Method of forming a solderable solder deposit on a contact pad

US11032914B2 · kind B2 · utility

Assignee

• Atotech Deutschland GmbH & Co. KG · DE

Inventors

• Kai-Jens Matejat · Berlin, DE
• Sven Lamprecht · Berlin, DE
• Jan SPERLING · Berlin, DE
• Christian Ohde · Berlin, DE

Key dates

• Filing date: Dec 22, 2017
• Grant date: Jun 8, 2021
• Expiry date: Dec 22, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H05K2203/0723
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

A method of forming a solderable solder deposit on a contact pad, comprising the steps of providing an organic, non-conductive substrate which exposes said contact pad under an opening of a first non-conductive resist layer, depositing a conductive layer inside and outside the opening such that an activated surface results, thereby forming an activated opening, electrolytically depositing nickel or nickel alloy into the activated opening such that nickel/nickel alloy is deposited onto the activated surface, electrolytically depositing tin or tin alloy onto the nickel/nickel alloy, with the proviso that the electrolytic deposition of later steps results in an entirely filled activated opening, wherein the entirely filled activated opening is completely filled with said nickel/nickel alloy, or in the entirely filled activated opening the total volume of nickel/nickel alloy is higher than the total volume of tin and tin alloy, based on the total volume of the entirely filled activated opening.