Parylene Conformal Coating

Parylene Conformal Coatings

Commonly referred to as parylenes, poly-para-xylylenes are applied at very high temperatures with a vacuum-coating process.  Therefore, they cost significantly more compared to other technologies.

Strengths

• Excellent Uniformity Regardless of Part Geometry - No Pinholes, Fillets, or Bridging
• Chemical Inertness/Barrier Properties Insoluble in Organic Solvents, Acids, or Bases, with Very Low Permeability Rates
• Minimal Added Mass
• Biocompatibility Allows Use in Many Medical Applications
• Low Environmental Impact Process
• Low Outgassing

Weaknesses

Vapor Deposition Polymerization

• Parts are processed by batches in a vacuum chamber, not an in-line process
• Masking required for no-coat areas
• Coating removal and rework generally requires specific equipment, abrasion/micro-blasting most common technique
• Limited UV resistance and operating temperature limit, around 120°C [248°C] in the presence of oxygen
• Cannot be doped