Stress-reduced Ni-P/Pd stacks for bondable wafer surfaces

US8986789B2 · kind B2 · utility

Assignee

• Atotech Deutschland GmbH & Co. KG · DE

Inventors

• Albrecht Uhlig · Berlin, DE
• Josef Gaida · Berlin, DE
• Christof Suchentrunk · Berlin, DE
• Michael Gerald Boyle · Rock Hill, US
• Brian Washo · Fort Mill, US

Key dates

• Filing date: Oct 1, 2009
• Grant date: Mar 24, 2015
• Expiry date: Apr 13, 2032

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/12889
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

The invention relates to a substrate having a bondable metal coating comprising, in this order, on an Al or Cu surface: (a) a Ni—P layer, (b) a Pd layer and, optionally, (c) an Au layer, wherein the thickness of the Ni—P layer (a) is 0.2 to 10 m, the thickness of the Pd layer (b) is 0.05 to 1.0 m and the thickness of the optional Au layer (c) is 0.01 to 0.5 m, and wherein the Ni—P layer (a) has a P content of 10.5 to 14 wt.-%. The deposit internal stress of the resulting Ni—P/Pd stack is not higher than 34.48M−Pa (5,000 psi). Further, a process for the preparation of such a substrate is described.