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A single-beam plasma source was developed and used to deposit hydrogenated amorphous carbon (a-C:H) thin films at room temperature. The plasma source was excited by a combined radio frequency and direct current power, which resulted in tunable ion energy over a wide range. The plasma source could effectively dissociate the source hydrocarbon gas and simultaneously emit an ion beam to interact with the deposited film. Using this plasma source and a mixture of argon and C2H2 gas, a-C:H films were deposited at a rate of ∼26 nm/min. The resulting a-C:H film of 1.2 µm thick was still highly transparent with a transmittance of over 90% in the infrared range and an optical bandgap of 2.04 eV. Young’s modulus of the a-C:H film was ∼80 GPa. The combination of the low-temperature high-rate deposition of transparent a-C:H films with moderately high Young’s modulus makes the single-beam plasma source attractive for many coatings applications, especially in which heat-sensitive and soft materials are involved. The single-beam plasma source can be configured into a linear structure, which could be used for large-area coatings.
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This content will become publicly available on January 1, 2026
Beam Plasma Source-Enhanced Deposition of Hydrophobic Fluorocarbon Thin Films
Fluorocarbon thin films are widely used in protective coatings due to their distinctive physical and chemical properties. However, their inherent lubricating nature often results in low scratch resistance and poor adhesion to substrates. In this study, a beam plasma source was employed to deposit fluorocarbon thin films, resulting in enhanced adhesion and scratch resistance while preserving optical transmittance and hydrophobicity. The beam plasma source can generate high-density plasma, resulting in the effective dissociation of the C4F8 source gas, as evidenced by the large ion current and high film deposition rates. A unique feature of this beam plasma source is that it can simultaneously emit a single broad beam of ions with independently controllable ion energy and flux to interact with the film. The fluorocarbon films exhibit high hydrophobicity with a contact angle of about 105°, a high optical transmittance of 85–90% in the visible wavelength range, and exceptional scratch resistance and durability.
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- Award ID(s):
- 2243110
- PAR ID:
- 10610943
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Coatings
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2079-6412
- Page Range / eLocation ID:
- 110
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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