Hostname: page-component-8448b6f56d-wq2xx Total loading time: 0 Render date: 2024-04-15T22:39:47.145Z Has data issue: false hasContentIssue false

Microstructural and Compositional Analysis of Strontium-Doped Lead Zirconate Titanate Thin Films on Gold-Coated Silicon Substrates

Published online by Cambridge University Press:  15 January 2009

S. Sriram*
Affiliation:
Microelectronics and Materials Technology Centre, School of Electrical and Computer Engineering, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia
M. Bhaskaran
Affiliation:
Microelectronics and Materials Technology Centre, School of Electrical and Computer Engineering, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia
D.R.G. Mitchell
Affiliation:
Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation (ANSTO), PMB 1, Menai, New South Wales 2234, Australia
K.T. Short
Affiliation:
Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation (ANSTO), PMB 1, Menai, New South Wales 2234, Australia
A.S. Holland
Affiliation:
Microelectronics and Materials Technology Centre, School of Electrical and Computer Engineering, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia
A. Mitchell
Affiliation:
Microelectronics and Materials Technology Centre, School of Electrical and Computer Engineering, RMIT University, GPO Box 2476V, Melbourne, Victoria 3001, Australia
*
Corresponding author. E-mail: sharath.sriram@gmail.com
Get access

Abstract

This article discusses the results of transmission electron microscopy (TEM)-based characterization of strontium-doped lead zirconate titanate (PSZT) thin films. The thin films were deposited by radio frequency magnetron sputtering at 300°C on gold-coated silicon substrates, which used a 15 nm titanium adhesion layer between the 150 nm thick gold film and (100) silicon. The TEM analysis was carried out using a combination of high-resolution imaging, energy filtered imaging, energy dispersive X-ray (EDX) analysis, and hollow cone illumination. At the interface between the PSZT films and gold, an amorphous silicon-rich layer (about 4 nm thick) was observed, with the film composition remaining uniform otherwise. The films were found to be polycrystalline with a columnar structure perpendicular to the substrate. Interdiffusion between the bottom metal layers and silicon was observed and was confirmed using secondary ion mass spectrometry. This occurs due to the temperature of deposition (300°C) being close to the eutectic point of gold and silicon (363°C). The diffused regions in silicon were composed primarily of gold (analyzed by EDX) and were bounded by (111) silicon planes, highlighted by the triangular diffused regions observed in the two-dimensional TEM image.

Type
Materials Applications
Copyright
Copyright © Microscopy Society of America 2009

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

REFERENCES

Bedoya, C., Muller, Ch., Baudour, J.-L., Madigou, V., Anne, M. & Roubin, M. (2000). Sr-doped PbZr1−xTixO3 ceramic: Structural study and field-induced reorientation of ferroelectric domains. Mater Sci Eng B 75, 4352.CrossRefGoogle Scholar
Bhaskaran, M., Sriram, S. & Holland, A.S. (2006). RF magnetron sputtered perovskite-oriented PSZT thin films on gold for piezoelectric and ferroelectric transducers. Electron Lett 42, 244245.CrossRefGoogle Scholar
Kanamori, S. & Sudo, H. (1982). Effects of titanium layer as diffusion barrier in Ti/Pt/Au beam lead metallization on polysilicon. IEEE Trans Comp Hybrids Manuf Tech CHMT-5, 318321.CrossRefGoogle Scholar
Mitchell, D.R.G., Attard, D.J. & Triani, G. (2003). Transmission electron microscopy studies of atomic layer deposition TiO2 films grown on silicon. Thin Solid Films 441, 885895.CrossRefGoogle Scholar
Sriram, S., Bhaskaran, M. & Holland, A.S. (2006a). The effect of post-deposition cooling rate on the orientation of piezoelectric (Pb0.92Sr0.08)(Zr0.65Ti0.35)O3 thin films deposited by RF magnetron sputtering. Semiconductor Sci Tech 21, 12361243.CrossRefGoogle Scholar
Sriram, S., Bhaskaran, M. & Holland, A.S. (2006b). Surface morphology and stress analysis of piezoelectric strontium-doped lead zirconate titanate thin films. In Micro- and Nanotechnology: Materials, Processes, Packaging, and Systems III, Chiao, J.-C., Dzurak, A.S., Jagadish, C. & Thiel, D.V. (Eds.), p. 64150J. Proceedings of the SPIE, Vol. 6415.Google Scholar
Sriram, S., Bhaskaran, M., Holland, A.S., Short, K.T. & Latella, B.A. (2007). Measurement of high piezoelectric response of strontium-doped lead zirconate titanate thin films using a nanoindenter. J Appl Phys 101, 104910.CrossRefGoogle Scholar
Sumida, N. & Ikeda, K. (1991). Cross-sectional observations of gold-silicon reaction on silicon substrate in situ in the high-voltage electron microscope. Ultramicroscopy 39, 313320.CrossRefGoogle Scholar
Wasa, K., Kitabatake, M. & Adachi, H. (2004). Thin Film Materials Technology: Sputtering of Compound Materials. Heidelberg, Germany: Springer-Verlag GmbH & Co. KG.Google Scholar
Wenzel, R., Goesmann, F. & Schmid-Fetzer, R. (1998). Diffusion barriers in gold-metallized titanium-based contact structures on SiC. J Mater Sci: Mater Electron 9, 109113.Google Scholar
Zheng, H., Reaney, I.M., Lee, W.E., Jones, N. & Thomas, H. (2002). Surface decomposition of strontium-doped soft PbZrO3–PbTiO3. J Am Ceram Soc 85, 207212.CrossRefGoogle Scholar