Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-03T02:31:48.008Z Has data issue: false hasContentIssue false

Applying NiTi Shape-Memory Thin Films to Thermomechanical Data Storage Technology

Published online by Cambridge University Press:  01 February 2011

Wendy C. Crone
Affiliation:
Department of Engineering Physics, University of Wisconsin-Madison, Madison, WI, USA
Gordon A. Shaw
Affiliation:
Manufacturing Metrology, National Institute of Standards and Technology, Gaithersburg, MD, USA
Get access

Abstract

As the data storage density in cutting edge microelectronic devices continues to increase, the superparamagnetic effect poses a problem for magnetic data storage media. One strategy for overcoming this obstacle is the use of thermomechanical data storage technology. In this approach, data is written by a nanoscale mechanical probe as an indentation on a surface, read by a transducer built into the probe, and then erased by the application of heat. An example of such a device is the IBM millipede, which uses a polymer thin film as the data storage medium. It is also possible, however, to use other kinds of media for thermomechanical data storage, and in the following work, we explore the possibility of using thin film Ni-Ti shape memory alloy (SMA). Previous work has shown that nanometer-scale indentations made in martensite phase Ni-Ti SMA thin films recover substantially upon heating. Issues such as repeated thermomechanical cycling of indentations, indent proximity, and film thickness impact the practicability of this technique. While there are still problems to be solved, the experimental evidence and theoretical predictions show SMA thin films are an appropriate medium for thermomechanical data storage.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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. Otsuka, K.; Wayman, C. M. Shape Memory Materials; Cambridge University Press: Cambridge, 1999.Google Scholar
2. Gall, K.; Juntunen, K.; Maier, H. J.; Sehitoglu, H.; Chumlyakov, Y. I., Instrumented micro-indentation of NiTi SMAs. Acta. Mater., 49 32053217, 2001.Google Scholar
3. Gall, K.; Dunn, M. L.; Liu, Y.; Labossiere, P.; Sehitoglu, H.; Chumlyakov, Y. I., Micro and macro deformation of single crystal NiTi. J. Eng. Mat. Tech, 124 238245, 2002.Google Scholar
4. Ni, W.; Cheng, Y.; Grummon, D., Recovery of Microindents in a Nickel-Titanium SMA… App. Phys. Lett, 80(18), pp. 33103312, 2002.Google Scholar
5. Shaw, G. A.; Stone, D. S.; Johnson, A. D.; Ellis, A. B.; Crone, W. C., Shape memory effect in nanoindentation of nickel-titanium thin films. Applied Physics Letters, 83(2), pp. 257259, 2003.Google Scholar
6. Crone, W. C.; Shaw, G. A.; Stone, D. S.; Johnson, A. D.; Ellis, A. B., Shape Recovery after Nanoindentation of NiTi Thin Films. Proceedings of the SEM Annual Conference on Experimental Mechanics, 12 71–6, 2003.Google Scholar
7. Vettiger, P., Cross, B., Despone, M., Drechsler, U., Durig, U., Botsmann, B., Haberle, W., Lantz, M. A., Rothuizen, H. E., Stutz, R. and Binnig, G. K., IEEE Trans. Nanotechnol., 1, 3955 2002.Google Scholar
8. Shaw, G.A., Crone, W.C., “Direct Measurement of the Nanoscale Mechanical Properties of NiTi Shape Memory Alloy,” Materials Research Society 2003 Fall Meeting Proceedings, Symposium Q7.11: 16 (2003).Google Scholar
9. Shaw, G.A., Trethewey, J.S., Johnson, A.D., Drugan, W.J., Crone, W.C., “Thermomechanical High-Density Data Storage in a Metallic Material via the Shape-Memory Effect,” in review.Google Scholar
10. Johnson, K. L. Contact Mechanics; Cambridge University Press: Cambridge, 1994, p. 175.Google Scholar
11. Fu, Y.; Huang, W.; Du, H.; Huang, X.; Tan, J.; Gao, X., Characterization of TiNi SMA thin films for MEMS applications. Surf. Coat. Technol., 145, 107112, 2001.Google Scholar