Encapsulated stress mitigation layers and assemblies having the same are disclosed. An assembly that includes a first substrate, a second substrate, an encapsulating layer disposed between the first and second substrates, and a stress mitigation layer disposed in the encapsulating layer such that the stress mitigation layer is encapsulated within the encapsulating layer. The stress mitigation layer has a lower melting temperature relative to a higher melting temperature of the encapsulating layer. The assembly includes an intermetallic compound layer disposed between the first substrate and the encapsulating layer such that the encapsulating layer is separated from the first substrate by the intermetallic compound layer. The stress mitigation layer melts into a liquid when the assembly operates at a temperature above the low melting temperature of the stress mitigation layer and the encapsulating layer maintains the liquid of the stress mitigation layer within the assembly.

Encapsulated stress mitigation layers and assemblies having the same are disclosed. An assembly that includes a first substrate, a second substrate, an encapsulating layer disposed between the first and second substrates, and a stress mitigation layer disposed in the encapsulating layer such that the stress mitigation layer is encapsulated within the encapsulating layer. The stress mitigation layer has a lower melting temperature relative to a higher melting temperature of the encapsulating layer. The assembly includes an intermetallic compound layer disposed between the first substrate and the encapsulating layer such that the encapsulating layer is separated from the first substrate by the intermetallic compound layer. The stress mitigation layer melts into a liquid when the assembly operates at a temperature above the low melting temperature of the stress mitigation layer and the encapsulating layer maintains the liquid of the stress mitigation layer within the assembly.

A semiconductor element bonding body including: a substrate, in which a concave portion is formed; and a semiconductor element placed in the concave portion to be mounted to the substrate. A portion of the substrate in which the concave portion is formed is made of Cu. The concave portion has a perimeter portion in which a level difference is formed, and the level difference has a height d of 20 m or more and less than 50 m. The concave portion has a bottom surface having a flatness degree of /8.7 m or more and /1.2 m or less when a wavelength of a laser is 632.8 nm. A metal film is formed on the semiconductor element, and the bottom surface of the concave portion and the metal film are bonded directly to each other.

Provided is a copper paste for joining including copper particles, second particles including a metal element other than copper, and a dispersion medium, in which the copper particles include submicro copper particles having a volume-average particle diameter of 0.12 m or more and 0.8 m or less and micro copper particles having a volume-average particle diameter of 2 m or more and 50 m or less, a sum of a content of the submicro copper particles and a content of the micro copper particles is 80% by mass or more of a sum of masses of the copper particles and the second particles, the content of the submicro copper particles is 30% by mass or more and 90% by mass or less of a sum of a mass of the submicro copper particles and a mass of the micro copper particles, and a content of the second particles is 0.01% by mass or more and 10% by mass or less of the sum of the masses of the copper particles and the second particles.

A package structure includes a substrate, a first capacitor, a System on Chip unit and a wiring layer. The first capacitor is provided on the substrate. The System on Chip unit is bonded with the first capacitor in a first dielectric layer. The wiring layer is configured to electrically couple the first capacitor and the System on Chip unit. The wiring layer is provided on the first dielectric layer through a second dielectric layer.

A package structure includes a substrate, a first capacitor, a System on Chip unit and a wiring layer. The first capacitor is provided on the substrate. The System on Chip unit is bonded with the first capacitor in a first dielectric layer. The wiring layer is configured to electrically couple the first capacitor and the System on Chip unit. The wiring layer is provided on the first dielectric layer through a second dielectric layer.

In an embodiment, a quantum device includes an interposer layer comprising a set of vias. In an embodiment, the quantum device includes a dielectric layer formed on a first side of the interposer, the dielectric layer including a set of transmission lines communicatively coupled to the set of vias. In an embodiment, the quantum device includes a plurality of qubit chips coupled to an opposite side of the interposer layer, each qubit chip of the plurality of qubit chips including: a plurality of qubits on a first side of the qubit chip and a plurality of protrusions on a second side of the qubit chip. In an embodiment, the quantum device includes a heat sink thermally coupled with the plurality of qubit chips, the heat sink comprising a plurality of recesses aligned with the plurality of protrusions of the plurality of qubit chips.

In an embodiment, a quantum device includes an interposer layer comprising a set of vias. In an embodiment, the quantum device includes a dielectric layer formed on a first side of the interposer, the dielectric layer including a set of transmission lines communicatively coupled to the set of vias. In an embodiment, the quantum device includes a plurality of qubit chips coupled to an opposite side of the interposer layer, each qubit chip of the plurality of qubit chips including: a plurality of qubits on a first side of the qubit chip and a plurality of protrusions on a second side of the qubit chip. In an embodiment, the quantum device includes a heat sink thermally coupled with the plurality of qubit chips, the heat sink comprising a plurality of recesses aligned with the plurality of protrusions of the plurality of qubit chips.

A method of attaching a semiconductor chip to a lead frame, including A) providing a semiconductor chip, B) applying a solder metal layer sequence on the semiconductor chip, C) providing a lead frame, D) applying a metallization layer sequence on the lead frame, E) applying the semiconductor chip on the lead frame via the solder metal layer sequence and the metallization layer sequence, and F) heating the arrangement produced under E) to attach the semiconductor chip to the lead frame, wherein the solder metal layer sequence includes a first metallic layer including an indium-tin alloy, a barrier layer arranged above the first metallic layer, and a second metallic layer including gold arranged between the barrier layer and the semiconductor chip.

A method of attaching a semiconductor chip to a lead frame, including A) providing a semiconductor chip, B) applying a solder metal layer sequence on the semiconductor chip, C) providing a lead frame, D) applying a metallization layer sequence on the lead frame, E) applying the semiconductor chip on the lead frame via the solder metal layer sequence and the metallization layer sequence, and F) heating the arrangement produced under E) to attach the semiconductor chip to the lead frame, wherein the solder metal layer sequence includes a first metallic layer including an indium-tin alloy, a barrier layer arranged above the first metallic layer, and a second metallic layer including gold arranged between the barrier layer and the semiconductor chip.