Method for ablating points of contact (debumping)

US7481352B2 · kind B2 · utility

Assignee

• Pac Tech—Packaging Technologies Gmbh · DE

Inventors

• Thorsten Teutsch · Berlin, DE
• Elke Zakel · Falkensee, DE

Key dates

• Filing date: Oct 5, 2001
• Grant date: Jan 27, 2009
• Expiry date: Oct 5, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H05K2203/0776
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

The invention relates to a method for removing a plurality of raised places of contact made of a meltable metal, such as tin or indium or an alloy, such as tin-containing solder, silver-containing solder or lead-containing solder, the meltable metal being meltable above a first temperature limit, the places of contact being surface-distributed over a substrate. It is also possible to form vaulted domes on a plurality of metallic support segments which are located on one of the surfaces of a substrate. The invention aims at reducing production costs, particularly at removing a soldered layer once applied. If defective contact places occur, a plurality of the raised contact places, particularly substantially all contacts, are at least in substantial portions melted off from the substrate by contacting them with a molten metal. Between the substrate and the support segments distributed over the substrate and a surface of the molten metal an organic fluid may be present, the organic fluid being provided as a covering layer only and evaporating off the substrate surface, after the vaulted domes have been formed.