Bottom-surface-metallurgy rework process in ceramic modules

US5722579A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Roy Yu · Wappingers Falls, US
• James Wood · Beacon, US
• Thomas Michael Biruk · Staatsburg, US
• Gregory S. Boettcher · Hopewell Junction, US
• William Brearley · Poughkeepsie, US
• Kimberley A. Kelly · Poughkeepsie, US
• Bouwe W. Leenstra · Walden, US
• Arthur G. Merryman · Hopewell Junction, US

Key dates

• Filing date: Apr 26, 1996
• Grant date: Mar 3, 1998
• Expiry date: Apr 26, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/4853
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Multi-chip modules provided with a pin array may, under close scrutiny, display certain defects that may cause reliability problems. The presence of even one such defect necessitates the scrapping of the module. A method of salvaging the module is described, wherein the module is reworked by the method comprising the steps of applying a shearing force against the pins. During which the module is exposed to a temperature at or above that which is necessary for softening the braze material to remove the pins; polishing the surface of the module including the pads; evaporating the new pads; and attaching new pins to the pads.