Good solderability of PCB pad is critical to make working PCB assembly. Solder joints are often used to make both electronic and mechanical connections. A pad with poor solderability cause cold soldering joints. A cold joint is prone to physical failure and also generally has poor electrical conductivity, which can effect the operation of the circuit or cause total failure.
After manufacturing, two common causes of solderability problems are long storage period and poor storage condition. Many companies try to lower per board cost by ordering in volume. The stockpile may keep boards on the shelf too long. The humidity, exposure to air and temperature cause oxidization to PCB boards. Board oxidation dooms the assembly process before solder even touches the PCB pad.
At KF International PCB Ltd, we provide low-cost just-in-time manufacturing to help you manage the shelf-life of your boards. We also pay particular attention to PCB solderability during the manufacturing process of resist residue cleaning, tinning and packaging.
Taking packaging as an example,all finished board are vacuum packed with bubble wraps and silica gel to reduce board's exposure to air and humidity.This effectively prevents oxidization and surface scratches during transpotation.The following are two images of finished PCB boards manufactured by KF.