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 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.
In designing such semiconductor devices, several aspects need to be considered at a time. For example, it is generally desirable to find an optimal balance between a small channel resistance, a small short circuit current, certain targeted injection properties, and a current switch-off capability of an IGBT. Conventionally, this optimization problem is addressed by creating a superposition of several different doping profiles corresponding to, for example, a source region, and anti-latch up zone, and a body region within a MOS control head of a power transistor, such as an IGBT. However, due to interactions between the different doping profiles, it is generally not possible to optimize one profile with respect to properties of the corresponding semiconductor region without affecting adversely the properties of another semiconductor region. For example, an increased dopant level of said source region may yield an undesired increase of an anti-latch up resistance due to interference of the corresponding doping profiles.
USPTO Backgrounds
USPTO Backgrounds