This leaves the solder oxide-free and in its pure form. As temperatures raise to above 200C, the formate salts decompose to water, hydrogen, and CO2.During the soak phase of a thermal profile (between ~ 150C and 200C), formic acid vapor is introduced into the process chamber where it reacts with the metal oxides on the solder and creates formate salts.The chemistry involved with formic acid reflow is a two-step process: How Does Formic Acid Reflow Work for fluxless soldering? Heller Industries was the first company to bring continuous operation fluxless reflow to market.Process steps related to flux, such as for pre-reflow fluxing and post-reflow flux cleanup steps are no longer needed, saving time, money, and floor space.Eliminates issues related to residual flux, such as voiding.Fluxless reflow utilizes Formic Acid (CH2O2) vapor to act as a reducing agent to oxides on metal solder, replacing the need for flux.This results in underfill voids and causes reduced reliability For flip chip and BGA applications, flux residue has the potential be trapped between interconnects, blocking underfill flow.If not cleaned properly flux residue can become acidic and diminish the reliability of the device. Flux leaves behind a residue which needs to be cleaned post reflow.Flux can outgas during the reflow process creating solder voids.Flux helps to remove oxides from the metals being solder, improving the overall wettability of solder needed for high quality solder joints. ![]() Traditionally, using flux was a necessary part of soldering.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |