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Optical Non-Invasive Evaluation of Ferroelectric Films/Memory Capacitors

Published online by Cambridge University Press:  16 February 2011

Sarita Thakoor ,
A. P. Thakoor  and
L. Eric Cross
Sarita Thakoor
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109
A. P. Thakoor
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109
L. Eric Cross
Affiliation:
Pennsylvania State University, Materials Research Laboratory, University Park, PA
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Abstract

NON-INVASIVE photoresponse (photocurrent/voltage, reflectance and transmittance) from ferroelectric thin films and memory capacitors, with its strong dependence not only on the remanent polarization, but also on the film microstructure, crystal orientation, and nature of the interfaces (state of formation/degradation, etc.) offers an excellent “tool” for probing the ferroelectric capacitors at virtually any stage of fabrication, including on-line quality control. In fact, simultaneous measurement of spectral photoresponse and spectral reflectance, as a distinctive signature of the device probed, is an ideal, high speed, non-invasive means of evaluation for such thin films at high spatial resolution (∼ 100 nm) using beam scanning. This paper discusses three aspects of such evaluation. First, the spectral transmittance of the film as a direct function of the microstructure, second, the use of band-gap illumination (365 nm) to condition a fatigued capacitor; and third, the optical E field interaction with the ferroelectric capacitor, yielding a high speed photoresponse which is related to the remanent polarization and the operational history (status of internal fields) of the ferroelectric capacitor. Combined, these different kinds of photoresponses provide a good signature of the device quality.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 360 , 1994 , 157
Copyright
Copyright © Materials Research Society 1995

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References

references

1.Kinney, W., Integrated Ferroelectrics, 4(2), 131, (1994).Google Scholar
2.Kinney, W. and Gealy, F. D., IEEE International Solid State Circuits Conference, p. 266, (1994).Google Scholar
3.Evans, J. T. and Womack, R., An Experimental 512 bit Non-volatile Memory with Ferroelectric Storage Cell, IEEE Journal of Solid-State Circuits, 23, 1171–1176 (1988).Google Scholar
4.Bondurant, D. and Gnandinger, F., Ferroelectric Non-volatile RAMs, IEEE Spectrum, 18, 30–33 (1989).Google Scholar
5.Scott, J. F. and Araujo, C. A. Paz De, Ferroelectric Memories, Science, 246, 1400–1405 (1989). Proceedings of the International Symposium on Integrated Ferroelectrics 1993 and 1994 - Integrated Ferroelectrics Volume 4 & 5. Ferroelectric Thin Films II (Vol. 243) and III (Vol. 310), Published by Materials Research Society.Google Scholar
6.Huffman, M., Aroujo, C. A. Paz De, McMillan, L. D., Scott, M. C. and Echer, C., Paper # 12-10.3, Proceedings MRS Symposium on Ferroelectric Thin Films IV, Vol 361, (Fall 1994).Google Scholar
7.Thakoor, S., Appl. Phy. Lett. 60, 3319, 1992.Google Scholar
8.Thakoor, S., Thakoor, A. P. and Bernacki, S. E., Proc. Third International Symposium on Integrated Ferroelectrics, Pg. 262, April 3-5, 1991, Colorado Springs, Colorado.Google Scholar
9.Thakoor, S., Appl. Phy. Lett. 63, 3233, 1993.Google Scholar
10.Thakoor, S., Ferroelectrics,134, 355, 1992.Google Scholar
11.Thakoor, S. and Maserjian, J., “Photoresponse Probe of the Space Charge Distribution in Ferroelectric PZT Thin Film Memory Capacitors” J. Vac. Sci. & Tech A, 12, 295, Mar/April (1994). C. E. Land, J. Am. Ceram. Soc., 72, 2059 (1989).Google Scholar
12.Thakoor, S., Journal of Appl. Physics, 75 (10), 5409, May 15 (1994). S.Thakoor, U.S. Patent # 5372859, December 13, 1994.Google Scholar
13.Thakoor, S., Olson, E. and Nixon, R. H., “Optically Addressable Ferroelectric Memory and its Applications” Integrated Ferroelectrics”, 4, 257 (1994).Google Scholar
14.Thakoor, S. and Thakoor, A. P., “Optically Addressed Ferroelectric Memory with Non-Destructive Read Out, Applied Optics (in press, 1995).Google Scholar
15.Thakoor, S., Morookian, J. M., Hemmati, H. and Thakoor, A. P., International Symposium of Applied Ferroelectrics held August 7-10, 1994 at Penn State Scanticon, State College, Pennsylvania (unpublished).Google Scholar
16.Thakoor, S., New Technology Report # NPO - 19393/8994. S. Thakoor, NASA TechBriefs, Vol. 17, p. 54 May (1993).Google Scholar
17.Thakoor, S., U. S. Patent # 5196101, March 23, 1993.Google Scholar
18.Yi, G., Wu, Z. and Sayer, M., J. Appl. Phys. 64, 2717 (1988).Google Scholar
19.Bernstein, S. E. et al. , Proc. MRS Fall Meeting: Symposium on Ferroelectric Thin Films II, Vol 243, p 343, Published by Materials Research Society, Pittsburgh, Pennsylvania, Boston, Dec 2-4 (1991).Google Scholar
20.Lakata, M. and Thakoor, S., “Automated Ferroelectric Capacitor Testing System”, NASA Tech Briefs, 18, 30 (1994)15.Google Scholar
21.Chivikula, V. K., Proceedings MRS Symposium on Ferroelectric Thin Films IV, Vol 361, (Fall 1994).Google Scholar
22.Warren, W. L., Dimos, D., Tuttle, B. A., Nasby, R. D., and Pike, G. E., Proceedings MRS Symposium on Ferroelectric Thin Films IV, Vol 361, (Fall 1994).Google Scholar
23.Lee, J., Esayan, S., Safari, A. and Ramesh, R., Appl. Phys. Lett. 64 3646 (1994).Google Scholar