Patent ID: 11862593
Assignee: MICROSOFT TECHNOLOGY LICENSING, LLC
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A cryogenic under bump metallization (UBM) stack, comprising:
a bond pad;
an adhesion and barrier layer formed on the bond pad;
a conductive pillar on the adhesion and barrier layer, the conductive pillar configured to function as a solder wetting layer of the UBM stack and having a thickness; and
an indium superconducting solder bump on the conductive pillar, the thickness of the conductive pillar being sufficient to prevent intermetallic regions in the conductive pillar that form due to interdiffusion between the conductive pillar and the indium superconducting solder bump during heat treatments and storage at room temperature from extending through the thickness of the conductive pillar.