Parylene Coating Removal can be broken down into three categories for removal of parylene coating:
1) Thermal: The thermal parylene coating removal technique (including using a soldering iron to burn through the conformal coating) is the least recommended technique of coating removal. Most conformal coatings require a very high temperature and/or long exposure times. This, in turn, can cause discoloration, leave residues, and adversely effect solders and/or other materials used in the construction of the board from boards. Also, temperature-sensitive components may be damaged. Extreme caution must be taken when burning through conformal coating because some coatings emit very toxic vapors that are hazardous to the people doing the stripping and those around them.
2) Mechanical: Mechanical removal techniques include cutting, picking, sanding or scraping the area of parylene coating to be removed. However, most types of parylene coatings are very tough to remove using this method making the probability of damage to the board very high.
3) Abrasion: The micro abrasive blasting technique offers a fast, cost-effective, easy to control and environmentally friendly non-solvent based method to remove conformal coatings. The system can remove parylene conformal coatings from a single test node, an axial leaded component, a through-hole integrated circuit (IC), a surface mount component (SMC) or an entire printed circuit board (PCB).In the micro abrasive blasting process, a precise mixture of dry air or an inert gas and an abrasive media is propelled through a tiny nozzle attached to a stylus which is either handheld or mounted on an automated system. This allows the mixture to be pinpointed at the target area of the parylene coating to be removed. A vacuum system continuously removes the used materials and channels them through a filtration system for disposal. The process is conducted within an enclosed anti-static chamber and features grounding devices to dissipate electrostatic potential.
To learn more about the parylene removal process and to learn how you can get started with Diamond MT, please contact us today!