Rapid Growth of Nanostructured Diamond Film on Silicon and Ti-6Al-4V Alloy Substrates

Gopi K Samudrala; Yogesh K Vohra; Michael J Walock; Robin Miles

doi:10.3390/ma7010365

Rapid Growth of Nanostructured Diamond Film on Silicon and Ti-6Al-4V Alloy Substrates

Materials (Basel). 2014 Jan 13;7(1):365-374. doi: 10.3390/ma7010365.

Authors

Gopi K Samudrala¹, Yogesh K Vohra², Michael J Walock³, Robin Miles⁴

Affiliations

¹ Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294, USA. gopi@uab.edu.
² Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294, USA. ykvohra@uab.edu.
³ Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294, USA. mwalock@uab.edu.
⁴ Laser Inertial Fusion Energy, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA. miles7@llnl.gov.

Abstract

Nanostructured diamond (NSD) films were grown on silicon and Ti-6Al-4V alloy substrates by microwave plasma chemical vapor deposition (MPCVD). NSD Growth rates of 5 µm/h on silicon, and 4 µm/h on Ti-6Al-4V were achieved. In a chemistry of H₂/CH₄/N₂, varying ratios of CH₄/H₂ and N₂/CH₄ were employed in this research and their effect on the resulting diamond films were studied by X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy. As a result of modifying the stock cooling stage of CVD system, we were able to utilize plasma with high power densities in our NSD growth experiments, enabling us to achieve high growth rates. Substrate temperature and N₂/CH₄ ratio have been found to be key factors in determining the diamond film quality. NSD films grown as part of this study were shown to contain 85% to 90% sp³ bonded carbon.

Keywords: MPCVD; film growth; nanostructured diamond; thin film structure and morphology.