The present invention discloses a discrete three-dimensional vertical memory (3D-MV). It comprises at least a 3D-array die and at least a peripheral-circuit die. The 3D-array die comprises a plurality of vertical memory strings. At least an off-die peripheral-circuit component of the 3D-MV arrays is located on the peripheral-circuit die instead of the 3D-array die. The 3D-array die and the peripheral-circuit die have substantially different back-end-of-line (BEOL) structures.