Memory arrays and methods of forming the same are provided. An example memory array can include at least one plane having a plurality of memory cells arranged in a matrix and a plurality of plane selection devices. Groups of the plurality of memory cells are communicatively coupled to a respective one of a plurality of plane selection devices. A decode logic having elements is formed in a substrate material and communicatively coupled to the plurality of plane selection devices. The plurality of memory cells and the plurality of plane selection devices are not formed in the substrate material.