Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-30T22:59:13.026Z Has data issue: false hasContentIssue false
  • English
  • Français

Planarisation of Patterned Aluminium/Diamond Surfaces for SAWdevices

Published online by Cambridge University Press:  01 February 2011

Anthony S. Holland ,
Geoffrey K. Reeves  and
Patrick W. Leech
Anthony S. Holland
Affiliation:
School of Electrical & Computer Systems Engineering, RMIT, Melbourne, Vic. 3001 Australia
Geoffrey K. Reeves
Affiliation:
School of Electrical & Computer Systems Engineering, RMIT, Melbourne, Vic. 3001 Australia
Patrick W. Leech
Affiliation:
Division of Manufacturing and Infrastructure Technology, CSIRO, Clayton, Vic. 3169, Australia
Get access

Abstract

A novel method for forming interdigitated electrodes for GHz Surface acoustic wave (SAW) devices on diamond using a damascene-like polishing technique is described. Low aspect ratio Al electrodes are recessed into the diamond substrates to create a near planar surface. This allows the deposition of higher quality oriented ZnO. CVD diamond samples were ion-beam etched with groove widths in the range 1-5μm to a depth of 80-120nm. Al (120nm thick) was sputter deposited on to the etched diamond and was polished using either (i) a solution of 0.05μm silica on a neoprene polishing cloth or (ii) using a ∼0.12mm thick PVDF (polyvinylidene difluoride) filter pad with colloidal solutions of silica. Using AFM scans and optical microscopy it was observed that the combination of method (i) with the small sample size resulted in significant hollowing-out of the Al electrodes and complete removal of Al from over 90% of the pad-interconnect area. The alternative technique in (ii) demonstrated far less Al removal and better uniformity in the electrode patterns.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 767: Symposium F – Chemical-Mechanical Planarization , 2003 , F5.9
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Fujii, S. Seki, Y.. Yoshida, K. Nakahata, H. Higaki, K. Kitabayashi, H. and Shikata, S. “Diamond Wafer for SAW application”, IEEE Ultrasonics Symposium Proceedings, 183–186, (1997).Google Scholar
2. Chalker, P.R. Joyce, T.B. Johnston, C. Crossley, J.A.A., Huddlestone, J. Whitfield, M.D. and Jackman, R.B. “Fabrication of aluminium nitride/ diamond and gallium nitride/ diamond SAWdevices”, Diamond and Related Materials 8(1), 309–313, (1999).Google Scholar
3. Hickernell, F. S. IEEE Transactions on Sonics and Ultrasonics, SU-32(5), 621–629, (1985).Google Scholar
4. Holland, A.S. Reeves, G.K. and Leech, P.W. “Effects of Non-PlanarSurfaces on the Growth of RF Magnetron Sputtered ZnO,” Mater. Res. Soc. Proc. 672, April 2001, O8.21.1–6.Google Scholar
5. Campbell, C. K. “Surface Acoustic Wave Devices for Mobile and Wireless Communications”, Academic Press 1998, p.71.Google Scholar
6. Furuya, A. and Hayashi, Y., “Microstructure of Aluminium Damascene Interconnects inlaid by Chemical Vapor Deposition”, Proc. Advanced Metalisation Conf., Orlando, Florida, (Sept. 1999), pp.27–32.Google Scholar
7. Leech, P.W. Reeves, G.K. Holland, A.S. and Shanks, F. “Ion beam etching of CVD diamond filmin Ar, Ar/O2 and Ar/CF4 gas mixtures”, Diamond and Related Materials 11, 833–836, (2002).Google Scholar