Designers must keep costs in mind when designing a project.
In the world of conformal coating, that means finding ways to get the best protection for your device at the lowest cost.
Knowing that, if you’re working on a Parylene project, it’s important to fully understand the 5 elements that go into Parylene pricing. Approaching each area correctly will help you achieve the lowest possible cost for your project:
- Raw materials
- Lot sizes
1. Labor Costs for Parylene
In many cases, the biggest cost of a coating project is manual labor. Tasks such as cleaning, masking, and inspection take time. They must also be performed by a well-trained technician.
There are two ways to minimize your labor costs.
First, the old saying, "measure twice, cut once" applies with a Parylene coating project. Mistakes in the planning stage can often lead to costly, time-consuming repairs. It's important that you clearly document exactly what you want to happen. The last thing you want is a communication error that leads to a problem during the application process.
Second, ensure you have competent, well-trained technicians working on the project. Mistakes with Parylene lead to time-consuming, expensive repair work. This repair work can often be the single biggest unexpected cost for a Parylene coating project.
2. Raw Material Costs for Parylene
Parylene dimer is the raw, solid form of Parylene. During the application process, the dimer will be vaporized and then pulled into a vacuum chamber. The gas molecules will deposit evenly on any object inside the chamber, creating a thin, protective Parylene layer on the objects.
Some Parylene dimer types cost as low as $200 per pound. There are also specialized forms of Parylene that can be as expensive as $5,000 a pound.
To minimize material costs, consult with a Parylene expert as early as you can in your design process. By working with an expert, you can be sure you're not paying for specialized materials unless you actually need them.
3. Adhesion for Parylene
Parylene can coat almost anything.
Its unique features allow it to be used effectively on a diverse range of materials, including metal, ceramic, paper, plastic, ferrite, resin and silicon.
Parylene can be made to conform to any shape, including sharp edges, crevices, points, flat and exposed internal surfaces. Parylene works under pressures, stresses and in environments that would be detrimental to other types of coatings.
Despite Parylene’s versatility, some materials will still need a bit of preparation to ensure the Parylene properly adheres to the device being coated. The most common surface modification method to improve parylene adhesion is the use of A-174 silane.
A-174 silane is usually applied after the masking operation. Technicians will apply the material either by a manual spray, soaking, or a vapor phase silane process. The silane molecules form a chemical bond with the surface of the device. This, in turn, provides a surface Parylene can easily adhere to.
The way to minimize adhesion costs is to prepare the device correctly the first time. Poor adhesion due to poor device preparation can be another cause for expensive rework and repair.
4. Parylene Lot Sizes
The vacuum chambers used for Parylene coating have a fixed size. This means one batch of Parylene can only coat as many items as can fit in a single chamber. The chambers we use at Diamond-MT range from 11" by 11" up to 16" by 31", although larger chambers do exist.
To optimize costs, work with your coating provider to get as many items inside the deposition chamber as possible at a given time.
5. Time to Complete a Parylene Batch Run
One "run" of Parylene takes anywhere from a few hours to over a day. However, the preparation for a Parylene coating project begins weeks or months before the application.
Most coating providers will have a standard, explicit set of processes they use for customer orders. For the best results and lowest costs, let the providers use their standard process with your devices.
If you ask for a rush on a project, you risk introducing errors. Your coating provider might also charge a rush fee for orders on a tight timeline.
The No. 1 Thing You Can Do to Prevent Runaway Costs in Parylene Coating
The No. 1 way to keep your costs in line when carrying out a Parylene coating project is to avoid mistakes in the first place. The importance of properly preparing your device for Parylene coating success cannot be stressed enough.
As always, the most effective way to prevent coating failures is to ensure you’re working with an experienced coating provider.
Experienced technicians will know how to apply a wide variety of coatings, without causing any of the problems we’ve discussed in this article. And they’ll know how to complete your project at the best possible cost for you and for your company.