A driver circuit for a three-dimensional (3D) memory device has a super junction structure as a field management structure. The super junction structure could be referred to as an extended junction structure, which distributes the electrical field of the junction between the vertical channel and the gate conductor for a string driver. The vertical channel includes a channel conductor to connect vertically between a source conductor and a drain conductor. The extended junction structure extends in parallel with the vertical channel conductor, extending vertically toward the drain conductor, having a height greater than a height of the gate conductor.