Embodiments of 3D memory devices and methods for forming the same are disclosed. In an example, a 3D memory device includes a substrate, a peripheral circuit on the substrate, a memory stack including interleaved conductive layers and dielectric layers above the peripheral circuit, a first semiconductor layer above the memory stack, a second semiconductor layer above and in contact with the first semiconductor layer, a plurality of channel structures each extending vertically through the memory stack and the first semiconductor layer, and a source contact above the memory stack and in contact with the second semiconductor layer.

A semiconductor device includes a first die, a second die on the first die, and a third die on the second die, the second die being interposed between the first die and the third die. The first die includes a first substrate and a first interconnect structure on an active side of the first substrate. The second die includes a second substrate, a second interconnect structure on a backside of the second substrate, and a power distribution network (PDN) structure on the second interconnect structure such that the second interconnect structure is interposed between the PDN structure and the second substrate.

In one embodiment, an integrated device package is disclosed. The integrated device package can comprise a carrier an a molding compound over a portion of an upper surface of the carrier. The integrated device package can comprise an integrated device die mounted to the carrier and at least partially embedded in the molding compound, the integrated device die comprising active circuitry. The integrated device package can comprise a stress compensation element mounted to the carrier and at least partially embedded in the molding compound, the stress compensation element spaced apart from the integrated device die, the stress compensation element comprising a dummy stress compensation element devoid of active circuitry. At least one of the stress compensation element and the integrated device die can be directly bonded to the carrier without an adhesive.

A first wafer, a method of fabricating thereof and a wafer stack are disclosed. The first wafer includes a first substrate, a first dielectric layer on the first substrate, first metal layers embedded in the first dielectric layer, first switching holes extending partially through the first dielectric layer and exposing the first metal layers, a first interconnection layer filling up the first switching holes and electrically connected to the first metal layers, a first insulating layer residing on surfaces of both the first dielectric layer and the first interconnection layer, first contact holes extending through the first insulating layer and exposing the first interconnection layer, and a second interconnection layer filling up the first contact holes and electrically connected to the first interconnection layer. Filling the first contact holes and the first switching holes with different interconnection layers reduces the difficulty in fabricating interconnection structures for the first metal layers.

Embodiments of bonded semiconductor structures and fabrication methods thereof are disclosed. In an example, a semiconductor device includes a first and a second semiconductor structures. The first semiconductor structure includes a first interconnect layer including first interconnects. At least one first interconnect is a first dummy interconnect. The first semiconductor structure further includes a first bonding layer including first bonding contacts. Each first interconnect is in contact with a respective first bonding contact. The second semiconductor structure includes a second interconnect layer including second interconnects. At least one second interconnect is a second dummy interconnect. The second semiconductor structure further includes a second bonding layer including second bonding contacts. Each second interconnect is in contact with a respective second bonding contact. The semiconductor device further includes a bonding interface between the first and second bonding layers. Each first bonding contact is in contact with a respective second bonding contact at the bonding interface.

A method of routing electrical connections in a wafer-on-wafer structure comprises, bonding a metal bonding pad of a first wafer to a metal bonding pad of a second wafer; bonding first wafer to the second wafer with a material different from the metal bonding pads; forming metal interconnect structures connecting the metal bonding pad of the first wafer to a first device disposed within a first and second side of the first wafer; and forming metal interconnect structures connecting the metal bonding pad of the second wafer to a second and third devices disposed within the second wafer, to connect the first device to the second and third devices through the metal bonding pads, wherein the electrical connections of the devices between the first and second wafers do not have a through-via that passes completely through the first or the second wafer.

A memory device includes a cell wafer including a memory cell array; a first logic wafer bonded to one surface of the cell wafer, and including a first logic circuit which controls the memory cell array; and a second logic wafer bonded to the other surface of the cell wafer which faces away from the one surface, and including a second logic circuit which controls the memory cell array.

A memory device includes a first memory block defined in a first wafer; and a second memory block defined in a second wafer that is disposed in a vertical direction with respect to the first wafer. A size of the first memory block is smaller than a size of the second memory block.

A package structure includes a first die, a die stack structure, a support structure and an insulation structure. The die stack structure is bonded to the first die. The support structure is disposed on the die stack structure. A width of the support structure is larger than a width of the die stack structure and less than a width of the first die. The insulation structure at least laterally wraps around the die stack structure and the support structure.

Multiple bonded units are provided, each of which includes a respective front-side die and a backside die. The two dies in each bonded unit may be a memory die and a logic die configured to control operation of memory elements in the memory die. Alternatively, the two dies may be memory dies. The multiple bonded units can be attached such that front-side external bonding pads have physically exposed surfaces that face upward and backside external bonding pads of each bonded unit have physically exposed surfaces that face downward. A first set of bonding wires can connect a respective pair of front-side external bonding pads, and a second set of bonding wires can connect a respective pair of backside external bonding pads.