Immersion Tin PCB Surface Finishes and Top 7 Reasons for Their Popularity Analyzed

Immersion Tin PCB Surface Finishes and Top 7 Reasons for Their Popularity Analyzed

Jul 26,2021

The printed circuit boards are small, yet effective components used in several electronic components. Although small, these components possess intricate detailing, which contributes to the current carrying capacity and performance of the electronic circuits where they are used. PCBs possess copper finishes which if not protected properly may lead to deterioration and failure of the circuit. Nowadays, various types of surface finishes are used to protect the copper circuitry, as well as to create a surface that can be soldered for component assembling. Immersion tin is one such surface finish that has gained immense popularity in recent years. This post offers you insights on the benefits of using this surface finish and the importance of sourcing it from the right PCB assembly services provider.

Get Introduced to Immersion Tin Coating

Immersion tin is a metallic coating comprising tin, which is directly deposited on the layer of copper. The tin looks white like silver, which has earned it an alternative name white tin. The deposition of immersion tin is usually done through an electroless chemical bath process. This immersion tin protects the pads and copper pads when they are stored. Unlike other surface finishing, this coating produces a denser uniform layer of 0.8 to 1.2 micrometers. This surface finishing possesses a good lubricity of the hole wall.

Benefits of Immersion Tin PCB

Lead-based surface finishes have been popular for several years. Growing health concerns among users of these PCBs and assemblers have driven PCB assembly services to choose lead-free options. The immersion tin serves as an alternative to lead-based surface finishes. The following features have contributed to their easy acceptance and popularity among PCB manufacturers.

As the advantages of the immersion pin PCB have been well persuaded, you must consider sourcing it from a trusted manufacturer or assembly services provider. This is because if the surface finish fails to make protect the components, there are several chances of PCB failure. This post ends by introducing you to Creative Hi-Tech. The company manufactures and delivers PCBs for use in industrial applications. These PCBs are available in a variety of surface finishes of your choice. You can get in touch with the experts at the company to discuss your requirements for immersion tin PCB.

  • The shelf life of immersion tin coating is six months. Tin and copper possess a strong affinity for each other and form stronger bonds than many other surface finishes. In other surface finishes, the diffusion of metals occurs, which directly affects the shelf life of the finish.
  • Immersion tin coating is easy to rework, unlike other surface finishing. However, the reworking must be only done when necessary.
  • The coating is not expensive, and offers the best value for investment, which makes it a lucrative option for many assemblers looking for effective results at low prices.
  • Immersion tin coating is flat or planar, which makes it perfect for BGA/fine pitch and small component placements. With thicker and complex PCB designs being implemented, this feature offers immense benefits.
  • Great solderability makes immersion tin PCBs immensely popular with assemblers. Although there are several other surface finishes assuring great security, they may limit the solderabilty of the board. This solderability is acquired after several thermal cycles.
  • PCBs suited for backpane panels are mainly assembled using pin insertion in a press-fit way. Immersion tin may not be an appropriate choice if you wish to mount through-hole components.
  • Less chemicals and water is used during the application of immersion tin PCB.
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