A semiconductor device includes a guard structure located laterally between a first active area of a semiconductor substrate and a second active area of the semiconductor substrate. The guard structure includes a first doping region located at a front side surface of the semiconductor substrate, and a wiring structure electrically connecting the first doping region to a highly doped portion of a common doping region. The common doping region extends from a backside surface of the semiconductor substrate to at least a part of the front side surface of the semiconductor substrate in contact with the wiring structure of the guard structure. Corresponding methods for forming the semiconductor device are also described.