Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Electrical Characteristics of Al2O3/TaAlO4/SiO2 Multi-layer Films by Different Tunnel Oxide Thicknesses and Annealing Treatment

터널링 산화막 두께 변화 및 열처리에 따른 Al2O3/TaAlO4/SiO2 다층막의 전기적 특성에 관한 연구

  • Park, Jung-Tae (Department of Materials science and Engineering, Yonsei University) ;
  • Kim, Hyo-June (Department of Materials science and Engineering, Yonsei University) ;
  • Choi, Doo-Jin (Department of Materials science and Engineering, Yonsei University)
  • 박정태 (연세대학교 신소재공학과) ;
  • 김효준 (연세대학교 신소재공학과) ;
  • 최두진 (연세대학교 신소재공학과)
  • Received : 2010.07.23
  • Accepted : 2010.08.17
  • Published : 2010.09.30
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Abstract

In this study, $Al_2O_3/TaAlO_4/SiO_2$ (A/TAlO/S) structures with tantalum aluminate charge trap layer were fabricated for Nand flash memory device. We evaluated the memory window and retention characteristic as the thickness of the tunnel oxide was varied among 3 nm, 4 nm, and 5 nm. All tunnel oxide thicknesses were measured by ellipsometer and TEM (Transmission Electron Microscope). The A/TAlO/S multi-layer film consisted of 5 nm tunnel oxide showed the best result of memory window of 1.57 V and retention characteristics. After annealing the 5 nm tunnel oxide A/TAlO/S multi-layer film at $900^{\circ}C$. The memory window decreased to 1.32 V. Moreover, the TEM images confirmed that the thickness of multi-layer structure decreased 14.3% after annealing and the program conditions of A/TAlO/S multi-layer film decreased from 13 V to 11 V for 100 ms. Retention properties of both as-deposited and annealed films stably maintained until to $10^4$ cycles.

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References

  1. K. Kim and S.Y. Lee, "Memory Technology in the Future," Microelectron. Eng., 84 [9-10] 1976-81 (2007). https://doi.org/10.1016/j.mee.2007.04.120
  2. M. H. White, D. A. Adams and J. Bu, "On the Go with SONOS," IEEE Circ. Dev. Mag., 16 [4] 22-31 (2000). https://doi.org/10.1109/101.857747
  3. C. T. Swift, G. L. Chindalore, K. Harber, Harp T. S., A. Hoefler, C. M. Hong, and Ingersoll P. A., "An Embedded 90 nm SONOS Nonvolatile Memory Utilizing Hot Electron Programming and Uniform Tunnel Erase," IEDM Tech. Dig., 8-11 927-30 (2002).
  4. Y. N. Tan, W. K. Chim, B. J. Cho, and W. K. Choi, "Over-Erase Phenomenon in SONOS-type Flash Memory and Its Minimization Using a Hafnium Oxide Charge Storage Layer," IEEE T. Electron. Dev., 51 [7] 1143-47 (2004). https://doi.org/10.1109/TED.2004.829861
  5. X. Wang and D. L. Kwong, "A Novel High-k SONOS Memory Using TaN/$Al_2O_3/Ta_2O_5/HfO_2$/Si Structure for Fast Speed and Long Retention Operation," IEEE T. Electron Dev., 53 [1] 78-82 (2003). https://doi.org/10.1109/TED.2005.860637
  6. B. Sen, H. Wong, J. Molina, H. Iwai, J. A. Ng, K. Kakushima, and C. K. Sarkar, "Trapping Characteristics of Lanthanum Oxide Gate Dielectric Film Explored from Temperature Dependent Current-voltage and Capacitancevoltage Measurements," Solid-State Electronics., 51 [3] 475-80 (2007). https://doi.org/10.1016/j.sse.2007.01.032
  7. S. H. Jeon, J. H. Han, and J. H. Lee, "High Work-function Metal Gate and High-k Dielectrics for Charge Trap Flash Memory Device Applications," IEEE T. Electron. Dev., 52 [12] 2654-59 (2005). https://doi.org/10.1109/TED.2005.859691
  8. H. J Kim, S. Y. Cha, and D. J. Choi, "A Study on the Electrical Properties of $Al_2O_3$/La2O3/$Al_2O_3$ Multi-Stacked Films Using Tunnel Oxide Annealed at Various Temperatures," J. Ceram. Soc. Jpn, 117 [5] 555-57 (2009). https://doi.org/10.2109/jcersj2.117.555
  9. Front-end processing, in International Technology Roadmap for Semiconductor (ITRS) (2008).
  10. R. Bez, E. Camerlenghi, A. Modelli, and A. Visconti, "Introduction to Flash memory," Proc IEEE, 91 [4] 489-502 (2003). https://doi.org/10.1109/JPROC.2003.811702
  11. H. C. Ham, J. H. Heo, C. W. Kim, and I. Chung, "Characterization of Program and Erase Properties Using Fowler–nordheim Tunneling in the 30 nm Silicon–oxide–nitride–oxide–silicon Transistor," Mater. Sci. Eng. B-Solid, 124-25[SUPPL.] 513-16 (2005). https://doi.org/10.1016/j.mseb.2005.08.118
  12. J. C. Zhou, D. T. Luo, Y. Z. Li, and Z. Liu, "Effect of Sputtering Pressure and Rapid Thermal Annealing on Optical Properties of $Ta_2O_5$ Thin Films," Trans. Nonferrous Met. Soc. China, 19 [2] 19359-363 (2009).
  13. J. H. Jun, C. H. Wang, D. J. Won, and D.J. Choi, "Structural and Electrical Properties od a $La_2O_3$ Thin Film as a Gate Dielectric," J. Kor. Phys. Soc., 41 [6] 998-1002 (2002).
  14. Front-end processing, in International Technology Roadmap for Semiconductor (ITRS) (2007).