Parylene C, a chlorinated poly(para-xylylene) polymer, is widely employed as a biocompatible, corrosion-resistant coating, as a packaging material, and as an optically transparent material. Parylene conformal coatings are ultra-thin, pinhole-free polymer coatings that provide a number of high-value surface treatment properties such as excellent moisture, chemical and dielectric barrier properties, thermal and UV stability, and dry-film lubricity. These properties make Parylene coatings the ideal choice for a number of applications throughout the medical device, electronics, transportation, defense and aerospace industries.
Similar to other polymers, parylene can be etched isotropically with an O2 plasma.
- Plasmatherm 790
- LAM 9400
- STS Glass Etcher
- YES Plasma Stripper
- Deep UV SenLights PL16
- Common uses of Parylene C are
- RIE Etch
- Parylene etches are O2 based and etch photoresits at a similar rates.
- Hard masks of Aluminum or Silicon dioxide are often used.
a)Schematic that shows the static contact angles b) Photograph of a water droplet on a Parylene C film.
As with other polymers, the hydrophilicity of the surface can be changed by exposing the sample to an oxygen plasma 
Below a list of useful information when considering the use of Parylene, taken from Diamond-mf.com
- Room temperature formation means the coatings are effectively stress-free
- Parylene is chemically and biologically inert and stable and make excellent barrier material.
- Parylene has excellent electrical properties: low dielectric constant and loss with good high-frequency properties; good dielectric strength; and high bulk and surface resistance.
- Parylene has good thermal endurance: Parylene C performs in air without significant loss of physical properties for 10 years at 80°C and in the absence of oxygen to temperatures in excess of 200°C.
- Parylene is optically transparent and can be used to coat optical elements.
- FDA approved material
- Parylene coating has excellent mechanical properties, including high tensile strength.
- Parylene is stable over a very wide temperature range (-200 ‘C to +200 ‘C), allowing the chamber items coated in Parylene to be put in an autoclave
- Parylene is unaffected by solvents
For complete information on Parylene C physical properties see: Parylene C TDS
Parylene C thin film FTIR Spectrum from reference above.