A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.

A semiconductor package includes an interposer chip having a frontside, a backside, and a corner area on the backside defined by a first corner edge and a second corner edge of the interposer chip. A die is bonded to the frontside of the interposer chip. At least one dam structure is formed on the corner area of the backside of the interposer chip. The dam structure includes an edge aligned to at least one the first corner edge and the second corner edge of the interposer chip.

A microelectronic device has a pillar connected to an external terminal by an intermetallic joint. Either the pillar or the external terminal, or both, include copper in direct contact with the intermetallic joint. The intermetallic joint includes at least 90 weight percent of at least one copper-tin intermetallic compound. The intermetallic joint is free of voids having a combined volume greater than 10 percent of a volume of the intermetallic joint; and free of a void having a volume greater than 5 percent of the volume of the intermetallic joint. The microelectronic device may be formed using solder which includes at least 93 weight percent tin, 0.5 weight percent to 5.0 weight percent silver, and 0.4 weight percent to 1.0 weight percent copper, to form a solder joint between the pillar and the external terminal, followed by thermal aging to convert the solder joint to the intermetallic joint.

A package structure and a method for fabricating the same are provided. The package structure includes a substrate, a semiconductor package and an adhesive body. The substrate has a first board surface and a second board surface. The semiconductor package has an upper surface and a lower surface, is disposed on the first board surface and electrically connected to the substrate through pins, and has a first vertical projection on the first board surface. An adhesive groove is disposed on the first board surface and is located in at least one portion of the first vertical projection and a periphery of the first vertical projection. The adhesive body is disposed in the adhesive groove, and protrudes to contact the lower surface, so as to fix the semiconductor package. The adhesive groove does not overlap with the pins, and the adhesive body does not contact the pins.

In an embodiment, a method comprises: configuring a direct conversion compound semiconductor sensor over a first surface of a readout integrated circuit, IC, comprising two surfaces, each surface comprising solder material on the surface; illuminating the solder material with an infra-red laser such that the solder material on the readout IC melts and forms solder joints between the readout IC and the direct conversion compound semiconductor sensor; configuring a substrate over a second surface of the readout IC comprising solder material; and illuminating the solder material of the second surface with the infra-red laser such that the solder material on the readout IC melts and electrically connects the readout IC with the substrate. In other embodiments, a high frequency radiation detector and an imaging apparatus are discussed.

A semiconductor package includes an interposer chip having a frontside, a backside, and a corner area on the backside defined by a first corner edge and a second corner edge of the interposer chip. A die is bonded to the frontside of the interposer chip. At least one dam structure is formed on the corner area of the backside of the interposer chip. The dam structure includes an edge aligned to at least one the first corner edge and the second corner edge of the interposer chip.

A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.

A die bonding process for assembling a semiconductor device includes the steps of applying a sintered-silver-use paste to each of a plurality of first regions on an upper surface of a chip mounting part, drying the sintered-silver-use paste and applying a silver paste to a second region located between/among the respective first regions. Further, the process includes the step of mounting a semiconductor chip onto the chip mounting part in such a manner that a rear surface of the semiconductor chip faces an upper surface of the chip mounting part with the sintered-silver-use paste and the silver paste being interposed. After mounting the chip, part of each of first, second, third and fourth corners of a principal surface of the semiconductor chip is located in each of the first regions.

A die bonding process for assembling a semiconductor device includes the steps of applying a sintered-silver-use paste to each of a plurality of first regions on an upper surface of a chip mounting part, drying the sintered-silver-use paste and applying a silver paste to a second region located between/among the respective first regions. Further, the process includes the step of mounting a semiconductor chip onto the chip mounting part in such a manner that a rear surface of the semiconductor chip faces an upper surface of the chip mounting part with the sintered-silver-use paste and the silver paste being interposed. After mounting the chip, part of each of first, second, third and fourth corners of a principal surface of the semiconductor chip is located in each of the first regions.

A method for manufacturing a metal bump device includes providing a substrate structure including a substrate and a metal layer having a recess on the substrate, forming a metal bump on the recess of the metal layer using a ball placement process, and forming a solder paste on the metal bump using a printing process. The manufacturing time is shorter, the manufacturing efficiency is higher, and the manufacturing cost is lower than conventional manufacturing methods.