Title :
Correlation of solderability failures of tin-plated parts with dissolved metal build-up in preclean bath
Author :
Trabado, Flordeliza L. ; Ratilla, Eva Marie
Author_Institution :
Intel Philippines Manuf. Inc., Makati Metro Manila, Philippines
Abstract :
Evaluation of preclean baths that resulted in high solderability failures of tin plated parts revealed that specific gravity measurement and acid-base titration of sulfuric acid (H2SO4) are still insufficient to assess the effectiveness of the acid in etching the base metal. Ion chromatography analysis of dissolved metal buildup in preclean bath indicated levels of iron (Fe3+) and nickel (Ni2+) at 250 p.p.m. and 135 p.p.m., respectively. Beyond this point the solderability problem as assessed by the wetting balance begins. The use of the wetting balance method is being recommended to supplement the current dip and look method. Wetting balance is a quantitative test and it can therefore give information useful in estimating the defect location and identifying the source of the problem
Keywords :
electronic equipment manufacture; electroplating; etching; soldering; surface treatment; acid-base titration; defect location; dip and look method; dissolved metal build-up; etching; ion chromatography analysis; preclean bath; solderability failures; specific gravity measurement; wetting balance; Etching; Gravity measurement; Iron; Lead; Manufacturing; Surface contamination; Temperature; Testing; Tin; Transducers;
Conference_Titel :
Electronic Components and Technology Conference, 1992. Proceedings., 42nd
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-0167-6
DOI :
10.1109/ECTC.1992.204185
