Publication: Nitrogen doping for adhesion improvement of DLC film deposited on Si substrate by Filtered Cathodic Vacuum Arc (FCVA) technique
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Issued Date
2014
Resource Type
File Type
application/pdf
ISSN
1694332
Other identifier(s)
2-s2.0-84903314909
Rights Holder(s)
Scopus
Bibliographic Citation
Applied Surface Science. Vol 310, (2014), p.284-292
Suggested Citation
Bootkul D., Supsermpol B., Saenphinit N., Aramwit C., Intarasiri S. Nitrogen doping for adhesion improvement of DLC film deposited on Si substrate by Filtered Cathodic Vacuum Arc (FCVA) technique. Applied Surface Science. Vol 310, (2014), p.284-292. doi:10.1016/j.apsusc.2014.03.059 Retrieved from: https://hdl.handle.net/20.500.14740/6424
Abstract
Diamond-like carbon (DLC) films have been used in many applications due to their attractive combination of properties including chemical inertness, corrosion protection, biocompatibility, high hardness, and low wear rates. However, they still have some limitations such as high internal stresses and low toughness which lead to poor adhesion of films. Synthesis of nitrogen-doped DLC (N-DLC) offers the possibility of overcoming these limitations. In this study, DLC films, namely tetrahedral amorphous carbon (ta-C) and nitrogen doped tetrahedral amorphous carbon (ta-C:N) were deposited on single crystalline Si wafer substrates using the Filtered Cathodic Vacuum Arc (FCVA) technique. Film characterizations were carried out by Raman spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), triboindenter tester and nano-scratch tester. Measurement results showed that intentionally doping with nitrogen reduced the carbon sp 3 content and increased the surface roughness in comparison with that of pure ta-C films. The hardness measurement confirmed the Raman and AFM analyses that adding nitrogen in ta-C films decreased the hardness, especially with high nitrogen content. However, the nano-scratch test revealed the increasing of the critical load with nitrogen. This work, then, extended its scope to investigate the properties of double-layer ta-C films which were composed of ta-C:N interlayer of various thickness around 10-30 nm and ta-C top-layer with thickness of around 80 nm. Microstructure characterization demonstrated that a ta-C:N interlayer gradually decreased the sp 3 fraction in the films and increased film roughness whenever the ta-C:N interlayer thickness increased. In this structure, the tribological property in terms of adhesion to the Si substrate was significantly improved by about 20-90%, but the mechanical property in terms of hardness was gradually degraded by about 2-10%, compared to pure ta-C film, when the ta-C:N interlayer thickness increased from around 10-30 nm. This indicates that the nitrogen-doped DLC interlayer may sacrifice the mechanical strength of the films but gain benefits in terms of the adhesion property. © 2014 Elsevier B.V.
Subject(s)
Adhesion
Amorphous carbon
Amorphous silicon
Atomic force microscopy
Biocompatibility
Carbon films
Corrosion protection
Diamond like carbon films
Hardness
Nitrogen
Scanning electron microscopy
Semiconductor doping
Silicon wafers
Substrates
Surface roughness
Vacuum applications
Vacuum technology
Diamond like carbon
Filtered cathodic vacuum arc
Nano-scratch tester
Tetrahedral amorphous carbon
Tetrahedral amorphous carbon (ta-C)
Amorphous films
Amorphous carbon
Amorphous silicon
Atomic force microscopy
Biocompatibility
Carbon films
Corrosion protection
Diamond like carbon films
Hardness
Nitrogen
Scanning electron microscopy
Semiconductor doping
Silicon wafers
Substrates
Surface roughness
Vacuum applications
Vacuum technology
Diamond like carbon
Filtered cathodic vacuum arc
Nano-scratch tester
Tetrahedral amorphous carbon
Tetrahedral amorphous carbon (ta-C)
Amorphous films