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.

A method for attaching a semiconductor die to a substrate includes providing a substrate that includes an attachment layer at a surface of the substrate. The attachment layer is covered by a protective flash plating layer. The protective flash plating layer has a reflow temperature less than or equal to a reflow temperature of the attachment layer. The method further includes preheating the substrate to a temperature greater than or equal to a reflow temperature of the attachment layer, attaching a semiconductor die to the attachment layer, and cooling the substrate and semiconductor die.

A package includes a semiconductor carrier, a first die, a second die, a first encapsulant, a second encapsulant, and an electron transmission path. The first die is disposed over the semiconductor carrier. The second die is stacked on the first die. The first encapsulant laterally encapsulates the first die. The second encapsulant laterally encapsulates the second die. The electron transmission path is electrically connected to a ground voltage. A first portion of the electron transmission path is embedded in the semiconductor carrier, a second portion of the electron transmission path is aside the first die and penetrates through the first encapsulant, and a third portion of the electron transmission path is aside the second die and penetrates through the second encapsulant.

At least one polymer material may be employed to facilitate bonding between the semiconductor dies. Plasma treatment, formation of a blended polymer, or formation of polymer hairs may be employed to enhance bonding. Alternatively, air gaps can be formed by subsequently removing the polymer material to reduce capacitive coupling between adjacent bonding pads.

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 an insulating structure extending vertically through the memory stack, the first semiconductor layer, and the second semiconductor layer.

First and second contacts are formed on first and second wafers from disparate first and second conductive materials, at least one of which is subject to surface oxidation when exposed to air. A layer of oxide-inhibiting material is disposed over a bonding surface of the first contact and the first and second wafers are positioned relative to one another such that a bonding surface of the second contact is in physical contact with the layer of oxide-inhibiting material. Thereafter, the first and second contacts and the layer of oxide-inhibiting material are heated to a temperature that renders the first and second contacts and the layer of oxide-inhibiting material to liquid phases such that at least the first and second contacts alloy into a eutectic bond.

A method includes putting a first package component into contact with a second package component. The first package component comprises a first dielectric layer including a first dielectric material, and the first dielectric material is a silicon-oxide-based dielectric material. The second package component includes a second dielectric layer including a second dielectric material different from the first dielectric material. The second dielectric material comprises silicon and an element selected from the group consisting of carbon, nitrogen, and combinations thereof. An annealing process is performed to bond the first dielectric layer to the second dielectric layer.

A method of manufacturing a semiconductor device includes forming a cell chip including a first substrate, a source layer on the first substrate, a stacked structure on the source layer, and a channel layer passing through the stacked structure and coupled to the source layer, flipping the cell chip, exposing a rear surface of the source layer by removing the first substrate from the cell chip, performing surface treatment on the rear surface of the source layer to reduce a resistance of the source layer, forming a peripheral circuit chip including a second substrate and a circuit on the second substrate, and bonding the cell chip including the source layer with a reduced resistance to the peripheral circuit chip.

Embodiments of bonded unified semiconductor chips and fabrication and operation methods thereof are disclosed. In an example, a method for forming a unified semiconductor chip is disclosed. A first semiconductor structure is formed. The first semiconductor structure includes one or more processors, an array of embedded DRAM cells, and a first bonding layer including a plurality of first bonding contacts. A second semiconductor structure is formed. The second semiconductor structure includes an array of NAND memory cells and a second bonding layer including a plurality of second bonding contacts. The first semiconductor structure and the second semiconductor structure are bonded in a face-to-face manner, such that the first bonding contacts are in contact with the second bonding contacts at a bonding interface.

Embodiments of bonded unified semiconductor chips and fabrication and operation methods thereof are disclosed. In an example, a method for forming a unified semiconductor chip is disclosed. A first semiconductor structure is formed. The first semiconductor structure includes one or more processors, an array of embedded DRAM cells, and a first bonding layer including a plurality of first bonding contacts. A second semiconductor structure is formed. The second semiconductor structure includes an array of NAND memory cells and a second bonding layer including a plurality of second bonding contacts. The first semiconductor structure and the second semiconductor structure are bonded in a face-to-face manner, such that the first bonding contacts are in contact with the second bonding contacts at a bonding interface.