Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-23T05:04:53.211Z Has data issue: false hasContentIssue false

Contact Resistivity of Laser Annealed SiGe for MEMS Structural Layers Deposited at 210°C

Published online by Cambridge University Press:  20 January 2011

Joumana El-Rifai
Affiliation:
IMEC, Leuven, Belgium. YJ-STRC, The American University in Cairo, New Cairo, Egypt. Katholieke Universiteit Leuven, Leuven, Belgium.
Ann Witvrouw
Affiliation:
IMEC, Leuven, Belgium.
Ahmed Abdel Aziz
Affiliation:
YJ-STRC, The American University in Cairo, New Cairo, Egypt.
Robert Puers
Affiliation:
IMEC, Leuven, Belgium. Katholieke Universiteit Leuven, Leuven, Belgium.
Chris Van Hoof
Affiliation:
IMEC, Leuven, Belgium. Katholieke Universiteit Leuven, Leuven, Belgium.
Sherif Sedky
Affiliation:
YJ-STRC, The American University in Cairo, New Cairo, Egypt. Physics Department, The American University in Cairo, New Cairo, Egypt.
Get access

Abstract

Lowering the silicon germanium (SiGe) deposition temperature from the current 450°C to below 250°C will enable processing Micro Electro-Mechanical Systems (MEMS) on flexible polymer instead of on rigid silicon substrates or glass carriers. A major disadvantage of such a low temperature deposition is that the films are amorphous, with high hydrogen content and yield poor electrical and mechanical properties. To ensure films suitable for MEMS applications, a post-deposition laser annealing (LA) treatment is used. It is essential that the contact resistance between the SiGe MEMS structural layer and any lower electrode is minimized. In this work we investigate what beneficial effect a LA treatment can have on the contact resistivity of an initially amorphous SiGe MEMS structural layer with a bottom TiN electrode. We report a minimum contact resistivity of 2.14×10−3 Ωcm2.

Type
Research Article
Copyright
Copyright © Materials Research Society 2011

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

1. Witvrouw, A., “The road to flexible MEMS integration. In: Passive and Electromechanical Materials and Integration,” Mater. Res. Soc. Symp. Proc., vol. 1075, 2008 CrossRefGoogle Scholar
2. Patil, S. et al. , “Performance of thin film silicon MEMS on flexible plastic substrates,” Sensors and Actuators A, vol. 144, pp. 201206, 2008 CrossRefGoogle Scholar
3. Young, N. et al. , “Low Temperature Poly-Si on Flexible Polymer Substrates for Active Matrix Displays and Other Applications,” Mat. Res. Soc. Symp. Proc., vol. 769, 2003 CrossRefGoogle Scholar
4. Xiao, S. et al. , “A novel fabrication process of MEMS devices on polyimide flexible substrates,” Microelectronic Engineering, vol. 85 no. 2, pp. 452457, 2008 CrossRefGoogle Scholar
5. Ma, X. et al. , “Laser-Induced Crystallization of a Si1-xGex Microstructure,” J. Mater. Synth. Process., vol. 10, no. 1, January 2002 CrossRefGoogle Scholar
6. Sedky, S. et al. , “Optimal Conditions for Micromachining Si1-xGex at 210ºC”, JMEMS, vol. 16, 3, pp. 581588, June 2007 Google Scholar
7. El-Rifai, J. et al. , “Laser-induced Crystallization of SiGe MEMS Structural Layers Deposited at Temperatures below 250°C,” Mater. Res. Soc. Symp. Proc., vol. 1153, A19.03, 2009 CrossRefGoogle Scholar
8. Gromova, M. et al. , “Characterization and strain gradient optimization of PECVD poly-SiGe layers for MEMS applications,” Sensors and Actuators A, vol. 130131, pp. 403410, 2006 CrossRefGoogle Scholar
9. El-Rifai, J. et al. , “Selective Laser Annealing for Improved SiGe MEMS Structural Layers at 210ºC,” Proc. IEEE MEMS 2010, pp. 324327, 2010 Google Scholar
10. Claes, G. et al. , “Improvement of the poly-SiGe electrode contact technology for MEMS,” J. Micromech. Microeng., vol. 20, 2010 CrossRefGoogle Scholar
11. Lin, H. et al. , “An Evaluation of Test Structures for Measuring the Contact Resistance of 3-D Bonded Interconnects,” ICMTS, pp. 123127, March 2008 Google Scholar
12. Voutsas, A. T. et al. , “The Impact of Annealing Ambient on the Performance of Excimer-Laser-Annealed Polysilicon Thin-Film Transistors,” J. Electrochem. Soc., vol. 149, no. 9, pp. 35003505, 1999 CrossRefGoogle Scholar