Mechanics of hydrogenated amorphous carbon deposits from electron-beam-induced deposition of a paraffin precursor J. Appl. Phys. 98, 014905 (2005); 10.1063/1.1940138 Effects of thermal annealing on the structural, mechanical, and tribological properties of hard fluorinated carbon films deposited by plasma enhanced chemical vapor deposition In this work, antiwear nanoimprint templates were made by depositing and patterning diamondlike carbon ͑DLC͒ films on Si and quartz. A capacitively coupled plasma enhanced chemical vapor deposition ͑PECVD͒ system was configured to deposit 100 nm-1 m thick DLC films on Si and quartz substrates. These films were characterized with Raman spectroscopy, electron energy loss spectroscopy, atomic force microscopy, nanoindentation, contact angle measurements, and optical transmission measurements. The rf power and pressure of the PECVD process were varied to obtain uniform coating of DLC films with smooth surface ͑ϳ0.2 nm rms͒, low surface energy ͑ϳ40 mJ/ m 2 ͒, and high hardness ͑ϳ22 GPa͒. The resulting films' wear resistance is more than three times better than quartz. The DLC films were patterned by nanoimprint lithography using polymethylmethacrylate ͑PMMA͒ followed by CF 4 plasma etch. Thermal nanoimprint tests with DLC templates were performed in PMMA. Atomic force microscopy measurements indicated excellent pattern-transfer fidelity and template-polymer separation.
The interaction between resist and template during the separation process after nanoimprint lithography (NIL) can cause the formation of defects and damage to the templates and resist patterns. To alleviate these problems, fluorinated self-assembled monolayers (F-SAMs, i.e. tridecafluoro-1,1,2,2,tetrahydrooctyl trichlorosilane or FDTS) have been employed as template release coatings. However, we find that the FDTS coating undergoes irreversible degradation after only 10 cycles of UV nanoimprint processes with SU-8 resist. The degradation includes a 28% reduction in surface F atoms and significant increases in the surface roughness. In this paper, diamond-like carbon (DLC) films were investigated as an alternative material not only for coating but also for direct fabrication of nanoimprint templates. DLC films deposited on quartz templates in a plasma enhanced chemical vapor deposition system are shown to have better chemical and physical stability than FDTS. After the same 10 cycles of UV nanoimprints, the surface composition as well as the roughness of DLC films were found to be unchanged. The adhesion energy between the DLC surface and SU-8 is found to be smaller than that of FDTS despite the slightly higher total surface energy of DLC. DLC templates with 40 nm features were fabricated using e-beam lithography followed by Cr lift-off and reactive ion etching. UV nanoimprinting using the directly patterned DLC templates in SU-8 resist demonstrates good pattern transfer fidelity and easy template-resist separation. These results indicate that DLC is a promising material for fabricating durable templates for UV nanoimprint lithography.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.