A 3D semiconductor device including: a first level including a first single crystal layer and first transistors, and at least one first metal layer-which includes interconnects between the first transistors forming control circuits-which overlays the first single crystal layer; a second metal layer overlaying first metal layer; a second level including second transistors, first memory cells (each including at least one second transistor) and overlaying second metal layer; a third level including third transistors (at least one includes a polysilicon channel), second memory cells (each including at least one third transistor and cell is partially disposed atop control circuits) and overlaying the second level; control circuits control data written to second memory cells; third metal layer disposed above third level; fourth metal layer includes a global power distribution grid, has a thickness at least twice the second metal layer, and is disposed above third metal layer.