A 3D semiconductor device, the device including: a first level including a first single crystal layer, the first level including first transistors, where the first transistors each include a single crystal channel; first metal layers interconnecting at least the first transistors; and a second level including a second single crystal layer, the second level including second transistors, where the second level overlays the first level, where the second level is bonded to the first level, where the bonded includes oxide to oxide bonds, where the bonded includes metal to metal bonds, where the second level includes an array of memory cells, and where each of the memory cells includes at least one recessed-channel-array-transistor (RCAT).

A 3D semiconductor device, the device including: a first level including a first single crystal layer, the first level including first transistors, where the first transistors each include a single crystal channel; first metal layers interconnecting at least the first transistors; a second level including a second single crystal layer, the second level including second transistors; and a third level including a third single crystal layer, the third level including third transistors, where the second level overlays the first level, where the second level is bonded to the first level, where the third level is bonded to the second level, where the bonded includes oxide to oxide bonds, where the bonded includes metal to metal bonds, where the second level includes a first array of first memory cells, and where the third level includes a second array of second memory cells.

A 3D device including: a first level including first single crystal transistors overlaid by a second level including second single crystal transistors; a third level including third single crystal transistors, the second level is overlaid by the third level; a fourth level including fourth single crystal transistors, the third level is overlaid by the fourth level; first bond regions including first oxide to oxide bonds, where the first bond regions are between the first level and the second level; second bond regions including second oxide to oxide bonds, where the second bond regions are between the second level and the third level; and third bond regions including third oxide to oxide bonds, where the third bond regions are between the third level and the fourth level, where the second level, third level, and fourth level each include one array of memory cells, and where the one array of memory cells is a DRAM type memory.

A method for producing a 3D memory device, the method including: providing a first level including a first single crystal layer; forming first alignment marks and control circuits including first single crystal transistors; forming at least one second level above the first level; performing a first etch step including etching first holes within the second level; forming at least one third level above the at least one second level; performing a second etch step including etching second holes within the third level; and performing additional processing steps to form a plurality of first memory cells within the second level and a plurality of second memory cells within the third level, where the etching first holes includes performing a lithography step aligned to the first alignment marks.

A 3D semiconductor device, the device including: a first level including single crystal first transistors, and a first metal layer, where the first level is overlaid by a first isolation layer; a second level including second transistors, where the first isolation layer is overlaid by the second level, and where the second level is overlaid by a second isolation layer; a third level including single crystal third transistors, where the second isolation layer is overlaid by the third level, where the third level is overlaid by a third isolation layer, where the third level is bonded to the second isolation layer, where the bonded includes at least one oxide to oxide bond, and where the bonded includes at least one metal to metal bond.

A method for producing a 3D memory device, the method including: providing a first level including a first single crystal layer; forming first alignment marks and control circuits including first single crystal transistors; forming at least one second level above the first level; performing a first etch step including etching first holes within the second level; forming at least one third level above the at least one second level; performing a second etch step including etching second holes within the third level; and performing additional processing steps to form a plurality of first memory cells within the second level and a plurality of second memory cells within the third level, where the etching first holes includes performing a lithography step aligned to the first alignment marks.

A 3D semiconductor device, the device including: a first level including a first single crystal layer and first single crystal transistors; a first metal layer interconnecting the first single crystal transistors; second transistors disposed atop of the first single crystal transistors; third transistors disposed atop of the second transistors; fourth transistors disposed atop of the third transistors; where the fourth transistors include replacement gates, being processed to replace a non-metal gate material with a metal based gate, and where a distance from at least one of the fourth transistors to at least one of the second transistors is less than 1 micron.

A method for producing a 3D memory device, the method including: providing a first level including a first single crystal layer and control circuits; forming at least one second level above the first level; performing a first etch step including etching holes within the second level; forming at least one third level above the at least one second level; performing a second etch step including etching holes within the third level; and performing additional processing steps to form a plurality of first memory cells within the second level and a plurality of second memory cells within the third level, where each of the first memory cells include one first transistor, where each of the second memory cells include one second transistor, where at least one of the first or second transistors has a channel, a source, and a drain having a same doping type.

A 3D semiconductor device, the device comprising: a first level comprising a single crystal layer, first transistors and a first metal layer; memory control circuits comprising said first transistors; a second level disposed above said first level, said second level comprising second transistors; a third level disposed above said second level, said third level comprising a plurality of third transistors; wherein said third transistors are aligned to said first transistors with a less than 40 nm alignment error, wherein said second level comprises a plurality of first memory cells, wherein said third level comprises a plurality of second memory cells, wherein one of said second transistors is at least partially self-aligned to at least one of said third transistors, being processed following a same lithography step, wherein at least one of said second memory cells comprises at least one of said third transistors, wherein said memory cells comprise a NAND non-volatile memory type.

A method of forming contacts to an embedded semiconductor die includes embedding a semiconductor die in an encapsulation material, the semiconductor die having a first terminal at a first side of the semiconductor die, forming a first metal mask on a first surface of the encapsulation material, the first metal mask being positioned over the first side of the semiconductor die and exposing a first part of the encapsulation material aligned with the first terminal of the semiconductor die, directing a pressurized stream of liquid toward the first surface of the encapsulation material with the first metal mask, to remove the first exposed part of the encapsulation material and form a first contact opening to the first terminal of the semiconductor die, and forming an electrically conductive material in the first contact opening. Related semiconductor packages are also described.