Patent ID: 9406755
Filing Date: 2016-08-02
CPC Classification: H01L

Claim Text:
1. A semiconductor device comprising: a semiconductor substrate doped with dopants of a first type; a vertical transistor composed of one or more transistor cells, each transistor cell having a body region formed in the substrate and doped with dopants of a second type, the body regions forming first pn-junctions with the surrounding substrate; at least a first well region formed in the substrate and doped with dopants of a second type to form a second pn-junction with the substrate, the first well region being electrically connected to the body regions of the vertical transistor via a semiconductor switch; a second well region formed in the substrate and doped with dopants of a second type to form a third pn-junction with the substrate; and a detection circuit at least partially integrated in the second well region which detects whether the first pn-junctions are reverse biased, wherein the semiconductor switch electrically connects or disconnects the first well region(s) and the body regions of the transistor cells based on whether the first pn-junctions are reverse biased or not reverse biased, wherein the switch is driven to be opened when the first pn-junctions are reverse biased, and to be closed when the first pn-junctions are not reverse biased.