Patent · US Active

Manufacture of coated copper pillars

US9331040B2 · kind B2 · utility

2Cited by

0References

20Claims

0Family size

Assignee

Atotech Deutschland GmbH & Co. KG · DE

Inventors

Thomas Beck · Catonsville, US
Gerhard Steinberger · Berlin, DE
Andreas Walter · Egloffstein, DE

Key dates

Filing date	Jul 19, 2013
Grant date	May 3, 2016
Priority date	—
Expiry date	Jul 19, 2033

Classification

Technology area (CPC H)Electricity
CPC primaryH01L2924/3841
WIPO fieldSemiconductors
WIPO sectorElectrical engineering

Abstract

The present invention relates to a method for forming a copper pillar on a semiconducting substrate, the copper pillar having an underbump metallization area comprising a metal less noble than copper and optionally a solder bump on the top portion, and having a layer of a second metal selected from tin, tin alloys, silver, and silver alloys deposited onto the side walls of said copper pillar. A layer of a first metal which is more noble than copper is deposited onto the entire outer surface of the copper pillar prior to deposition of the second metal layer. The layer of a second metal then has at least a reduced number of undesired pin-holes and serves as a protection layer for the underlying copper pillar.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.