semiconductor materials (e.g. SiC and GaN).
Research projects are focused on the analysis of power device structures using numerical simulations and the development of analytical models based on semiconductor transport physics. Students are encouraged to validate the theoretical analysis using electrical characterization of commercially available devices and by the fabrication of novel device structures. The impact of improvements in power device characteristics on specific applications allows an understanding of trade-offs between on-state characteristics, reverse blocking capability, and switching performance.