10.6 OSP

OSP (which stands for “organic solderability preservative”) is a form of organic tarnish protection that serves as an alternative to metallic surface finishes. At KSG, the ENTEK Plus HT process from MacDermid ENTHONE is used. This forms an organic copper complex at all the copper points on a finished PCB that are not covered with solder mask (i.e., on SMD pads, holes and solder pads). This complex prevents the oxidation of copper by oxygen.
FeatureDescription / Value
Application
  • Soldering
  • Press-fit technology
  • Fine pitch
  • BGAs
Properties
  • Flat soldering surface
  • RoHS compliant
ProcessEntek Plus HT
Plating thickness [µm]0.2 - 0.6
Processing warranty in months
(at a max. storage temperature of 30 °C and max. relative humidity of 70 %)		6

Blog

Soldering surfaces for printed circuit boards, Part 5: Organic Solderability Preservative (OSP)

Frequently asked questions

Does KSG already have an OSP (organic solderability preservative) for multiple soldering operations?
Yes, the only type of OSP we use is ENTEK PLUS HT, which also allows multiple soldering operations.
How many soldering cycles can OSP withstand?
It can be soldered 2 to 3 times (manufacturer does not specify the exact number).
What happens to the OSP layer during the soldering process?
During the placement process, the OSP layer is dissolved by the flux. This exposes the underlying copper layer and allows the solder to bond directly to the copper. Failure to completely remove the OSP layer may result in poor solder wettability or incomplete soldered connections. For this reason, it is important to clean the OSP layer properly prior to soldering to ensure a successful soldered connection.

Keywords

  • Organic solderability preservative (OSP)
  • Multiple soldering cycles
  • Surface finishes
  • Storage and assembly
Next entry:
10.7 Special Surfaces
Go to the next entry