3d semiconductor device with isolation layers

A 3D semiconductor device, the device comprising:

• a first level comprising single crystal first transistors, and a first metal layer, and a second metal layer,
• wherein said first level is overlaid by a first isolation layer;
• a second level comprising second transistors,
• wherein said first isolation layer is overlaid by said second level, and
• wherein said second level is overlaid by a second isolation layer;
• a third level comprising single crystal third transistors,
• wherein said second isolation layer is overlaid by said third level,
• wherein said third level is overlaid by a third isolation layer;
• and
• a connective path from said third transistors to said second transistors,
• wherein said connective path comprises a via through said second isolation layer,
• wherein said third level is bonded to said second isolation layer, and
• wherein said bonded comprises at least one oxide to oxide bond.

A 3D semiconductor device, the device comprising:

• a first level comprising single crystal first transistors and plurality of interconnecting metal layers,
• wherein said first level is overlaid by a first isolation layer;
• a second level comprising single crystal second transistors,
• wherein said first isolation layer is overlaid by said second level, and
• wherein said second level is overlaid by a second isolation layer;
• a third level comprising third transistors,
• wherein said second isolation layer is overlaid by said third level,
• wherein said third level is overlaid by a third isolation layer;
• and
• a connective path from said third transistors to said second transistors,
• wherein said connective path comprises a via through said second isolation layer,
• wherein said third level is bonded to said second isolation layer, and
• wherein said bonded comprises at least one oxide to oxide bond.