A 3D semiconductor device, the device including: a first level including single crystal first transistors, a first metal layer, and a first isolation layer; a second level including second transistors and a second isolation layer, where the first level is overlaid by the second level; a third level including single crystal third transistors, where the second level is overlaid by the third level, where the third level includes a third isolation layer, and where the third level is bonded to the second level; a power delivery path to the second transistors, where at least a portion of the power delivery path is connected to at least one of the first transistors; and a plurality of capacitors, where the single crystal first transistors or the second transistors include at least two FinFet transistors, and where two of the at least two FinFet transistors have different threshold voltages (Vt).