The full name of OSP is Organic Solderability Preservatives. Also known as Preflux.Simply put OSP is on a clean bare copper surface,To chemical method to grow a layer of organic film. This layer of film with anti-oxidation, thermal shock resistance and moisture resistance .Used to protect the circuit board copper surface in the normal environment no longer oxidation.
In the subsequent high temperature welding, This protective film must be easily removed by the flux quickly. The clean copper surface with the molten solder in a very short period of time to become a solid solder joint.
Degreasing -> secondary washing -> micro etching -> secondary washing -> pickling -> DI washing -> film drying -> DI washing -> drying
The deficiency of the OSP process is that the protective film formed is very thin. It easy to scratch (or scratch), we are must be carefully operated and shipped.
At the same time, OSP film (Refers to the OSP film on the unwelded lands) undergoes discoloration or cracking after repeated high-temperature soldering processes, affecting solderability and reliability.
- Relative humidity: 30 ~ 70%, temperature: 15 ~ 30 ℃, shelf life of less than 6 months。
- OSP PCB should be vacuum-packed and attached to the desiccant and humidity display card.
SMT Manufacturing Requirements:
- In the SMT site unpacking, you must check the humidity display card, and online within 12 hours
- SMT single-sided patch is completed, it must be completed within 24 hours of the second SMT parts SMD assembly
- Complete the SMT after the shortest possible time (up to 36 hours) to complete the DIP manual Insertion