A method for producing a joined structure according to the present invention includes: a reflow step of heating a first member and a solder material while keeping them in contact with each other in a reflow chamber to melt a solder alloy constituting the solder material, the reflow step including: a first reflow step of melting the solder alloy with an atmosphere in the reflow chamber reduced to a first pressure P.sub.1 lower than the atmospheric pressure; and a second reflow step of, after the first reflow step, melting the solder alloy with the atmosphere in the reflow chamber reduced to a second pressure P.sub.2 lower than the first pressure P.sub.1.

The present disclosure is directed to a compact vertical oven for reflow of solder bumps for backend processes in semiconductor wafer assembly and packaging. This disclosure describes a vertical oven which uses a plurality of wafers (e.g., an example value is 50-100 wafers) in a batch with controlled injection of the reducing agent (e.g. formic acid), resulting in a process largely free of contamination. This disclosure describes controlled formic acid flow through a vertical system using laminar flow technology in a sub-atmospheric pressure environment, which is not currently available in the industry. The efficacy of the process depends on effective formic acid vapor delivery, integrated temperature control during heating and cooling, and careful design of the vapor flow path with exhaust. Zone-dependent reaction dynamics managed by vapor delivery process, two-steps temperature ramp control, and controlled cooling process and formic acid content ensures the effective reaction without any flux.

A semiconductor device includes a substrate; a die attached over the substrate; and a metal enclosure continuously encircling a space and extending vertically between the substrate and the die.

A method for producing a joined structure according to the present invention includes: a reflow step of heating a first member and a solder material while keeping them in contact with each other in a reflow chamber to melt a solder alloy constituting the solder material, the reflow step including: a first reflow step of melting the solder alloy with an atmosphere in the reflow chamber reduced to a first pressure P.sub.1 lower than the atmospheric pressure; and a second reflow step of, after the first reflow step, melting the solder alloy with the atmosphere in the reflow chamber reduced to a second pressure P.sub.2 lower than the first pressure P.sub.1.

A method for producing a joined structure according to the present invention includes: a reflow step of heating a first member and a solder material while keeping them in contact with each other in a reflow chamber to melt a solder alloy constituting the solder material, the reflow step including: a first reflow step of melting the solder alloy with an atmosphere in the reflow chamber reduced to a first pressure P.sub.1 lower than the atmospheric pressure; and a second reflow step of, after the first reflow step, melting the solder alloy with the atmosphere in the reflow chamber reduced to a second pressure P.sub.2 lower than the first pressure P.sub.1.

A semiconductor device includes a first die; a second die attached over the first die; a metal enclosure directly contacting and extending between the first die and the second die, wherein the first metal enclosure is continuous and encircles a set of one or more internal interconnects, wherein the first metal enclosure is configured to electrically connect to a first voltage level; and a second metal enclosure directly contacting and extending between the first die and the second die, wherein the second metal enclosure is continuous and encircles the first metal enclosure and is configured to electrically connect to a second voltage level; wherein the first metal enclosure and the second metal enclosure are configured to provide an enclosure capacitance encircling the set of one or more internal interconnects for shielding signals on the set of one or more internal interconnects.

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.

The present disclosure is directed to a compact vertical oven for reflow of solder bumps for backend processes in semiconductor wafer assembly and packaging. This disclosure describes a vertical oven which uses a plurality of wafers (e.g., an example value is 50-100 wafers) in a batch with controlled injection of the reducing agent (e.g. formic acid), resulting in a process largely free of contamination. This disclosure describes controlled formic acid flow through a vertical system using laminar flow technology in a sub-atmospheric pressure environment, which is not currently available in the industry. The efficacy of the process depends on effective formic acid vapor delivery, integrated temperature control during heating and cooling, and careful design of the vapor flow path with exhaust. Zone-dependent reaction dynamics managed by vapor delivery process, two-steps temperature ramp control, and controlled cooling process and formic acid content ensures the effective reaction without any flux.

Disclosed is a method of bonding two copper structures involving compressing a first copper structure with a second copper structure under a stress from 0.1 MPa to 50 MPa and under a temperature of 250 C. or less so that a bonding surface of the first copper structure is bonded to a bonding surface of the second copper structure; at least one of the bonding surface of the first copper structure and the bonding surface of the second copper structure have a layer of nanograins of copper having an average grain size of 5 nm to 500 nm, the layer of the nanograins of copper having a thickness of 10 nm to 10 m.

Provided are a device packing facility and method using DEHT and a device processing apparatus utilizing the DEHT. The device packaging facility includes a mounting unit providing bis(2-ethylhexyl) terephthalate (DEHT) between first and second devices to attach the first and second devices to each other, a processing unit thermally processing the first and second devices that are attached to each other to remove the DEHT and fix the first and second devices to each other, and a transfer unit transferring the first and second devices that are attached to each other from the mounting unit to the processing unit.