Process, parylene coater, parylene deposition, parylene coating, parylene coating process

Deposition Process

Vapor Deposition

Parylene is an ultra-conformal, thin film polymer coating suited to a multitude of industries and applications due to its outstanding barrier protection, electrical insulation properties, and its biostable and biocompatible nature.


Before we begin the parylene coating process we take important steps to ensure success. Upon arrival at VSI, we perform an Incoming inspection to check for part accuracy and cleanliness.

After incoming inspection, customer parts are processed through an essential adhesion promotion step to ensure parylene adheres to the part substrate.

Any areas that must remain free of parylene are sealed prior to the deposition process and the parts are fixtured into the vacuum deposition chamber.

Coating Process

With the parts fixtured in the chamber, the deposition process can begin.  Parylene is deposited via chemical vapor deposition (CVD) at micron level thicknesses (typically 1-50 microns).


Parylene is applied using a three-stage vapor deposition process, which is illustrated above.

Stage 1: The solid parylene dimer – in powder form – is placed inside the vaporizer where the parylene is vaporized into a dimer gas at 150 degrees C.

Stage 2: The dimer gas then flows into the pyrolysis furnace which, at 690 degrees C, heats the dimer gas into a monomer vapor.

Stage 3: Finally, the monomer vapor enters the room-temperature coating chamber, where the parylene deposits itself molecule-by-molecule onto everything in the chamber to create a very thin and truly conformal coating.


After the parylene deposition process is completed, parts are removed and we verify the thickness by taking sample thickness measurements throughout the chamber.

After thickness verification, parts are carefully handled to expose uncoated areas as required.  Next, parts are inspected to ensure they meet customer specifications, then packaged and labeled for shipping.  Finally, coated parts along with VSI quality documentation are shipped to the customer’s facility ready for use.

Ask an Expert about your own application and let us impress you! Because each customer’s part is unique, our engineers bring their extensive experience to ensure that every part is coated to your unique specifications.  For products requiring innovative solutions, there is no better choice than VSI Parylene.