Organic Solderability Preservative

Organic Surface Protection (OSP, German organic surface protection ) is a process of construction and connection technology to protect the surface of printed circuit boards during soldering. This layer consists of water-dissolved organic compounds, which selectively bind to copper and protect it for example against oxidation. Thus, PCBs can be stored for several months.

Since the introduction of the RoHS OSP is becoming increasingly important as existing protective coatings are usually lead- based. Also can be achieved especially smooth coatings with OSP as it is not possible with conventional Stay stratifications. A disadvantage, however, is the low heat resistance of OSP coatings, and the resulting inapplicability for multiple configurations. Longer storage is not possible, because of possibly occurring holes formation.