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.

An IC chip package includes a substrate having a plurality of interconnect metal pads, and a chip having a plurality of interconnect metal pads arranged thereon. An interconnect solder structure electrically connects each of the plurality of interconnect metal pads. The chip is devoid of the interconnect solder structures and interconnect metal pads at one or more corners of the chip. Rather, a dummy solder structure connects the IC chip to the substrate at each of the one or more corners of the IC chip, and the dummy solder structure is directly under at least one side of the IC chip at the one or more corners of the IC chip. The dummy solder structure has a larger volume than a volume of each of the plurality of interconnect solder structures. The dummy solder structure eliminates a chip-underfill interface at corner(s) of the chip where delamination would occur.

Provided is a semiconductor element mounting structure, including: a semiconductor element including an element electrode, and a substrate including a substrate electrode that is provided on a surface facing the semiconductor element at a position facing the element electrode, the semiconductor element and the substrate being connected via the element electrode and the substrate electrode, in which: one of the element electrode or the substrate electrode is a first protruding electrode including a solder layer at a tip portion thereof, the other of the element electrode or the substrate electrode is a first electrode pad including one or more metal protrusions on a surface thereof, the one or more metal protrusions of the first electrode pad extend into the solder layer of the first protruding electrode, and a bottom area of each of the one or more metal protrusions of the first electrode pad is 70% or less with respect to an area of the first electrode pad, or 75% or less with respect to a maximum cross-sectional area of the solder layer of the first protruding electrode.

Improved electrical and thermal properties of solder alloys are achieved by the use of micro-additives in solder alloys to engineer the electrical and thermal properties of the solder alloys and the properties of the reaction layers between the solder and the metal surfaces. The electrical and thermal conductivity of alloys and that of the reaction layers between the solder and the -metal surfaces can be controlled over a wide range of temperatures. The solder alloys produce stable microstructures wherein such stable microstructures of these alloys do not exhibit significant changes when exposed to changes in temperature, compared to traditional interconnect materials.

Provided are a hybrid bonding structure, a solder paste composition, a semiconductor device, and a method of manufacturing the semiconductor device. The hybrid bonding structure includes a solder ball and a solder paste bonded to the solder ball. The solder paste includes a transient liquid phase. The transient liquid phase includes a core and a shell on a surface of the core. A melting point of the shell may be lower than a melting point of the core. The core and the shell are configured to form an intermetallic compound in response to the transient liquid phase at least partially being at a temperature that is within a temperature range of about 20° C. to about 190° C.

Provided is a method of fabricating a semiconductor package. The method of fabricating the semiconductor package include preparing a lower element including a lower substrate, a lower electrode, an UBM layer, and a reducing agent layer, providing an upper element including an upper substrate, an upper electrode, and a solder bump layer, providing a pressing member on the upper substrate to press the upper substrate to the lower substrate, and providing a laser beam passing through the pressing member to bond the upper element to the lower element.

A method for producing an optoelectronic component and an optoelectronic component are disclosed. In an embodiment a method includes providing a semiconductor chip having an active region for radiation emission, applying a seed layer on the semiconductor chip, wherein the seed layer includes a first metal and a second metal being different from the first metal, and wherein the second metal is less noble than the first metal, applying a structured photoresist layer directly to the seed layer, applying a solder layer at least to regions of the seed layer which are not covered by the photoresist layer and wherein a proportion of the second metal in the seed layer is between 0.5 wt % and 10 wt %.

A method for producing an optoelectronic component and an optoelectronic component are disclosed. In an embodiment a method includes providing a semiconductor chip having an active region for radiation emission, applying a seed layer on the semiconductor chip, wherein the seed layer includes a first metal and a second metal being different from the first metal, and wherein the second metal is less noble than the first metal, applying a structured photoresist layer directly to the seed layer and applying a solder layer at least to regions of the seed layer which are not covered by the photoresist layer, wherein a ratio of the first metal to the second metal in the seed layer is between 95:5 to 99:1.

An IC chip package includes a substrate having a plurality of interconnect metal pads, and a chip having a plurality of interconnect metal pads arranged thereon. An interconnect solder structure electrically connects each of the plurality of interconnect metal pads. The chip is devoid of the interconnect solder structures and interconnect metal pads at one or more corners of the chip. Rather, a dummy solder structure connects the IC chip to the substrate at each of the one or more corners of the IC chip, and the dummy solder structure is directly under at least one side of the IC chip at the one or more corners of the IC chip. The dummy solder structure has a larger volume than a volume of each of the plurality of interconnect solder structures. The dummy solder structure eliminates a chip-underfill interface at corner(s) of the chip where delamination would occur.

Photonic devices include a photonic assembly and a substrate coupled to the photonic assembly. The photonic assembly includes a photonic die and an optical device coupled to the photonic die with an adhesive to form an optical connection between the optical device and the photonic die. The photonic assembly is coupled to the photonic assembly by reflowing a plurality of solder connections at temperature that is less than a cure temperature of the adhesive.