A method of forming a microelectronic device structure comprises coiling a portion of a wire up and around at least one sidewall of a structure protruding from a substrate. At least one interface between an upper region of the structure and an upper region of the coiled portion of the wire is welded to form a fused region between the structure and the wire.

A method of ultrasonically bonding semiconductor elements includes the steps of: (a) aligning surfaces of a plurality of first conductive structures of a first semiconductor element to respective surfaces of a plurality of second conductive structures of a second semiconductor element; and (b) ultrasonically bonding ones of the first conductive structures to respective ones of the second conductive structures. A bonding surface of at least one of the first conductive structures and the second conductive structures includes a frangible coating.

A method of ultrasonically bonding semiconductor elements includes the steps of: (a) aligning surfaces of a plurality of first conductive structures of a first semiconductor element to respective surfaces of a plurality of second conductive structures of a second semiconductor element; and (b) ultrasonically bonding ones of the first conductive structures to respective ones of the second conductive structures. A bonding surface of at least one of the first conductive structures and the second conductive structures includes a frangible coating.

A method of forming a microelectronic device structure comprises coiling a portion of a wire up and around at least one sidewall of a structure protruding from a substrate. At least one interface between an upper region of the structure and an upper region of the coiled portion of the wire is welded to form a fused region between the structure and the wire.

A method of forming a microelectronic device structure comprises coiling a portion of a wire up and around at least one sidewall of a structure protruding from a substrate. At least one interface between an upper region of the structure and an upper region of the coiled portion of the wire is welded to form a fused region between the structure and the wire.

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.

Technologies for radiofrequency optimized interconnects for a quantum processor are disclosed. In the illustrative embodiment, signals are carried in coplanar waveguides on a surface of a quantum processor die. A ground ring surrounds the signals and is connected to the ground conductors of each coplanar waveguide. Wire bonds connect the ground ring to a ground of a circuit board. The wire bonds provide both an electrical connection from the quantum processor die to the circuit board as well as increased thermal coupling between the quantum processor die and the circuit board, increasing cooling of the quantum processor die.