A method of making an assembly can include juxtaposing a top surface of a first electrically conductive element at a first surface of a first substrate with a top surface of a second electrically conductive element at a major surface of a second substrate. One of: the top surface of the first conductive element can be recessed below the first surface, or the top surface of the second conductive element can be recessed below the major surface. Electrically conductive nanoparticles can be disposed between the top surfaces of the first and second conductive elements. The conductive nanoparticles can have long dimensions smaller than 100 nanometers. The method can also include elevating a temperature at least at interfaces of the juxtaposed first and second conductive elements to a joining temperature at which the conductive nanoparticles can cause metallurgical joints to form between the juxtaposed first and second conductive elements.

An apparatus according to the present invention in which a first substrate including a photoelectric conversion element and a gate electrode of a transistor, and a second substrate including a peripheral circuit portion are placed upon each other. The first substrate does not include a high-melting-metal compound layer, and the second substrate includes a high-melting-metal compound layer.

Layer structures for making direct metal-to-metal bonds at low temperatures and shorter annealing durations in microelectronics are provided. Example bonding interface structures enable direct metal-to-metal bonding of interconnects at low annealing temperatures of 150° C. or below, and at a lower energy budget. The example structures provide a precise metal recess distance for conductive pads and vias being bonded that can be achieved in high volume manufacturing. The example structures provide a vertical stack of conductive layers under the bonding interface, with geometries and thermal expansion features designed to vertically expand the stack at lower temperatures over the precise recess distance to make the direct metal-to-metal bonds. Further enhancements, such as surface nanotexture and copper crystal plane selection, can further actuate the direct metal-to-metal bonding at lowered annealing temperatures and shorter annealing durations.

A semiconductor package includes a first connection structure, a first semiconductor chip on an upper surface of the first connection structure, a first molding layer on the upper surface of the first connection structure and surrounding the first semiconductor chip, a first bond pad on the first semiconductor chip, a first bond insulation layer on the first semiconductor chip and the first molding layer and surrounding the first bond pad, a second bond pad directly contacting the first bond pad, a second bond insulation layer surrounding the second bond pad; and a second semiconductor chip on the second bond pad and the second bond insulation layer.

A member for a solid-state image pickup device having a bonding plane with no gaps and a method for manufacturing the same are provided. The manufacturing method includes the steps of providing a first substrate provided with a photoelectric converter on its primary face and a first wiring structure, providing a second substrate provided with a part of a peripheral circuit on its primary face and a second wiring structure, and performing bonding so that the first substrate, the first wiring structure, the second wiring structure, and the second substrate are disposed in this order. In addition, at least one of an upper face of the first wiring structure and an upper face of the second wiring structure has a concave portion, and a conductive material forms a bottom face of the concave portion.

A bonded assembly includes a first semiconductor die that includes first metallic bonding structures embedded within a first bonding-level dielectric layer, and a second semiconductor die that includes second metallic bonding structures embedded within a second bonding-level dielectric layer and bonded to the first metallic bonding structures by metal-to-metal bonding. One of the first metallic bonding structures a pad portion, and a via portion located between the pad portion and the first semiconductor device, the via portion having second tapered sidewalls.

A first metal layer can be deposited over first dielectric material layers of a first substrate, and can be patterned into first bonding pads. A first low-k material layer can be formed over the first bonding pads. The first low-k material layer includes a low-k dielectric material such as a MOF dielectric material or organosilicate glass. A second semiconductor die including second bonding pads can be provided. The first bonding pads are bonded to the second bonding pads to form a bonded assembly.

A wafer-to-wafer bonding structure includes a first wafer including a first conductive pad in a first insulating layer and a first barrier layer surrounding a lower surface and side surfaces of the first conductive pad, a second wafer including a second conductive pad in a second insulating layer and a second barrier layer surrounding a lower surface and side surfaces of the second conductive pad, the second insulating layer being bonded to the first insulating layer, and at least a portion of an upper surface of the second conductive pad being partially or entirely bonded to at least a portion of an upper surface of the first conductive pad, and a third barrier layer between portions of the first and second wafers where the first and second conductive pads are not bonded to each other.

A representative device includes a patterned opening through a layer at a surface of a device die. A liner is disposed on sidewalls of the opening and the device die is patterned to extend the opening further into the device die. After patterning, the liner is removed. A conductive pad is formed in the device die by filling the opening with a conductive material.

Structures and techniques provide bond enhancement in microelectronics by trapping contaminants and byproducts during bonding processes, and arresting cracks. Example bonding surfaces are provided with recesses, sinks, traps, or cavities to capture small particles and gaseous byproducts of bonding that would otherwise create detrimental voids between microscale surfaces being joined, and to arrest cracks. Such random voids would compromise bond integrity and electrical conductivity of interconnects being bonded. In example systems, a predesigned recess space or predesigned pattern of recesses placed in the bonding interface captures particles and gases, reducing the formation of random voids, thereby improving and protecting the bond as it forms. The recess space or pattern of recesses may be placed where particles collect on the bonding surface, through example methods of determining where mobilized particles move during bond wave propagation. A recess may be repeated in a stepped reticule pattern at the wafer level, for example, or placed by an aligner or alignment process.