A semiconductor device includes: a semiconductor die having a metal region; a substrate having a metal region; and a soldered joint between the metal region of the semiconductor die and the metal region of the substrate. One or more intermetallic phases are present throughout the entire soldered joint, each of the one or more intermetallic phases formed from a solder preform diffused into the metal region of the semiconductor die and the metal region of the substrate. The soldered joint has the same length-to-width aspect ratio as the semiconductor die.

A semiconductor device includes: a semiconductor die having a metal region; a substrate having a metal region; and a soldered joint between the metal region of the semiconductor die and the metal region of the substrate. One or more intermetallic phases are present throughout the entire soldered joint, each of the one or more intermetallic phases formed from a solder preform diffused into the metal region of the semiconductor die and the metal region of the substrate. The soldered joint has the same length-to-width aspect ratio as the semiconductor die.

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 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.

Provided is a method for manufacturing a semiconductor device that improves the reliability of the semiconductor device under thermal stress and the assembly performance of the semiconductor device in manufacturing steps. The method includes the following: forming a first electrode by depositing a first conductive film onto one main surface of a semiconductor substrate and patterning the first conductive film; forming a first metal film corresponding to a pattern of the first electrode onto the first electrode; forming a second electrode by depositing a second conductive film onto the other main surface of the semiconductor substrate; forming a second metal film thinner than the first metal film onto the second electrode; and collectively forming a third metal film onto each of the first metal film and the second metal film by electroless plating.

Provided is a method for manufacturing a semiconductor device that improves the reliability of the semiconductor device under thermal stress and the assembly performance of the semiconductor device in manufacturing steps. The method includes the following: forming a first electrode by depositing a first conductive film onto one main surface of a semiconductor substrate and patterning the first conductive film; forming a first metal film corresponding to a pattern of the first electrode onto the first electrode; forming a second electrode by depositing a second conductive film onto the other main surface of the semiconductor substrate; forming a second metal film thinner than the first metal film onto the second electrode; and collectively forming a third metal film onto each of the first metal film and the second metal film by electroless plating.

A package comprising an electronic chip, a laminate type encapsulant in and/or on which the electronic chip is mounted, a solderable electric contact on a solder surface of the package, and a solder flow path on and/or in the package which is configured so that, upon soldering the electric contact with a mounting base, part of solder material flows along the solder flow path towards a surface of the package at which the solder material is optically inspectable after completion of the solder connection between the mounting base and the electric contact.

A method for producing a semiconductor package in which a plurality of semiconductor chips, each of which includes a substrate, conductive portions formed on the substrate, and microbumps formed on the conductive portions, are laminated, which includes a smooth surface formation process of forming a smooth surface on the microbump, a lamination process of laminating three or more of the semiconductor chips by overlaying the microbump of one of the semiconductor chips on the microbump of another one of the semiconductor chips, and a bonding process of bonding the semiconductor chips to each other via the microbumps by heating to melt the microbumps, in which in the lamination process, of one of the semiconductor chips and another one of the semiconductor chips, the smooth surface is formed on at least one of the microbump, and one of the microbump contacts another one of the microbump on the smooth surface.

A method for producing a semiconductor package in which a plurality of semiconductor chips, each of which includes a substrate, conductive portions formed on the substrate, and microbumps formed on the conductive portions, are laminated, which includes a smooth surface formation process of forming a smooth surface on the microbump, a lamination process of laminating three or more of the semiconductor chips by overlaying the microbump of one of the semiconductor chips on the microbump of another one of the semiconductor chips, and a bonding process of bonding the semiconductor chips to each other via the microbumps by heating to melt the microbumps, in which in the lamination process, of one of the semiconductor chips and another one of the semiconductor chips, the smooth surface is formed on at least one of the microbump, and one of the microbump contacts another one of the microbump on the smooth surface.

Techniques are employed to mitigate the anchoring effects of cavity sidewall adhesion on an embedded conductive interconnect structure, and to allow a lower annealing temperature to be used to join opposing conductive interconnect structures. A vertical gap may be disposed between the conductive material of an embedded interconnect structure and the sidewall of the cavity to laterally unpin the conductive structure and allow uniaxial expansion of the conductive material. Additionally or alternatively, one or more vertical gaps may be disposed within the bonding layer, near the embedded interconnect structure to laterally unpin the conductive structure and allow uniaxial expansion of the conductive material.