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Hardness measurements at shallow depths on ultra-thin amorphous carbon films deposited onto silicon and Al2O3-TiC substrates

Biomedical Sciences Research Institute Computer Science Research Institute Environmental Sciences Research Institute Nanotechnology & Advanced Materials Research Institute

Lemoine, P, Zhao, JF, Quinn, JP, McLaughlin, JAD and Maguire, PD (2000) Hardness measurements at shallow depths on ultra-thin amorphous carbon films deposited onto silicon and Al2O3-TiC substrates. THIN SOLID FILMS, 379 (1-2). pp. 166-172. [Journal article]

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URL: http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TW0-41XM5PF-W-K&_cdi=5548&_user=126978&_orig=search&_coverDate=12%2F08%2F2000&_sk=996209998&view=c&wchp=dGLzVzz-zSkzk&md5=254a17b88bd08b03e3360332b51646ce&ie=/sdarticle.pdf

DOI: S0040-6090(00)01543-1

Abstract

We carried out shallow depth indentations on ultra-thin hydrogenated amorphous carbon (a-C:H) films deposited by plasma enhanced chemical vapour deposition onto silicon and Al2O3-TiC ceramic substrates. These measurements are relevant to data storage and microelectronic applications, which require sub-50-nm, wear protective overcoats. Weused the continuous stiffness measurement technique to monitor the Young Modulus (E) and the hardness (H) as a function of depth for films with thickness varying from 10 to 50 nm. Raman spectroscopy and atomic force spectroscopy show that the films have similar roughness and microstructural bonding environment. For all films, the sub-30-nm region shows a continuous increase of E and H with depth, with no discernible tip calibration artifact. Above 30 nm depth, the effect of the film is predominant, essentially hardening noticeably the silicon and softening slightly the ceramic substrate, with E and H valuestypical of a-C:H materials. Above 50 nm, the E and H curves are dominated by the properties of the substrates. Initial nano-scratch experiments indicate that the films have better wear resistance than the Al2O3-TiC substrate. Therefore, the hardness and wear of the samples show no correlation at these shallow depths. (C) 2000 Elsevier Science B.V. All rights reserved.

Item Type:Journal article
Keywords:carbon; hardness; tribology; interfaces
Faculties and Schools:Faculty of Computing & Engineering
Faculty of Computing & Engineering > School of Engineering
Research Institutes and Groups:Engineering Research Institute
Engineering Research Institute > Nanotechnology & Integrated BioEngineering Centre (NIBEC)
ID Code:309
Deposited By:Mrs Ann Blair
Deposited On:11 Sep 2009 14:02
Last Modified:19 Mar 2014 12:58

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