Many functions of modern devices in automotive, consumer and industrial applications, such as converting electrical energy and driving an electric motor or an electric machine, rely on power semiconductor devices. For example, Insulated Gate Bipolar Transistors (IGBTs), Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) and diodes, to name a few, have been used for various applications including, but not limited to switches in power supplies and power converters.
A power semiconductor device usually comprises a semiconductor body configured to conduct a load current along a load current path between two load terminals of the device. Further, the load current path may be controlled by means of an insulated control electrode, sometimes referred to as gate electrode. For example, upon receiving a corresponding control signal from, e.g., a driver unit, the control electrode may set the power semiconductor device in one of a conducting state and a blocking state.
Said power semiconductor devices shall usually have low power losses, e.g., low switching losses and/or low on-state losses, such that said application, e.g., said power supplies and power converters, may exhibit a high efficiency. To this end, compensation structures, which are also referred to as superjunction structures or CoolMOS™ structures, have been proposed. For example, superjunction structures can be established in the semiconductor body by means of carrying out one or more epitaxy processing steps.
Beyond low power losses, said power semiconductor devices shall sometimes simultaneously exhibit high blocking capabilities, e.g., up to 1000 Volts and above, and/or shall be designed for high currents, e.g., up to several hundred Amperes.
USPTO Backgrounds
USPTO Backgrounds