The Transactions of the Korean Institute of Electrical Engineers C (대한전기학회논문지:전기물성ㆍ응용부문C)

The Korean Institute of Electrical Engineers (대한전기학회)
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Microstructural Characterization of MOCVD RuOx Thin Films and Effects of Annealing Gas Ambient

MOCVD RuOx 박막의 미세구조 특성평가와 열처리 가스환경 영향

  • 김경원 (충북대학교 전기전자 및 컴퓨터공학부) ;
  • 김남수 (충북대학교 전기전자 및 컴퓨터공학부) ;
  • 최일상 (하이닉스반도체) ;
  • 김호정 (하이닉스반도체) ;
  • 박주철 (하이닉스반도체)
  • Published : 2002.09.01
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Abstract

RuOx thin films were fabricated by the method of liquid delivery MOCVD using Ru(C$_{8}$ $H_{13}$ $O_2$)$_3$ as the precursor and their thermal effects and conductivity were investigated. Ru films deposited at 25$0^{\circ}C$ were annealed at $650^{\circ}C$ for 1min with Ar, $N_2$ or N $H_3$ ambient. The changes of the micro-structure, the surface morphology and the electrical resistivity of the Ru films after annealing were studied. Ar gas was more effective than $N_2$ and N $H_3$ gases as an ambient gas for the post annealing of the Ru films, because of smaller resistivity and denser grains. The X-ray diffraction and X-ray photoelectron spectroscopy results indicate that the Ru $O_2$ phase and the silicidation are not observed regardless of the ambient gases. The minimum resistivity of the Ru film is found to have the value of 26.35 $\mu$Ω-cm in Ar ambient. Voids were formed at Ru/TiN interface of the Ru layer after annea1ing in $N_2$ ambient. The $N_2$ gas generated due to the oxidation of the TiN layer accumulated at the Ru/TiN interface, forming bubbles; consequently, the stacked film may peel off the Ru/TiN interface.e.

