Semiconductor dies having interconnect structures formed thereon, and associated systems and methods, are disclosed herein. In one embodiment, an interconnect structure includes a conductive material electrically coupled to an electrically conductive contact of a semiconductor die. The conductive material includes a first portion vertically aligned with the conductive contact, and a second portion that extends laterally away from the conductive contact. A solder material is disposed on the second portion of the interconnect structure such that the solder material is at least partially laterally offset from the conductive contact of the semiconductor die. In some embodiments, an interconnect structure can further include a containment layer that prevents wicking or other undesirable movement of the solder material during a reflow process.

Semiconductor dies having interconnect structures formed thereon, and associated systems and methods, are disclosed herein. In one embodiment, an interconnect structure includes a conductive material electrically coupled to an electrically conductive contact of a semiconductor die. The conductive material includes a first portion vertically aligned with the conductive contact, and a second portion that extends laterally away from the conductive contact. A solder material is disposed on the second portion of the interconnect structure such that the solder material is at least partially laterally offset from the conductive contact of the semiconductor die. In some embodiments, an interconnect structure can further include a containment layer that prevents wicking or other undesirable movement of the solder material during a reflow process.

Provided is a solder material which enables a growth of an oxide film to be inhibited. A solder ball which is a solder material is composed of a solder layer and a covering layer covering the solder layer. The solder layer is spherical and is composed of a metal material containing an alloy including Sn content of 40% and more. Otherwise the solder layer is composed of a metal material including Sn content of 100%. In the covering layer, a SnO film is formed outside the solder layer, and a SnO.sub.2 film is formed outside the SnO film. A thickness of the covering layer is preferably more than 0 nm and equal to or less than 4.5 nm. Additionally, a yellow chromaticity of the solder ball is preferably equal to or less than 5.7.

Provided is a solder material which enables a growth of an oxide film to be inhibited. A solder ball which is a solder material is composed of a solder layer and a covering layer covering the solder layer. The solder layer is spherical and is composed of a metal material containing an alloy including Sn content of 40% and more. Otherwise the solder layer is composed of a metal material including Sn content of 100%. In the covering layer, a SnO film is formed outside the solder layer, and a SnO.sub.2 film is formed outside the SnO film. A thickness of the covering layer is preferably more than 0 nm and equal to or less than 4.5 nm. Additionally, a yellow chromaticity of the solder ball is preferably equal to or less than 5.7.

The present disclosure relates to use of a stimulus responsive polymer (SRP) as a capping material during direct metal-metal binding. Processes and layers employing an SRP are described herein.

Disclosed is a solder particle including a plastic core; a copper-free metal layer which is formed on an external surface of the plastic core; and a solder layer which is formed on the copper-free metal layer and contains not less than 85 wt % tin. Thus, it is possible to provide a solder particle with a copper-free metal layer, which is excellent in strength and conductivity and prevents or minimizes generation of a void during a reflow process or the like.

Disclosed is a solder particle including a plastic core; a copper-free metal layer which is formed on an external surface of the plastic core; and a solder layer which is formed on the copper-free metal layer and contains not less than 85 wt % tin. Thus, it is possible to provide a solder particle with a copper-free metal layer, which is excellent in strength and conductivity and prevents or minimizes generation of a void during a reflow process or the like.

A technique is disclosed for causing the top surfaces of solder bumps on a chip to be in the same plane to ensure a more reliable bond between the chip and a substrate. The chip is provided with solder pads that may have different heights. A dielectric layer is formed between the solder pads. A relatively thick metal layer is plated over the solder pads. The metal layer is planarized to cause the top surfaces of the metal layer portions over the solder pads to be in the same plane and above the dielectric layer. A substantially uniformly thin layer of solder is deposited over the planarized metal layer portions so that the top surfaces of the solder bumps are substantially in the same plane. The chip is then positioned over a substrate having corresponding metal pads, and the solder is reflowed or ultrasonically bonded to the substrate pads.

A technique is disclosed for causing the top surfaces of solder bumps on a chip to be in the same plane to ensure a more reliable bond between the chip and a substrate. The chip is provided with solder pads that may have different heights. A dielectric layer is formed between the solder pads. A relatively thick metal layer is plated over the solder pads. The metal layer is planarized to cause the top surfaces of the metal layer portions over the solder pads to be in the same plane and above the dielectric layer. A substantially uniformly thin layer of solder is deposited over the planarized metal layer portions so that the top surfaces of the solder bumps are substantially in the same plane. The chip is then positioned over a substrate having corresponding metal pads, and the solder is reflowed or ultrasonically bonded to the substrate pads.

Inter-substrate coupling and alignment using liquid droplets can include electrical and plasmon modalities. For example, a set of droplets can be placed on a bottom substrate. A top substrate can be placed upon the droplets, which uses the droplets to align the substrates. Using the droplets in a capacitive or plasmon coupling modality, information or power can be transferred between the substrates using the droplets.