A bonded assembly includes a first semiconductor die containing a first substrate, first semiconductor devices, and first bonding pads laterally surrounded by a first pad-level dielectric layer. The first pad-level dielectric layer includes at least one first encapsulated airgap located between neighboring pairs of first bonding pads and encapsulated by a first dielectric fill material of the first pad-level dielectric layer. The bonded assembly includes a second semiconductor die containing a second substrate, second semiconductor devices, and second bonding pads laterally surrounded by a second pad-level dielectric layer. Each of the second bonding pads is bonded to a respective one of the first bonding pads.

A bonded assembly includes a first semiconductor die containing a first substrate, first semiconductor devices, and first bonding pads laterally surrounded by a first pad-level dielectric layer. The first pad-level dielectric layer includes at least one first encapsulated airgap located between neighboring pairs of first bonding pads and encapsulated by a first dielectric fill material of the first pad-level dielectric layer. The bonded assembly includes a second semiconductor die containing a second substrate, second semiconductor devices, and second bonding pads laterally surrounded by a second pad-level dielectric layer. Each of the second bonding pads is bonded to a respective one of the first bonding pads.

A semiconductor package includes: a first structure having a first insulating layer disposed on one surface, and first electrode pads and first dummy pads penetrating through the first insulating layer, a second structure having a second insulating layer having the other surface bonded to the one surface and the first insulating layer and disposed on the other surface, and second electrode pads and second dummy pads that penetrate through the second insulating layer, the second electrode pads being bonded to the first electrode pads, respectively, and the second dummy pads being bonded to the first dummy pads, respectively. In the semiconductor chip, ratios of surface areas per unit area of the first and second dummy pads to the first and second insulating layers on the one surface and the other surface gradually decrease toward sides of the first and second structures.

A semiconductor package includes: a first structure having a first insulating layer disposed on one surface, and first electrode pads and first dummy pads penetrating through the first insulating layer, a second structure having a second insulating layer having the other surface bonded to the one surface and the first insulating layer and disposed on the other surface, and second electrode pads and second dummy pads that penetrate through the second insulating layer, the second electrode pads being bonded to the first electrode pads, respectively, and the second dummy pads being bonded to the first dummy pads, respectively. In the semiconductor chip, ratios of surface areas per unit area of the first and second dummy pads to the first and second insulating layers on the one surface and the other surface gradually decrease toward sides of the first and second structures.

Forming a 3DIC includes providing a lower device structure comprising a first substrate with a circuit layer, providing an interconnect network layer having an interconnect structure with a first coupled to a second plurality of electrodes by connection structures on a semiconductor substrate, the first plurality of electrodes being exposed on a first surface of the interconnect layer, implanting ions through the interconnect structure to form a cleave plane in the semiconductor substrate, bonding the interconnect structure to the lower device structure so that electrodes of the first plurality of electrodes are coupled to corresponding electrodes on the lower device structure, cleaving the substrate of the bonded interconnect layer at the cleave plane, removing material from the semiconductor substrate until the second plurality of electrodes is exposed, and bonding an upper device layer to the interconnect structure.

Forming a 3DIC includes providing a lower device structure comprising a first substrate with a circuit layer, providing an interconnect network layer having an interconnect structure with a first coupled to a second plurality of electrodes by connection structures on a semiconductor substrate, the first plurality of electrodes being exposed on a first surface of the interconnect layer, implanting ions through the interconnect structure to form a cleave plane in the semiconductor substrate, bonding the interconnect structure to the lower device structure so that electrodes of the first plurality of electrodes are coupled to corresponding electrodes on the lower device structure, cleaving the substrate of the bonded interconnect layer at the cleave plane, removing material from the semiconductor substrate until the second plurality of electrodes is exposed, and bonding an upper device layer to the interconnect structure.

Embodiments of three-dimensional (3D) memory devices with embedded dynamic random-access memory (DRAM) and methods for forming the 3D memory devices are disclosed. In an example, a method for operating a 3D memory device is disclosed. The 3D memory device includes an input/output circuit, an array of embedded DRAM cells, and an array of 3D NAND memory strings in a same chip. Data is transferred through the input/output circuit to the array of embedded DRAM cells. The data is buffered in the array of embedded DRAM cells. The data is stored in the array of 3D NAND memory strings from the array of embedded DRAM cells.

Embodiments of three-dimensional (3D) memory devices with embedded dynamic random-access memory (DRAM) and methods for forming the 3D memory devices are disclosed. In an example, a method for operating a 3D memory device is disclosed. The 3D memory device includes an input/output circuit, an array of embedded DRAM cells, and an array of 3D NAND memory strings in a same chip. Data is transferred through the input/output circuit to the array of embedded DRAM cells. The data is buffered in the array of embedded DRAM cells. The data is stored in the array of 3D NAND memory strings from the array of embedded DRAM cells.

Three-dimensional (3D) memory devices with 3D phase-change memory (PCM) and methods for forming and operating the 3D memory devices are disclosed. In an example, a 3D memory device includes a first semiconductor structure including an array of NAND memory cells, and a first bonding layer including first bonding contacts. The 3D memory device also further includes a second semiconductor structure including a second bonding layer including second bonding contacts, a semiconductor layer and a peripheral circuit and an array of PCM cells between the second bonding layer and the semiconductor layer. The 3D memory device further includes a bonding interface between the first and second bonding layers. The first bonding contacts are in contact with the second bonding contacts at the bonding interface.

Three-dimensional (3D) memory devices with 3D phase-change memory (PCM) and methods for forming and operating the 3D memory devices are disclosed. In an example, a 3D memory device includes a first semiconductor structure including an array of NAND memory cells, and a first bonding layer including first bonding contacts. The 3D memory device also further includes a second semiconductor structure including a second bonding layer including second bonding contacts, a semiconductor layer and a peripheral circuit and an array of PCM cells between the second bonding layer and the semiconductor layer. The 3D memory device further includes a bonding interface between the first and second bonding layers. The first bonding contacts are in contact with the second bonding contacts at the bonding interface.