Title: A Correlation Study on Extract Solutions and Ionic Residues
Author: Charmaine Johnson and Doug Pauls, Rockwell Collins
Abstract:
The world’s electronics industry has long used resistivity of solvent extract (ROSE) testing to
assess ionic residues on printed boards, both for process control and for product acceptance.
As portions of the industry transition to the more accurate and illuminating ion
chromatography methods for ionic assessment, various extraction methodologies exist which
yield different results. Some methods use 10% isopropanol / 90% deionized water; some use
50% isopropanol / 50% deionized water; and some use 75% isopropanol / 25% deionized water.
This paper covers a study performed on unpopulated (bare) printed boards, extracting samples
in the three different extract solutions, and analyzing by ion chromatography. Results are
compared to classic ROSE test methods.