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Layer-by-layer assembled charge-trap memory devices with adjustable electronic properties

Abstract

We describe a versatile approach for preparing flash memory devices composed of polyelectrolyte/gold nanoparticle multilayer films. Anionic gold nanoparticles were used as the charge storage elements, and poly(allylamine)/poly(styrenesulfonate) multilayers deposited onto hafnium oxide (HfO2)-coated silicon substrates formed the insulating layers. The top contact was formed by depositing HfO2 and platinum. In this study, we investigated the effect of increasing the number of polyelectrolyte and gold nanoparticle layers on memory performance, including the size of the memory window (the critical voltage difference between the ‘programmed’ and ‘erased’ states of the devices) and programming speed. We observed a maximum memory window of about 1.8 V, with a stored electron density of 4.2 × 1012 cm−2 in the gold nanoparticle layers, when the devices consist of three polyelectrolyte/gold nanoparticle layers. The reported approach offers new opportunities to prepare nanostructured polyelectrolyte/gold nanoparticle-based memory devices with tailored performance.

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Figure 1: Thickness and charge density measurements of (PE/AuNP)n multilayers for n = 1–4.
Figure 2: Structure of a typical memory device prepared with the LbL technique.
Figure 3: Capacitance versus voltage (CV) curves for (PE/AuNP)n multilayers for n = 1–4.
Figure 4: Real-space imaging of programmed and erased states.

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References

  1. Wann, H. C. & Hu, C. High-endurance ultra-thin tunnel oxide in MONOS device structure for dynamic memory application. IEEE Electron. Dev. Lett. 16, 491–493 (1995).

    Article  CAS  Google Scholar 

  2. White, M. H., Adams, D. A. & Bu, J. On the go with SONOS. IEEE Circuits Dev. 16, 22–31 (2000).

    Article  Google Scholar 

  3. De Blauwe, J. Nanocrystal nonvolatile memory devices. IEEE Trans. Nanotech. 1, 72–77 (2002).

    Article  Google Scholar 

  4. Park, Y. et al. Highly manufacturable 32 Gb multi-level NAND flash memory with 0.0098 μm2 cell size using TANOS (Si-Oxide-Al2O3-TaN) cell technology. IEEE International Electron Devices Meeting (IEDM), December 11–13, 2.1 (San Francisco, California, 2006). http://ieeexplore.ieee.org/xpls/abs_all.jsp?isnumber=4139311&arnumber=4154319&count=284&index=156.

    Google Scholar 

  5. Liu, Z., Lee, C., Narayanan, V., Pei, G. & Kan, E. C. Metal nanocrystal memories — Part I: Device design and fabrication. IEEE Trans. Electron. Dev. 49, 1606–1613 (2002).

    Article  CAS  Google Scholar 

  6. Hanafi, H. I., Tiwari, S. & Khan, I. Fast and long retention-time nano-crystal memory. IEEE Trans. Electron. Dev. 43, 1553–1558 (1996).

    Article  CAS  Google Scholar 

  7. Decher, G. Fuzzy nanoassemblies: toward layered polymeric multicomposites. Science 277, 1232–1237 (1997).

    Article  CAS  Google Scholar 

  8. Cho, J., Quinn, J. F. & Caruso, F. Fabrication of polyelectrolyte multilayer films comprising nanoblended layers. J. Am. Chem. Soc. 126, 2270–2271 (2004).

    Article  CAS  Google Scholar 

  9. Cho, J., Hong, J., Char, K. & Caruso, F. Nanoporous block copolymer micelle/micelle multilayer films with dual optical properties. J. Am. Chem. Soc. 128, 9935–9942 (2006).

    Article  CAS  Google Scholar 

  10. Cho, J. & Caruso, F. Investigation of the interactions between ligand-stabilized gold nanoparticles and polyelectrolyte multilayer films. Chem. Mater. 17, 4547–4553 (2005).

    Article  CAS  Google Scholar 

  11. Cho, J. & Caruso, F. Polymeric multilayer films comprising deconstructible hydrogen-bonded stacks confined between electrostatically assembled layers. Macromolecules 36, 2845–2851 (2003).

    Article  CAS  Google Scholar 

  12. Quinn, J. F., Johnston, A. P. R., Such, G., Zelikin, A. N. & Caruso, F. Next-generation, sequentially assembled ultrathin films: beyond electrostatics. Chem. Soc. Rev. 36, 707–718 (2007).

