A microelectronic device includes a doped region of semiconductor material having a first region and an opposite second region. The microelectronic device is configured to provide a first operational potential at the first region and to provide a second operational potential at the second region. The microelectronic device includes field plate segments in trenches extending into the doped region. Each field plate segment is separated from the semiconductor material by a trench liner of dielectric material. The microelectronic device further includes circuitry electrically connected to each of the field plate segments. The circuitry is configured to apply bias potentials to the field plate segments. The bias potentials are monotonic with respect to distances of the field plate segments from the first region of the doped region.