PCB News - Advantages and disadvantages of tin spraying process in PCB

Advantages and disadvantages of tin spraying process in PCB

In PCB proofing, tin spray board is a common type of PCB board, which is widely used in various electronic equipment, communication products, computers, medical equipment, aerospace and other fields and products.

So, what are the advantages and disadvantages of the spray tin plate? Let me explain in detail for you below.

Tin spraying is a step and process in the PCB proofing process. The PCB board is immersed in the molten solder pool, so that all exposed copper surfaces will be covered by solder, and then the excess solder on the board is removed by a hot air cutter. remove. The soldering strength and reliability of the circuit board after tin spraying are better. However, due to its process characteristics, the surface flatness of the tin-spraying process is not good, especially for small electronic components such as BGA package types, due to the small soldering area, if the flatness is not good, it may cause problems such as short circuits.

advantage:
1. The wettability is better during the soldering process of the components, and the soldering is easier.
2. It can prevent the exposed copper surface from being corroded or oxidized.

shortcoming:
It is not suitable for soldering pins with fine gaps and components that are too small, because the surface flatness of the spray tin plate is poor. Tin beads are easy to produce in PCB proofing, and it is easier to short-circuit the components with fine-gap pins. When used in the double-sided SMT process, because the second side has undergone a high-temperature reflow soldering, it is very easy to spray tin and re-melt, resulting in tin beads or similar droplets that are affected by gravity into spherical tin dots, which make the surface even worse. Flattening affects welding problems.
At present, some PCB proofing uses OSP process and immersion gold process to replace the tin spraying process; technological developments have also led some factories to adopt the sinking tin and silver immersion process. In addition to the lead-free trend in recent years, the use of the tin spraying process has been further limit. ipcb is a high-precision, high-quality PCB manufacturer, such as: isola 370hr PCB, high-frequency PCB, high-speed PCB, ic substrate, ic test board, impedance PCB, HDI PCB, Rigid-Flex PCB, buried blind PCB, advanced PCB, microwave PCB, telfon PCB and other ipcb are good at PCB manufacturing.