Keywords

References

  1. S. Bhaskar, S. B. Majumder, P. S. Dobal, R. S. Katiyar and S. B. Krupanidhi, 'Structural and electrical characteristics of $Pb0.90La0.15TiO_3$ thin films on diffent bottom electrodes', J. Appl. Phys., Vol. 89, no. 10, pp. 5637-5643, May 2001 https://doi.org/10.1063/1.1365062
  2. T. Suzuki, Y. Nishi and M. Fujimoto, 'Effect of Nonstoichiometry on Microstructure of Epitaxially Grown $BaTiO_3$ Thin Films', Jpn. J. Appl. Phys., Vol. 39, no. 10, pp. 5970-5976, October 2000 https://doi.org/10.1143/JJAP.39.5970
  3. S. M. Zanetti, P. R. Bueno, E. Leite, E. Longo and J. A. Varela, 'Ferroelectric and microstructural characteristics of $SrBi2Ta_2O_9$ thin films crystallized by the rapid thermal annealing process', J. Appl. Phys., vol. 89, no. 6, pp. 3416-3419, March 2001 https://doi.org/10.1063/1.1345850
  4. D. P. Vijay, S. B. Desu and W. Pan, 'Reactive Ion Etching of Lead Zirconate Titanate(PZT) Thin Film Capacitors', J. Electrochem. Soc., vol. 140, no. 9, pp. 2635-2639, September 1993 https://doi.org/10.1149/1.2220876
  5. J. H. Ahn, W. Y. Choi, W. J. Lee, H. G. Kim, 'Annealing of $RuO_2$ and Ru Bottom Electrodes and Its Effects on the Electrical Properties of (Ba,Sr)$TiO_3$ Thin Films', Jpn. J. Appl. Phys., vol. 37, no. 1, pp. 284-289, January 1998 https://doi.org/10.1143/JJAP.37.284
  6. Y. Kaga, Y. Abe, M. Kawamura and K. Sasaki, 'Thermal Stability of $RuO_2$ Thin Films and Effects of Annealing Ambient on Their Reduction Process', Jpn. J. Appl. Phys., vol. 38, no. 6A, pp. 3689-3692, June 1999 https://doi.org/10.1143/JJAP.38.3689
  7. A. Tsuzumitani, Y. Okuno, J. Shibata, T. Shimizu, K. Yamamoto and Y. Mori, 'Extendibility of $Ta_2O_5$ Metal-Insulator-Metal Capacitor Using Ru Electrode', Jpn. J. Appl. Phys., vol. 39, no. 4B, pp. 2073-2077, April 2000 https://doi.org/10.1143/JJAP.39.2073
  8. S. E. Park, H. M. Kim, K. B. Kim and S. H. Min, 'Metallorganic Chemical Vapor Deposition of Ru and $RuO_$ Using Ruthenocene Precursor and Oxygen Gas', J. Electrochem. Soc., vol. 147, no. 1, pp. 203-209, 2000 https://doi.org/10.1149/1.1393175
  9. S. Y. Kang, K. H. Choi, S. K. Lee, C. S. Hwang and H. H. Kim, 'Thermodynamic Calculations and Metallorganic Chemical Vapor Deposition of Ruthenium Thin Films Using Bis(ethyl-${\pi}$-cyclopentadienyl)Ru for Memory Applications', J. Electrochem. Soc., vol. 147, no. 3, pp. 1161-1167, 2000 https://doi.org/10.1149/1.1393330
  10. Y. C. Choi and B. S. Lee, 'Properties of Ru and $RuO_2$ Thin Films Prepared by Metalorganic Chemical Vapor Deposition', Jpn. J. Appl. Phys., vol. 38, no. 8, pp. 4876-4880, August 1999 https://doi.org/10.1143/JJAP.38.4876
  11. K. W. Kim, N. S. Kim, Y. S. Kim, I. S. Choi, H. J. Kim and J. C. Park, 'Fabrication and Characterization of Ru Thin Films Prepared by Liquid Delivery Metal-Organic Chemical Vapor Deposition', Jpn. J. Appl. Phys., vol. 41, no. 2A, pp. 820-825, February 2002 https://doi.org/10.1143/JJAP.41.820
  12. A. Grill, W. Kane, J. Viggiano, M. Brady and R. Laibowitz, 'Base electrodes for high dielectric constant oxide materials in silicon technology', J. Mater. Res., vol. 7, no. 12, pp. 3260-3265, December 1992 https://doi.org/10.1557/JMR.1992.3260
  13. S. Yamamichi, P-Y.Leasaicherre, H. Yamaguchi, K. Takemura;S. Sone, H. Yabuta, K. Sato, T. Tamura, K. Nakajima, S. Ohnishi, K. Tokashiki, Y. Hayashi, Y. Kato, Y. Miyasaka, M. Yoshida and H. One, 'An ECR MOCVD (Ba,Sr)$TiO_3$ based stacked capacitor technology with $RuO_2$/Ru/TiN/$TiSi_x$ storage nodes for Gbit-scale DRAMs', IEDM 95, pp. 119-122, 1995 https://doi.org/10.1109/IEDM.1995.497196
  14. J. G. Lee, Y. T. Kim, S. K. Min and S. H. Choh, "Effects of excess oxygen on the properties of reactively sputtered $RuO_x$ thin films', J. Appl. Phys., vol. 77, no. 10, pp. 5473-5475, May 1995 https://doi.org/10.1063/1.359595
  15. T. Aoyama, M. Kiyotoshi, S. Yamazaki and K. Eguchi, 'Chemical Vapor Deposition of Ru and Its Application in (Ba,Sr)$TiO_3$ Capacitors for Future Dynamic Random Access Memories', Jpn. J. Appl. Phys., vol. 38, no. 4B, pp. 2194-2199, April 1999 https://doi.org/10.1143/JJAP.38.2194
  16. M. Hiratani, Y. Matsui, K. Imagawa and S. Kimura, 'Hydrogen Reduction Properties of $RuO_2$ Electrodes', Jpn. J. Appl. Phys., vol. 38, no. 11A, pp. L1275-L1277, November 1999 https://doi.org/10.1143/JJAP.38.L1275
  17. Y. Matsui, M. Hiratani and S. Kimura, 'Thermal Stability of a $RuO_2$ Electrode Prepared by DC Reactive Sputtering', Jpn. J. Appl. Phys., vol. 39, no. 1, pp. 256-263, January 2000 https://doi.org/10.1143/JJAP.39.256