Disclosed herein is an electrical connecting structure having nano-twins copper, including a first substrate having a first nano-twins copper layer and a second substrate having a second nano-twins copper layer. The first nano-twins copper layer includes a plurality of first nano-twins copper grains. The second nano-twins copper layer includes a plurality of second nano-twins copper grains. The first nano-twins copper layer is joined with the second nano-twins copper layer. At least a portion of the first nano-twins copper grains extend into the second nano-twins copper layer, or at least a portion of the second nano-twins copper grains extend into the first nano-twins copper layer.

Representative implementations of techniques and methods include chemical mechanical polishing for hybrid bonding. The disclosed methods include depositing and patterning a dielectric layer on a substrate to form openings in the dielectric layer, depositing a barrier layer over the dielectric layer and within a first portion of the openings, and depositing a conductive structure over the barrier layer and within a second portion of the openings not occupied by the barrier layer, at least a portion of the conductive structure in the second portion of the openings coupled or contacting electrical circuitry within the substrate. Additionally, the conductive structure is polished to reveal portions of the barrier layer deposited over the dielectric layer and not in the second portion of the openings. Further, the barrier layer is polished with a selective polish to reveal a bonding surface on or at the dielectric layer.

A copper paste for pressureless bonding is a copper paste for pressureless bonding, containing: metal particles; and a dispersion medium, in which the metal particles include sub-micro copper particles having a volume average particle diameter of greater than or equal to 0.01 μm and less than or equal to 0.8 μm, and micro copper particles having a volume average particle diameter of greater than or equal to 2.0 μm and less than or equal to 50 μm, and the dispersion medium contains a solvent having a boiling point of higher than or equal to 300° C., and a content of the solvent having a boiling point of higher than or equal to 300° C. is greater than or equal to 2 mass % on the basis of a total mass of the copper paste for pressureless bonding.

A copper paste for pressureless bonding is a copper paste for pressureless bonding, containing: metal particles; and a dispersion medium, in which the metal particles include sub-micro copper particles having a volume average particle diameter of greater than or equal to 0.01 μm and less than or equal to 0.8 μm, and micro copper particles having a volume average particle diameter of greater than or equal to 2.0 μm and less than or equal to 50 μm, and the dispersion medium contains a solvent having a boiling point of higher than or equal to 300° C., and a content of the solvent having a boiling point of higher than or equal to 300° C. is greater than or equal to 2 mass % on the basis of a total mass of the copper paste for pressureless bonding.

A bonding structure is provided, wherein the bonding structure includes a first substrate, a second substrate, a first adhesive layer, a second adhesive layer, and a silver feature. The second substrate is disposed opposite to the first substrate. The first adhesive layer is disposed on the first substrate. The second adhesive layer is disposed on the second substrate and opposite the first adhesive layer. The silver feature is disposed between the first adhesive layer and the second adhesive layer. The silver feature includes a silver nano-twinned structure that includes twin boundaries that are arranged in parallel. The parallel-arranged twin boundaries include 90% or more [111] crystal orientation.

A bonding structure is provided, wherein the bonding structure includes a first substrate, a second substrate, a first adhesive layer, a second adhesive layer, and a silver feature. The second substrate is disposed opposite to the first substrate. The first adhesive layer is disposed on the first substrate. The second adhesive layer is disposed on the second substrate and opposite the first adhesive layer. The silver feature is disposed between the first adhesive layer and the second adhesive layer. The silver feature includes a silver nano-twinned structure that includes twin boundaries that are arranged in parallel. The parallel-arranged twin boundaries include 90% or more [111] crystal orientation.

Embodiments of the present disclosure include method for sequentially mounting multiple semiconductor devices onto a substrate having a composite metal structure on both the semiconductor devices and the substrate for improved process tolerance and reduced device distances without thermal interference. The mounting process causes “selective” intermixing between the metal layers on the devices and the substrate and increases the melting point of the resulting alloy materials.

Embodiments of the present disclosure include method for sequentially mounting multiple semiconductor devices onto a substrate having a composite metal structure on both the semiconductor devices and the substrate for improved process tolerance and reduced device distances without thermal interference. The mounting process causes “selective” intermixing between the metal layers on the devices and the substrate and increases the melting point of the resulting alloy materials.

A die bonding structure is provided. The die bonding structure includes a chip, an adhesive layer under the chip, a bonding layer under the adhesive layer, and a heat dissipation substrate under the bonding layer. The bonding layer includes a silver nano-twinned thin film, which has parallel-arranged twin boundaries. The parallel-arranged twin boundaries include at least 90% of [111] crystal orientation.

A die bonding structure is provided. The die bonding structure includes a chip, an adhesive layer under the chip, a bonding layer under the adhesive layer, and a heat dissipation substrate under the bonding layer. The bonding layer includes a silver nano-twinned thin film, which has parallel-arranged twin boundaries. The parallel-arranged twin boundaries include at least 90% of [111] crystal orientation.