Plasma and Fusion Research

Volume 16, 1206038 (2021)

Rapid Communications

Effects of Substrate Temperature on Film Hardness and Hydrogen Content in Diamond-like Carbon Films Prepared with a Repetitive Nanosecond Pulsed Glow Hydrogen/Methane Discharge Plasma

Katsuya IOKA, Yusuke KIKUCHI, Takuma MINE, Ryohei MASAI and Mitsuyasu YATSUZUKA

: Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2280, Japan

(Received 15 December 2020 / Accepted 23 January 2021 / Published 26 February 2021)

Abstract

A repetitive nanosecond pulsed glow hydrogen/methane discharge plasma generated at 1.2 kPa gas pressure led to diamond-like carbon films with high hardness and a high-speed deposition rate of 0.13 μm/min. Film hardness showed strong substrate temperature dependence, reaching up to 15 GPa. Raman spectroscopy revealed that hydrogen content in the films decreased with increasing substrate temperature. The mechanisms of the changes in film hardness and hydrogen content are considered to be the substrate temperature dependence of the hydrogen abstraction reaction and etching by irradiation with hydrogen radicals.

Keywords

diamond-like carbon, nanosecond pulsed glow discharge, Raman spectroscopy

DOI: 10.1585/pfr.16.1206038

Full Text

PDF format (792Kbytes) PDF Download

References

[1] C. Zou et al., Jpn. J. Appl. Phys. 55, 115501 (2016).
[2] N. Ohtake et al., Jpn. J. Appl. Phys. 43, L1406 (2004).
[3] Y. Kikuchi et al., Jpn. J. Appl. Phys. 56, 100306 (2017).
[4] Y. Oka et al., IEEE Trans. Plasma Sci. 34, 1183 (2006).
[5] A.C. Ferrari et al., Phys. Rev. B 61, 14095 (2000).
[6] C. Cashiraghi et al., Diam. Relat. Mater. 14, 1098 (2005).
[7] A. von Keudell et al., Diam. Relat. Mater. 11, 969 (2002).
[8] M. Shinohara and H. Fujiyama, J. Plasma Fusion Res. 83, 935 (2007) (in Japanese).
[9] X. Dong et al., Jpn. J. Appl. Phys. 55, 01AA11 (2016).
[10] T. Ishikawa and J. Choi, Diam. Relat. Mater. 89, 94 (2018).
[11] H. Li et al., Thin Solid Films 515, 2153 (2006).