An electronic component-mounted body (1) in accordance with an embodiment of the present invention is configured such that an IC chip (20) is fixed, with use of a post (30) having a thermosetting property, to a wiring substrate (10) having an anisotropic linear expansion coefficient.

A quad flat no lead package is provided comprising at least one first integrated circuit die embedded in a recess in a die paddle of a metal leadframe and a second integrated circuit chip die attached to the at least one first integrated circuit die wherein the first and second integrated circuit dies are electrically connected to each other and wherein the second integrated circuit die is connected to leads of the leadframe through copper pillars.

A solder connection may be surrounded by a solder locking layer (1210, 2210) and may be recessed in a hole (1230) in that layer. The recess may be obtained by evaporating a vaporizable portion (1250) of the solder connection. Other features are also provided.

Systems and techniques that facilitate uniform qubit chip gaps via injection-molded solder pillars are provided. In various embodiments, a device can comprise one or more injection-molded solder interconnects. In various aspects, the one or more injection-molded solder interconnects can couple at least one qubit chip to an interposer chip. In various embodiments, the device can further comprise one or more injection-molded solder pillars. In various instances, the one or more injection-molded solder pillars can be between the at least one quit chip and the interposer chip. In various cases, the one or more injection-molded solder pillars can be in parallel with the one or more injection-molded solder interconnects. In various embodiments, the one or more injection-molded solder pillars can facilitate and/or maintain a uniform gap between the at least one qubit chip and the interposer chip. In various embodiments, a melting point of the one or more injection-molded solder pillars can be higher than a melting point of the one or more injection-molded solder interconnects. In various embodiments, the one or more injection-molded solder pillars can be superconductors. In various embodiments, a yield strength of the one or more injection-molded solder pillars can be between 3,000 pounds per square inch and 15,000 pounds per square inch, which can be higher than a yield strength of the one or more injection-molded solder interconnects. In various embodiments, the one or more injection-molded solder pillars can be binary tin alloys, tertiary tin alloys, and/or quaternary tin alloys.

Microelectronic assemblies, and related devices and methods, are disclosed herein. For example, in some embodiments, a microelectronic assembly may include a package substrate having a first surface and an opposing second surface, and a die secured to the package substrate, wherein the die has a first surface and an opposing second surface, the die has first conductive contacts at the first surface and second conductive contacts at the second surface, and the first conductive contacts are coupled to conductive pathways in the package substrate by first non-solder interconnects.

A method forming an interconnect structure includes depositing a first solder bump on a chip; depositing a second solder bump on a laminate, the second solder bump including a nickel copper colloid surrounded by a nickel or copper shell and suspended in a tin-based solder; aligning the chip with the laminate; performing a first reflow process to join the chip to the laminate; depositing an underfill material around the first solder bump and the second solder bump; and performing a second reflow process at a temperature that is lower than the first reflow process to convert the first solder bump and the second solder bump to an all intermetallic interconnect; wherein depositing the underfill material is performed before or after performing the second reflow process.

A method forming an interconnect structure includes depositing a first solder bump on a chip; depositing a second solder bump on a laminate, the second solder bump including a nickel copper colloid surrounded by a nickel or copper shell and suspended in a tin-based solder; aligning the chip with the laminate; performing a first reflow process to join the chip to the laminate; depositing an underfill material around the first solder bump and the second solder bump; and performing a second reflow process at a temperature that is lower than the first reflow process to convert the first solder bump and the second solder bump to an all intermetallic interconnect; wherein depositing the underfill material is performed before or after performing the second reflow process.

A method forming an interconnect structure includes depositing a first solder bump on a chip; depositing a second solder bump on a laminate, the second solder bump including a nickel copper colloid surrounded by a nickel or copper shell and suspended in a tin-based solder; aligning the chip with the laminate; performing a first reflow process to join the chip to the laminate; depositing an underfill material around the first solder bump and the second solder bump; and performing a second reflow process at a temperature that is lower than the first reflow process to convert the first solder bump and the second solder bump to an all intermetallic interconnect; wherein depositing the underfill material is performed before or after performing the second reflow process.

Semiconductor devices and methods of manufacture thereof are disclosed. In some embodiments, a semiconductor device includes a substrate, and a plurality of contact pads disposed over the substrate. The contact pads may be arranged in a ball grid array (BGA), and the may include a plurality of corners. A metal dam is disposed around each of the plurality of corners, such as corners of the BGA.

Proximity coupling interconnect packaging systems and methods. A semiconductor package assembly comprises a substrate, a first semiconductor die disposed adjacent the substrate, and a second semiconductor die stacked over the first semiconductor die. There is at least one proximity coupling interconnect between the first semiconductor die and the second semiconductor die, the proximity coupling interconnect comprising a first conductive pad on the first coupling face on the first semiconductor die and a second conductive pad on a second coupling face of the second semiconductor die, the second conductive pad spaced apart from the first conductive pad by a gap distance and aligned with the first conductive pad. An electrical connector is positioned laterally apart from the proximity coupling interconnect and extends between the second semiconductor die and the substrate, the position of the electrical connector defining the alignment of the first conductive pad and the second conductive pad.