Patent · US Expired

Non-destructive low melt test for off-composition solder

US6016947A · kind A · utility

3Cited by
8References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 21, 1997
Grant dateJan 25, 2000
Priority date
Expiry dateOct 21, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K2203/163
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A non-destructive method for identifying off-composition solder columns of for example, a ceramic column grid array. The method is performed at the ceramic module level prior to card assembly to avoid costly loss or rework post card assembly. The assembly of solder columns on a substrate is heated to a temperature below the melting temperature of pure-composition solder and above the temperature of attachment of a solder column to an organic board. Heating the assembly produces visually detectable changes characteristic of off-composition solder which are used for identifying which solder columns are composed of off-composition solder.

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