A semiconductor device includes a semiconductor die including a first side and an opposing second side, a first metallization layer arranged on the first side, a Ni including layer arranged on the second side, wherein the Ni including layer further includes one or more of Si, Cr and Ti, and a SnSb layer arranged on the Ni comprising layer, wherein an amount of Sb in the SnSb layer is in the range of 2 wt % to 30 wt %.

A method of soldering includes providing a substrate having a first metal joining surface, providing a semiconductor die having a second metal joining surface, providing a solder preform having a first interface surface and a second interface surface, arranging the solder preform between the substrate and the semiconductor die such that the first interface surface faces the first metal joining surface and such that the second interface surface faces the second metal joining surface, and performing a mechanical pressure-free diffusion soldering process that forms a soldered joint between the substrate and the semiconductor die by melting the solder preform and forming intermetallic phases in the solder. One or both of the first interface surface and the second interface surface has a varying surface profile that creates voids between the solder preform and one or both of the substrate and the semiconductor die before the melting of the solder preform.

A method of joining a semiconductor die to a substrate includes: applying a solder preform to a metal region of the semiconductor die or to a metal region of the substrate, the solder preform having a maximum thickness of 30 μm and a lower melting point than both metal regions; forming a soldered joint between the metal region of the semiconductor die and the metal region of the substrate via a diffusion soldering process and without applying pressure directly to the die; and setting a soldering temperature of the diffusion soldering process so that the solder preform melts and fully reacts with the metal region of the semiconductor die and the metal region of the substrate to form one or more intermetallic phases throughout the entire soldered joint, each intermetallic phase having a melting point above the melting point of the preform and the soldering temperature.

A semiconductor package includes a power semiconductor chip comprising SiC, a leadframe part comprising Cu, wherein the power semiconductor chip is arranged on the leadframe part, and a solder joint electrically and mechanically coupling the power semiconductor chip to the leadframe part, wherein the solder joint comprises at least one intermetallic phase.

A semiconductor device includes first and second semiconductor elements and first and second conductive members. A first electrode on the first semiconductor element is bonded to a first stack part of the first conductive member by a first bonding layer. A second electrode on the second semiconductor element is bonded to a second stack part of the second conductive member by a second bonding layer. A first joint part of the first conductive member is bonded to a second joint part of the second conductive member by an intermediate bonding layer. A first surface of the first joint part facing the second joint part, a side surface of the first joint part continuous from the first surface, a second surface of the second joint part facing the first joint part, and a side surface of the second joint part continuous from the second surface are covered by nickel layers.

A semiconductor assembly includes a substrate including a metal die attach surface, a semiconductor die that is arranged on the substrate, the semiconductor die being configured as a power semiconductor device and comprising a semiconductor body, a rear side metallization, and a front side layer stack, the front side layer stack comprising a front side metallization and a contaminant protection layer that is between the front side metallization and the semiconductor body, and a diffusion soldered joint between the metal die attach surface and the rear side metallization, the diffusion soldered joint comprising one or more intermetallic phases throughout the diffusion soldered joint, wherein the contaminant protection layer is configured to prevent transmission of contaminants into the semiconductor body.

A method of forming a chip assembly may include forming a plurality of cavities in a carrier; The method may further include arranging a die attach liquid in each of the cavities; arranging a plurality of chips on the die attach liquid, each chip comprising a rear side metallization and a rear side interconnect material disposed over the rear side metallization, wherein the rear side interconnect material faces the carrier; evaporating the die attach liquid; and after the evaporating the die attach liquid, fixing the plurality of chips to the carrier.

A method of forming a chip assembly may include forming a plurality of cavities in a carrier; The method may further include arranging a die attach liquid in each of the cavities; arranging a plurality of chips on the die attach liquid, each chip comprising a rear side metallization and a rear side interconnect material disposed over the rear side metallization, wherein the rear side interconnect material faces the carrier; evaporating the die attach liquid; and after the evaporating the die attach liquid, fixing the plurality of chips to the carrier.

A semiconductor device includes: a semiconductor element; a joined member that is joined to the semiconductor element and includes a nickel film; and a joining layer that is joined to the joined member and contains 2.0 wt % or higher of copper, in which the joining layer includes a solder portion and a Cu.sub.6Sn.sub.5 portion, base metal of the solder portion contains at least tin as a constituent element and contains elemental copper, and the Cu.sub.6Sn.sub.5 portion is in contact with the nickel film.

The present invention relates to a method of forming a joint bonding together two solid objects and joints made by the method, where the joint is formed by a layer of a binary system which upon heat treatment forms a porous, coherent and continuous single solid-solution phase extending across a bonding layer of the joint.