The present disclosure is directed to a wafer level chip scale package (WLCSP) with various combinations of contacts and Under Bump Metallizations (UBMs) having different structures and different amounts solder coupled to the contacts and UBMs. Although the contacts have different structures and the volume of solder differs, the total standoff height along the WLCSP remains substantially the same. Each portion of solder coupled to each respective contact and UBM includes a point furthest away from an active surface of a die of the WLCSP. Each point of each respective portion of solder is co-planar with each other respective point of the other respective portions of solder. Additionally, the contacts with various and different structures are positioned accordingly on the active surface of the die of the WLCSP.

The present disclosure is directed to a wafer level chip scale package (WLCSP) with various combinations of contacts and Under Bump Metallizations (UBMs) having different structures and different amounts solder coupled to the contacts and UBMs. Although the contacts have different structures and the volume of solder differs, the total standoff height along the WLCSP remains substantially the same. Each portion of solder coupled to each respective contact and UBM includes a point furthest away from an active surface of a die of the WLCSP. Each point of each respective portion of solder is co-planar with each other respective point of the other respective portions of solder. Additionally, the contacts with various and different structures are positioned accordingly on the active surface of the die of the WLCSP.

Methods of coupling inductors in an IC device using interconnecting elements with solder caps and the resulting device are disclosed. Embodiments include forming a top inductor structure, in a top inductor area on a lower surface of a top substrate, the top inductor structure having first and second top terminals at its opposite ends; forming a bottom inductor structure, in a bottom inductor area on an upper surface of a bottom substrate, the bottom inductor structure having first and second bottom terminals at its opposite ends; forming top interconnecting elements on the lower surface of the top substrate around the top inductor area; forming bottom interconnecting elements on the upper surface of the bottom substrate around the bottom inductor area; forming solder bumps on lower and upper surfaces, respectively, of the top and bottom interconnecting elements; and connecting the top and bottom interconnecting elements to each other.

Methods of coupling inductors in an IC device using interconnecting elements with solder caps and the resulting device are disclosed. Embodiments include forming a top inductor structure, in a top inductor area on a lower surface of a top substrate, the top inductor structure having first and second top terminals at its opposite ends; forming a bottom inductor structure, in a bottom inductor area on an upper surface of a bottom substrate, the bottom inductor structure having first and second bottom terminals at its opposite ends; forming top interconnecting elements on the lower surface of the top substrate around the top inductor area; forming bottom interconnecting elements on the upper surface of the bottom substrate around the bottom inductor area; forming solder bumps on lower and upper surfaces, respectively, of the top and bottom interconnecting elements; and connecting the top and bottom interconnecting elements to each other.

A method for bonding two superconducting integrated circuits (“chips”), such that the bonds electrically interconnect the chips. A plurality of indium-coated metallic posts may be deposited on each chip. The indium bumps are aligned and compressed with moderate pressure at a temperature at which the indium is deformable but not molten, forming fully superconducting connections between the two chips when the indium is cooled down to the superconducting state. An anti-diffusion layer may be applied below the indium bumps to block reaction with underlying layers. The method is scalable to a large number of small contacts on the wafer scale, and may be used to manufacture a multi-chip module comprising a plurality of chips on a common carrier. Superconducting classical and quantum computers and superconducting sensor arrays may be packaged.

A method for bonding two superconducting integrated circuits (“chips”), such that the bonds electrically interconnect the chips. A plurality of indium-coated metallic posts may be deposited on each chip. The indium bumps are aligned and compressed with moderate pressure at a temperature at which the indium is deformable but not molten, forming fully superconducting connections between the two chips when the indium is cooled down to the superconducting state. An anti-diffusion layer may be applied below the indium bumps to block reaction with underlying layers. The method is scalable to a large number of small contacts on the wafer scale, and may be used to manufacture a multi-chip module comprising a plurality of chips on a common carrier. Superconducting classical and quantum computers and superconducting sensor arrays may be packaged.

A package that includes a first integrated device comprising a first plurality of interconnects; a plurality of solder interconnects coupled to the first plurality of interconnects; a second integrated device comprising a second plurality of interconnects, wherein the second integrated device is coupled to the first integrated device through the second plurality of interconnects, the plurality of solder interconnects and the first plurality of interconnects; a polymer layer located between the first integrated device and the second integrated device; and a plurality of spacer balls located between the first integrated device and the second integrated device.

A package that includes a first integrated device comprising a first plurality of interconnects; a plurality of solder interconnects coupled to the first plurality of interconnects; a second integrated device comprising a second plurality of interconnects, wherein the second integrated device is coupled to the first integrated device through the second plurality of interconnects, the plurality of solder interconnects and the first plurality of interconnects; a polymer layer located between the first integrated device and the second integrated device; and a plurality of spacer balls located between the first integrated device and the second integrated device.

Disclosed are examples of integrated circuit (IC) structures and techniques to fabricate IC structures. Each IC package may include a die (e.g., a flip-chip (FC) die) and one or more die interconnects to electrically couple the die to a substrate. The die interconnect may include a pillar, a wetting barrier on the pillar, and a solder cap on the wetting barrier. The wetting barrier may be wider than the pillar. The die interconnect may also include a low wetting layer formed on the wetting barrier.

Disclosed are examples of integrated circuit (IC) structures and techniques to fabricate IC structures. Each IC package may include a die (e.g., a flip-chip (FC) die) and one or more die interconnects to electrically couple the die to a substrate. The die interconnect may include a pillar, a wetting barrier on the pillar, and a solder cap on the wetting barrier. The wetting barrier may be wider than the pillar. The die interconnect may also include a low wetting layer formed on the wetting barrier.