The Adverse Effects of Fingerprints on SMT Assembly Processing

During the assembly process, despite our utmost efforts to avoid it, fingers often inadvertently touch the circuit board. These seemingly insignificant fingerprints can actually have significant adverse effects on SMT assembly processing. Here, Charmhigh Electromechanical will discuss the adverse effects of fingerprints on SMT assembly processing, inviting interested parties to learn more about it.

First, when bare hands directly touch a circuit board that has not undergone solder mask treatment, the fingerprints can lead to poor adhesion of the green solder mask layer. During the hot air leveling process, these poorly adhered green solder masks are prone to bubbling and peeling, affecting the overall quality of the circuit board.

Second, the oil and sweat in fingers can react chemically with the copper surface of the circuit board within a very short time, causing oxidation of the copper surface. This oxidation phenomenon results in distinct fingerprint marks after plating, not only affecting the smoothness of the coating but also causing significant adverse effects on the appearance of the product.

Third, during the preparation stage before wet film printing, screen printing, or lamination, if the circuit board surface is contaminated with the oil and grease left by fingerprints, it will significantly reduce the adhesion between the dry/wet film and the circuit board. During the plating process, insufficient adhesion may lead to penetration plating and coating separation, while in the gold plate production process, it may cause patterns to appear on the board surface. After the completion of solder mask production, these oils and greases may also cause oxidation of the board surface, resulting in a color difference between the sunny and shady sides, affecting the overall appearance.

Fourth, during the process from solder mask application to packaging for gold boards, any contact with bare hands can lead to uncleanliness of the board surface, thereby affecting its solderability or bonding effect. Therefore, maintaining the cleanliness of the circuit board and avoiding contact with bare hands is crucial throughout the entire SMT assembly process.

Hunan Charmhigh Electromechanical is a professional manufacturer of SMT placement machines. If you have a need to purchase SMT placement machines, please contact us, and we will provide you with efficient and professional services. If you wish to become our local dealer, we will offer you mutually beneficial and win-win agency solutions.WhatsApp : +8618100733752 / WeChat : 86 18100733752 / Skype : 86 18100733752