Organic solderability preservative (OSP) coatings are among the leading surface finish options in lead-free soldering because of their excellent solderability, ease of processing, and low cost. This article uses Gas Chroma-tography-Mass Spectroscopy (GC/MS), Thermogravimetric Analysis (TGA), and X-ray Photoelectron Spectroscopy (XPS) to characterize the relative thermal properties of a novel high temperature (HT) resistant OSP coating. The GC work performed in this study shows the key components in the HT OSP coating that affect solderability. The GC work also shows the alkyl benzimidazole-HT used in HT OSP has the lowest volatility. The TGA data also illustrates that the HT OSP coatings have a higher decomposition temperature compared to existing industry standard OSP coatings. The XPS shows that HT OSP has only about 1% increase of oxygen content after five lead-free reflow cycles. These improvements are then related to the industry's challenges of lead free soldering.
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