Removing solder from integrated circuits for failure analysis
US6083848A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1998 |
| Grant date | Jul 4, 2000 |
| Priority date | — |
| Expiry date | Mar 31, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/2851
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for removing solder from the leads of ICs including immersing the IC in an acid solution. The acid solution dissolves the excess solder on the IC leads. The acid solution is preferably a hydrogen chloride solution containing about 38% hydrogen chloride and 62% water. The acid solution, however, can contain up to 50% hydrogen chloride. After the IC is immersed for a period of time, preferably ten minutes, it is removed from the acid solution and rinsed with water. The IC is rinsed so as to remove any remaining acid solution residue. Rinsing for 5 minutes or more typically ensures removing all of the acid solution. The IC is then inspected to determine whether substantially all of the excess solder is removed from the IC leads. If excess solder still remains on the IC leads, the IC is reintroduced into the solder removing process including immersing the IC in the acid solution, rinsing the IC with water, and inspecting the IC. The process is repeated until substantially all, if not all, of the excess solder is removed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.