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Parylene Conformal Coatings - Parylene Conformality Explained


Parylene (p-polyxylylene) conformal coatings are unique due to their capacity to be polymerized and deposited by the chemical vapor deposition (CVD) method onto surfaces near room temperature. As a result of this process, pinhole-free, high-purity, extremely thin coatings are formed out of dimer materials.

Regarding conforming to complex or unusual surfaces, Parylene is one of the best polymer coatings for moisture resistance. This attribute and the fact that Parylene is a stable chemical compound that creates an excellent barrier make it the optimal choice where resilient electronic products are a mandate. But why is Parylene coating conformal?

Download HZO’s Parylene datasheet to learn more about Parylene’s properties

 

Why is Parylene Coating Conformal?

Liquid coatings with application methods such as dipping, brushing, or spraying may cause the coatings to exhibit meniscus forces or pull away from edges, which does not occur with Paylene deposition. With CVD, the coating penetrates around and beneath closely spaced components with consistent, uniform buildup, allowing for substantial physical and electrical protection with a substantially thinner layer than conventional coatings.

 

Parylene Deposition Process

Thus, the Parylene coating process explains why Parylene is so conformal. You can read an in-depth description of the CVD process versus PECVD in our blog on the subject; below are some general benefits of CVD:

Download a visual explanation of the process

 

  • CVD produces coatings with complete coverage even around and beneath closely spaced chips and wires.
  • CVD deposits Parylene molecule by molecule onto substrates with precision and control.
  • The Parylene deposition process requires no catalyst, hardener, or heat curing.
  • Polymerization does not release harmful by-products, as with other conformal coatings.

Chemical vapor deposition process

 

When Parylene polymers are deposited from the vapor phase with the CVD process, all sides of a component are impinged by the gaseous monomer and uniformly coated. This feature of the process is responsible for why Parylene coating is conformal.

 

Importance of Conformality and Uniformity

Truly conformal coverage occurs when a film precisely follows the coated component’s geometry. Conformality allows for the optimization of surface properties regardless of the shape of the part and ensures that microdevice properties such as conductance do not vary due to significant variations in thickness. Uniform thickness is critical to prevent proper reinforcement against degradation and wear.

 

Parylene Conformality Compared to Liquid Coatings

 

Parylene conformality

 

Along with performance concerns, achieving uniformity improves production factors such as yield rates and repeatability. With the chemical vapor deposition process, engineers have confidence that there will not be thickness fluctuations from product to product and that specs are being met. By ensuring optimum coating deposition performance is met, you can lower your total cost of ownership by keeping your repeatability and yield on target.

 

Parylene Conformal Coating Service with HZO

However, although a process may achieve repeatable, uniform thickness distributions, this does not mean it is viable for your company – uptime and upfront costs must also be considered. Parylene has traditionally only been used for mission-critical applications such as medical products. HZO, a turnkey CVD process provider, has made Parylene and its application feasible for most industries for years. Our engineers have crafted capital coating equipment that addresses upfront cost concerns and makes Parylene scalable. If you are interested in the powerful barrier properties of Parylene films and the benefits of its vacuum deposition process, reach out today to speak to one of our engineers.

Additional Resources

Download the HZO Parylene Datasheet
Datasheet

Download the HZO Parylene Datasheet

Learn About Corrosion Resistance From An Industry-Leading Engineer
Webinar

Learn About Corrosion Resistance From An Industry-Leading Engineer

Learn About HZO Coatings With Our Resource Page
Resource

Learn About HZO Coatings With Our Resource Page

Learn About the Parylene Process With Our Resource Page
Resource

Learn About the Parylene Process With Our Resource Page

Learn About Parylene Properties With Our Resource Page
Resource

Learn About Parylene Properties With Our Resource Page

Parylene Thickness - How Much is Enough?
Blog

Parylene Thickness - How Much is Enough?

Understand Parylene Masking
Blog

Understand Parylene Masking

Learn How to Remove Parylene Coating
Blog

Learn How to Remove Parylene Coating

Is Parylene Right For Your Project?
Blog

Is Parylene Right For Your Project?

How HZO Makes Parylene Scalable
Blog

How HZO Makes Parylene Scalable

Learn about Protective Coating Methodologies With Our White Paper
Technical Paper

Learn about Protective Coating Methodologies With Our White Paper

The Illustrated Guide to CVD
Infographic

The Illustrated Guide to CVD

Learn How To Incorporate Conformal Coating Into Your Manufacturing Process
Webinar

Learn How To Incorporate Conformal Coating Into Your Manufacturing Process

Parylene Coating for Reliable Product Design Webinar
Webinar

Parylene Coating for Reliable Product Design Webinar

Download the HZO Parylene SDS
Datasheet

Download the HZO Parylene SDS

Learn How to Bring Parylene Deposition In-House
Technical Paper

Learn How to Bring Parylene Deposition In-House

Coating Complex Geometries Video
Video

Coating Complex Geometries Video

Overcoming Parylene Coating Challenges Video
Video

Overcoming Parylene Coating Challenges Video