Electroplated indium bump stacks for cryogenic electronics

• Main Authors: Cantaloube, Christopher, Rouse, Richard P
• Format: Patent
• Language: English
• Published: 02.01.2024
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

A cryogenic under bump metallization (UBM) stack includes an adhesion and barrier layer and a conductive pillar on the adhesion and barrier layer. The conductive pillar functions as a solder wetting layer of the UBM stack and has a thickness. An indium superconducting solder bump is on the conductiv...