Deposition of diamond onto aluminum by electron cyclotron resonance microwave plasma-assisted CVD

Abstract

Diamond crystallites and thin films have been deposited onto polycrystalline aluminum substrates utilizing an electron cyclotron resonance microwave plasma-assisted chemical vapor deposition (ECR-PACVD) method. For all depositions, the substrates were biased to +40 V dc with respect to ground and their temperature was maintained at 500 °C. Similar deposits were obtained from two different feedgas systems at a total pressure of 1.33 Pa (10 mTorr). The first system consisted of a carbon monoxide (CO) and hydrogen (H₂) mixture (CO:H₂ = 20:80), and the second was a methane (CH₄), oxygen (O₂), and hydrogen (H₂) mixture (CH₄:O₂:H₂ = 21:10:69). The deposits were subsequently characterized by scanning electron microscopy, micro-Raman spectroscopy, and x-ray diffraction. The results of these analyses indicate that polycrystalline diamond was deposited onto aluminum substrates, as both individual crystallites and continuous films.