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Optimizing MIM Device Electrical Properties. Impact of Bottom Electrodes and High K Materials

Published online by Cambridge University Press:  01 February 2011

Marceline Bonvalot
Affiliation:
[email protected], United States
Christophe Vallée
Affiliation:
[email protected], LTM-CNRS, CEA-LETI, grenoble, Texas, France
Emmanuel Gourvest
Affiliation:
[email protected], LTM-CNRS, CEA-LETI, grenoble, Texas, France
Corentin Jorel
Affiliation:
[email protected], LTM-CNRS, CEA-LETI, grenoble, Texas, France
Patrice Gonon
Affiliation:
[email protected], LTM-CNRS, CEA-LETI, grenoble, Texas, France
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Abstract

High quality MIM capacitors with improved capacitance density, low leakage currents and linear C(V) behaviour are the object of active research, with potential applications in CMOS, BICMOS and bipolar technologies as filters, analog to digital converters and related radio-frequency operating devices. Several high-k materials (Ta2O5, HfO2, Y2O3, Al2O3-HfTiO, HfON-SiO2) have been put on trial as possible candidates for SiO2 substitution which is required by the aggressive downscaling of electronic devices. Among those, HfO2- based materials seem to offer promising properties, combining a high chemical stability with Si and a high k value. However, HfO2 shows a strong ability to favour charge defects such as oxygen vacancies, which in turn affect the intrinsic properties of devices such as threshold voltage or leakage currents. These oxygen vacancies are actually thought to accumulate in the vicinity of the electrode, thus forming an oxidized interfacial layer and inducing a significant voltage linearity degradation of MIM capacitors.

In this work, it will be shown that this oxide layer thickness can be strongly minimized by using appropriate bottom electrode material. Indeed, high work function materials can efficiently prevent oxygen vacancies charge stocking on their surface. Several MIM devices have been prepared based on HfO2, Al2O3 and SrTiO3 as dielectric materials, and TiN, WSi2.7 and Pt as bottom electrode material. All these devices have been fully characterized in terms of materials properties and electrical behaviour. These results have been analysed and show that a reduced dielectric thickness is preferred to achieve high capacitance density, but is also responsible for voltage linearity degradation. High work function electrode material can help improve this degraded linear behaviour, thanks to the formation of a reduced interfacial oxygen trap layer thickness. Leakage currents seem to be deeply correlated with the morphological state of the dielectric material, an amorphous state being obviously more efficient to prevent current pathways through grain boundaries.

All these results will be presented in detail and discussed with regards to different models proposed in the literature to account for these data.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

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References

REFERENCES

1. Blonkowski, S., Regache, M. and Halimaoui, A., J. Appl. Phys. 90, 1501 (2001).Google Scholar
2. Durand, C., Vallée, C., Loup, V., Salicio, O., Dubourdieu, C., Blonkowski, S., Bonvalot, M and Joubert, O., J. Vac. Sci. Technol. A 22, 655 (2004).Google Scholar
3. Hu, H., Zhu, C., Lu, Y. F., Wu, Y. H., Liew, T., Li, M. F., Cho, B. J., Choi, W. K. and Yakovlev, N. J. Appl. Phys. 94, 551, (2003).10.1063/1.1579550Google Scholar
4. Lee, S. Y., Kim, H., McIntyre, P. C., Saraswat, K. C. and Byun, J. S., Appl. Phys. Lett. 82 2874 (2003).Google Scholar
5. Chiang, K. C., Huang, C. C., Pan, H. C., Hsiao, C. N., Lin, J. W., Hsieh, I. J., Cheng, C. H., Chou, C. P., Chin, A., Wang, H. L. and McAlister, S. P., J. Electrochem. Soc. 154, G54 (2007).Google Scholar
6. Mikhelashvili, V., Thangadurai, P., Kaplan, W. D. and Eisenstein, G., Appl. Phys. Lett. 92, 132903 (2008).Google Scholar
7. Gusev, E. P., Narayanan, V. and Frank, M. M., IBM J. Res. Dev. 50, 387 (2006).Google Scholar
8. El Kamel, F., Gonon, P. and Vallée, C., Appl Phys. Lett. 91 172909 (2007).Google Scholar
9. Gonon, P. and Vallée, C., Appl. Phys. Lett. 90, 142906 (2007).Google Scholar
10. Durand, C., Vallée, C., Dubourdieu, C., Kahn, M., Dérivaz, M. and Blonkowski, S., J. Vac. Soc. Technol. A24, 459, (2006).Google Scholar
11. Hu, H., Zhu, C., Lu, Y. F., Li, M. F., Cho, B. J. and Choi, W. K., IEEE Electron Dev. Lett. 23, 514 (2002).Google Scholar
12. The International Technology Roadmap for Semiconductors, Semiconductor Industry Association (2003).Google Scholar
13. Dornisch, D., Wilk, G., Li, G., Ring, K. M., Howard, D. J. and Racanelli, M., ECS Trans. 6, 755 (2007).Google Scholar
14. Kahn, M., Vallée, C., Defay, E., Dubourdieu, C., Bonvalot, M., Blonkowski, S., Plaussu, J. R., Garrec, P. and Baron, T., Microelec. Rel. 47, 773 (2007).Google Scholar
15. van Dover, R. B., Fleming, R. M., Schneemeyer, L. F., Alers, G. B. and Werder, J., in Advanced dielectrics for gate oxide, DRAM and RF capacitors in IEDM Tech. Dig. (1998), pp. 823826.Google Scholar
16. Bonvalot, M., Kahn, M., Vallée, C., Dubourdieu, C., Ducoté, J. and Joubert, O., Proceedings of the 53rd American Vacuum Society (AVS) Symposium, San Francisco (2006).Google Scholar
17. Esaka, F., Furuya, K., Shimada, H., Imamura, M., Matsubayashi, M., Sato, H., Nishijima, A., Kawana, A., Ichimura, H. and Kikuchi, T., J. Vac. Sci. Technol. A15, 2521 (1997).Google Scholar
18. Logothetidis, G., Meletis, E. I., Stergioudis, G. and Adjaotter, A. A., Thin Solid Films 338, 304 (1999).Google Scholar
19. CWenger, h., Lupina, G., Lukosius, M, Seifarth, O., Müssig, H. J., Pasko, S. and Lohe, Ch., J. Appl. Phys. 103, 104103 (2008).Google Scholar
20. Robertson, J., Sharia, O. and Demkov, A. A., Appl. Phys. Lett. 91, 132912 (2007).Google Scholar
21. Gonon, P. and El Kamel, F., J. Appl. Phys. 101, 073901 (2007).Google Scholar
22. Lau, W. S., Appl. Phys. Lett. 90, 222904 (2007).Google Scholar
23. Xiong, K., Robertson, J. and Clark, S. J., Appl. Phys. Lett. 89, 022907 (2006).Google Scholar
24. Tse, K. et Roberston, J., Phys. Rev. Lett. 99, 086805 (2007)Google Scholar
25. Yeo, Y. C., King, T. J. and Hu, C., J. Appl. Phys. 92, 7266 (2002).Google Scholar