Parylene is among the strongest, safest, and most reliable conformal coatings. It can coat surfaces of many sizes and shapes, all while performing under even the most extreme conditions. Naturally, this is excellent while the coating is doing its job--but how do you remove something designed to be so strong and permanent? Today we'll cover parylene removal, which techniques to avoid, and what you need to know.
Removing a Conformal Coating
There are many reasons why conformal coating removal may be necessary. Perhaps it was applied incorrectly, or the specifications of the job changed; regardless, it is crucial to approach this task both safely and efficiently to protect the composition of the substrate material or device. This is especially true of parylene coating, which tends to be slightly more particular when it comes to specific removal techniques.
For example, many conformal coatings can be removed chemically--especially acrylic, epoxy, and silicone coatings. Chemical parylene removal, however, is not recommended. While tetrahydrofuran (THF) can be used under certain circumstances, it is often necessary to consider alternative removal techniques.
Here are a few recommended approaches to parylene removal:
If you're looking to remove small, specific areas of parylene--generally called "spot removal"--then thermal removal is likely the best approach. It is less reliable over large surfaces but can be effective and efficient for certain jobs.
Plasma application can be an effective parylene removal technique. The specifics depend on the type of parylene; for example, plasma reacts differently with Parylene N than Parylene C. With appropriate research, this method is fast, safe, and efficient.
For large areas of parylene coating, the fastest and easiest technique is often abrasion removal. It is especially favored for its precise results, leaving a clean, smooth surface for conformal coating reapplication.
Want to learn more about conformal coatings? Need to research parylene removal? We're here to help.