Some embodiments of the present disclosure relate to a memory array comprising memory cells having vertical gate-all-around (GAA) selection transistors. In some embodiments, the memory array has a source region disposed within an upper surface of a semiconductor body, and a semiconductor pillar of semiconductor material extending outward from the upper surface of the semiconductor body and having a channel region and an overlying drain region. A gate region vertically overlies the source region at a position laterally separated from sidewalls of the channel region by a gate dielectric layer. A first metal contact couples the drain region to a data storage element that stores data. The vertical GAA selection transistors provide for good performance, while decreasing the size of the selection transistor relative to a planar MOSFET, so that the selection transistors do not negatively impact the size of the memory array.