BENCHMARK STUDY: pH-NEUTRAL VS. ALKALINE CLEANING AGENTS
Authors: Harald Wack, Ph.D., Umut Tosun, M.S.; John Neidermann; John Radmann Company: ZESTRON America; Speedline Technologies; Trace Laboratories Date Published: 10/24/2010
Abstract: In recent years, significant changes in solder paste formulations and assembly processes have occurred. Post reflow residues of tin-lead and newer lead-free soldering materials are more difficult to remove due to increases in component density, larger component packages, higher lead counts, finer lead spacing and lower standoff distances. While modern aqueous alkaline cleaning agents effectively remove these flux residues, achieving satisfactory results often requires an increase in temperature, exposure time, chemical concentration, and mechanical energy. This often presents a new set of challenges in the area of material compatibility.