3D semiconductor device and structure with metal layers

A semiconductor device, the device comprising:

• a first silicon layer comprising first single crystal silicon;
• a first metal layer over said first silicon layer;
• a second metal layer over said first metal layer;
• a first level comprising a plurality of transistors, said first level over said second metal layer,
• wherein said plurality of transistors comprise second single crystal silicon;
• a third metal layer over said first level;
• a fourth metal layer over said third metal layer,
• wherein said fourth metal layer is aligned to said first metal layer with less than 40 nm alignment error;
• and
• a via disposed through said first level,
• wherein said via comprises tungsten.

A semiconductor device, the device comprising:

• a first silicon layer comprising first single crystal silicon;
• a first metal layer over said first silicon layer;
• a second metal layer over said first metal layer;
• a first level comprising a plurality of transistors, said first level over said second metal layer,
• wherein said plurality of transistors comprise second single crystal silicon;
• a third metal layer over said first level;
• a fourth metal layer over said third metal layer,
• wherein said fourth metal layer is aligned to said first metal layer with less than 40 nm alignment error;
• a global power distribution network and a local power distribution network,
• wherein said global power distribution network comprises said fourth metal layer, and
• wherein said local power distribution network comprises said third metal layer.