White Spots on the Electronic Assembly

Causes and Solutions for White Residues

White Spots on the Electronic Assembly

If you've ever been involved in assembly cleaning, you might have encountered the issue of "white spots." But what exactly are these spots? Why do they appear white, and where do they come from? More importantly, how can they be resolved? These are common questions, and you'll find the answers right here.

white spots?Multiple Causes with Pragmatic Solutions

When unexpected white spots appear on assemblies without an apparent cause, customers often become perplexed, and their initial assumption is frequently that something must be wrong with the cleaner. However, such instances are exceptionally rare. In the vast majority of cases, other factors are responsible, and the causes can be diverse.

Changes in the assemblies themselves often play a significant role. The use of cheaper materials, reduced development time, or even switching suppliers can introduce new variables. A seemingly more cost-effective option may come with its own drawbacks. If the new components are not compatible with the existing cleaning process, issues can arise, often manifesting as white spots. If reverting to the previous components is not feasible, the only viable solution is often process optimization.

triggerSolder Mask Not Completely Cured

Another common cause of white spots is incomplete curing of the solder mask. In such cases, water from the cleaning process can accumulate within the solder mask material and condense at room temperature, resulting in staining and the appearance of white spots.

A practical and pragmatic solution to address this issue is to use a hot hair dryer. By directing the hot air over the assembly for a certain period, the milky white spots can quickly disappear. The heat helps evaporate the trapped water within the solder mask, restoring the desired appearance of the assembly.

triggerSolder Paste Change

Another frequent cause of white spots on circuit boards is a change in solder paste. When such a change occurs without consulting the cleaning media provider, the cleaner may not be able to effectively remove the new solder paste using the existing system settings. In such cases, it may be necessary to adjust other parameters instead of changing the cleaner itself.

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zestron x-pertiseSolve the Problems with Expertise and Thorough Analysis

Indeed, white spots can arise from various reasons, including factors such as the quality or temperature of the rinse water. However, these issues can be resolved by adjusting the parameters or preparing the rinsing medium accordingly. For instance, modifying the parameters of the rinsing process, such as temperature or flow rate, can help address quality or temperature-related concerns.

In cases where a cleaner has been utilized extensively and is no longer providing the desired outcome, increasing the concentration of the cleaner can sometimes yield the desired result once again. By adjusting the concentration, it is possible to enhance the cleaning efficacy and overcome any limitations that may have arisen due to prolonged usage.

YOU CAN TRUST IN THISWe Provide Customized Solutions for Every Situation

In general, optimizing the cleaning process can resolve most cases where complications arise due to white spots. Through careful evaluation and adjustment of cleaning parameters, customers can often overcome the issue.

If a satisfactory solution cannot be achieved through process optimization, our Application Engineers are readily available to assist and working closely with customers to identify the root causes and develop tailored solutions.