A semiconductor structure for a microelectromechanical systems (MEMS) device is provided. A first substrate region includes an electrical isolation layer arranged over a top surface of the first substrate region. A second substrate region is arranged over the electrical isolation layer and includes a MEMS device structure arranged within the second substrate region. The MEMS device structure includes a fixed mass and a proof mass. A dielectric region is arranged over the electrical isolation layer around the fixed mass. A fixed mass electrode is arranged around the dielectric region, and extends through the second substrate region to the electrical isolation layer. An isolated electrode extends through the second substrate region and the electrical isolation layer to the first substrate region on an opposite side of the proof mass as the fixed mass electrode. The method of forming the semiconductor structure is also provided.