Embodiments herein may relate to an apparatus with a ball grid array (BGA) package that includes a plurality of solder balls of an off-eutectic material. In embodiments, the respective solder balls of the plurality of solder balls may form solder joints between a substrate of the BGA and a second substrate. In some embodiments the joints may be less than approximately 0.6 micrometers from one another. Other embodiments may be described and/or claimed.

A method of forming a stacked surface arrangement for semiconductor devices includes joining a first surface to a second surface with a solder bump, the solder bump including a substantially pure first metal; depositing nanoparticles of a second metal onto a surface of the solder bump; performing an annealing operation to form a film of the second metal on the surface of the solder bump; and performing a reflow or a second annealing operation to transform the solder bump from the substantially pure first metal to an alloy of the first metal and the second metal.

A method of forming a stacked surface arrangement for semiconductor devices includes joining a first surface to a second surface with a solder bump, the solder bump including a substantially pure first metal; depositing nanoparticles of a second metal onto a surface of the solder bump; performing an annealing operation to form a film of the second metal on the surface of the solder bump; and performing a reflow or a second annealing operation to transform the solder bump from the substantially pure first metal to an alloy of the first metal and the second metal.

A packaging structure includes a first substrate including a first metal terminal and a second metal terminal whose height is lower than the height of the first metal terminal; and a second substrate including a third metal terminal and a fourth metal terminal whose height is lower than the height of the third metal terminal, the second substrate being provided on the first substrate, the first metal terminal and the third metal terminal being directly bonded with each other, and the second metal terminal and the fourth metal terminal being bonded via a connection portion.

A packaging structure includes a first substrate including a first metal terminal and a second metal terminal whose height is lower than the height of the first metal terminal; and a second substrate including a third metal terminal and a fourth metal terminal whose height is lower than the height of the third metal terminal, the second substrate being provided on the first substrate, the first metal terminal and the third metal terminal being directly bonded with each other, and the second metal terminal and the fourth metal terminal being bonded via a connection portion.

A method of assembling a flipchip semiconductor package, includes placing a semiconductor die having circuitry electrically coupled to bond pads with bumps having solder paste thereon onto bonding features of a package substrate. Arc welding is used using an arc welding apparatus including a biased electrode having a tip spaced apart from the solder paste, wherein electrical current generated by the arc welding melts the solder paste to provide a solder connection.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

Methods and systems for low-force, low-temperature thermocompression bonding. The present application teaches new methods and structures for three-dimensional integrated circuits, in which cold thermocompression bonding is used to provide reliable bonding. To achieve this, reduction and passivation steps are preferably both used to reduce native oxide on the contact metals and to prevent reformation of native oxide, preferably using atmospheric plasma treatments. Preferably the physical compression height of the elements is set to be only enough to reliably achieve at least some compression of each bonding element pair, compensating for any lack of flatness. Preferably the thermocompression bonding is performed well below the melting point. This not only avoids the deformation of lower levels which is induced by reflow techniques, but also provides a steep relation of force versus z-axis travel, so that a drastically-increasing resistance to compression helps to regulate the degree of thermocompression.

A method includes picking up a first package component, removing an oxide layer on an electrical connector of the first package component, placing the first package component on a second package component after the oxide layer is removed, and bonding the first package component to the second package component.