Techniques

The UC Davis Facility for Interconnect Technology is equipped for bonding and testing various types of interconnect technology. Mainly, we investigate gold stud bump bonding, anisotropic conductive film (ACF), various types of solder balls, indium studs, various types of interposers, and solder paste.

Gold Studs

The FIT team at UC Davis researches several types of gold stud bump bonding techniques, including single 1 mil gold studs, 0.5 mil gold studs, and double gold studs.

  • Single 1 mil studs are currently the industry standard for bump bonding. We have verified that our single gold stud bonding technique consistantly produces bonds with >1mΩ resistance.
  • Single 0.5 mil Studs have the potential to greatly decrease the minimum bonding pitch gold bump bonding.
  • Double Gold Studs have shown to require less bonding pressure and a lower bonding heat than conventional 1 mil gold studs. This is useful for bonding delicate chips with less damage.

ACF

Anisotropic Conductive Film is currently being investigated as a novel alternative to conventional bump bonding techniques. It would allow manufacturers to bond large surface areas relatively quickly.

Solder

Solder balls are a reliable form of bonding that allows the researcher/manufacturer to control the temperature and other characteristics of the bond. SnPb solder is being used to bond the for KPiX ILC Electromagnetic Calorimeter project.

Indium

Indium allows the bonder to cold weld chips together with low force.