    Article  CAS  Google Scholar 

  13. Caruso, F., Caruso, R. A. & Möwald, H. Nanoengineering of inorganic and hybrid hollow spheres by colloidal templating. Science 282, 1111–1114 (1998).

    Article  CAS  Google Scholar 

  14. Ouyang, J., Chu, C.-W., Szmanda, C. R., Ma, L. & Yang, Y. Programmable polymer thin film and non-volatile memory device. Nature Mater. 3, 918–922 (2004).

    Article  CAS  Google Scholar 

  15. Tseng, R. J., Huang, J., Ouyang, J., Kaner, R. B. & Yang, Y. Polyaniline nanofiber/gold nanoparticle nonvolatile memory. Nano Lett. 5, 1077–1080 (2005).

    Article  CAS  Google Scholar 

  16. Yang, Y., Ouyang, J., Ma, L., Tseng, R. J.-H. & Chu, C.-W. Electrical switching and bistability in organic/polymeric thin films and memory devices. Adv. Funct. Mater. 16, 1001–1014 (2006).

    Article  CAS  Google Scholar 

  17. Tan, Z., Samanta, S. K., Yoo, W. J. & Lee, S. Self-assembly of Ni nanocrystals on HfO2 and N-assisted Ni confinement for nonvolatile memory application. Appl. Phys. Lett. 86, 013107 (2005).

    Article  Google Scholar 

  18. Yeh, P. H. et al. Low-power memory device with NiSi2 nanocrystals embedded in silicon dioxide layer. Appl. Phys. Lett. 87, 193504 (2005).

    Article  Google Scholar 

  19. Yang, F. M. et al. Memory characteristics of Co nanocrystal memory device with HfO2 as blocking oxide. Appl. Phys. Lett. 90, 132102 (2007).

    Article  Google Scholar 

  20. Jaramillo, T. F., Baeck, S.-H., Cuenya, B. R. & McFarland, E. W. Catalytic activity of supported Au nanoparticles deposited from block copolymer micelles. J. Am. Chem. Soc. 125, 7148–7149 (2003).

    Article  CAS  Google Scholar 

  21. Naitabdi, A., Ono, L. K. & Cuenya, B. R. Local investigation of the electronic properties of size-selected Au nanoparticles by scanning tunneling spectroscopy. Appl. Phys. Lett. 89, 043101 (2006).

    Article  Google Scholar 

  22. Ha, T. H., Koo, H.-J. & Chung, B. H. Shape-controlled synthesis of gold nanoprisms and nanorods influenced by specific adsorption of halide ions. J. Phys. Chem. 111, 1123–1130 (2007).

    Article  CAS  Google Scholar 

  23. Cho, J., Char, K., Hong, J.-D. & Lee, K.-B. Fabrication of highly ordered multilayer films using a spin self-assembly method. Adv. Mater. 13, 1076–1078 (2001).

    Article  CAS  Google Scholar 

  24. Cho, J. & Char, K. Effect of layer integrity of spin self-assembled multilayer films on surface wettability. Langmuir 20, 4011–4016 (2004).

    Article  CAS  Google Scholar 

  25. Cho, J. et al. Effect of layer integrity of spin self-assembled multilayer films on surface wettability. Langmuir 22, 1356–1364 (2004).

    Article  Google Scholar 

  26. Cho, J. et al. Quantitative analysis on the adsorbed amount and structural characteristics of spin-assembled multilayer films. Polymer 44, 5455–5459 (2003).

    Article  CAS  Google Scholar 

  27. Durstock, M. F. & Rubner, M. F. Dielectric properties of polyelectrolyte multilayers. Langmuir 17, 7865–7872 (2001).

    Article  CAS  Google Scholar 

  28. Cho, Y., Kazuta, S. & Matsuura, K. Scanning nonlinear dielectric microscopy with nanometer resolution. Appl. Phys. Lett. 75, 2833–2835 (1999).

    Article  CAS  Google Scholar 

  29. Cho, Y., Kirihara, A. & Saeki, T. Scanning nonlinear dielectric microscope. Rev. Sci. Instrum. 67, 2297–2303 (1996).

    Article  CAS  Google Scholar 

  30. Lee, J.-S. et al. Data retention characteristics of nitride-based charge trap memory devices with high-k dielectrics and high-work-function metal gates for multi-gigabit flash memory. Jpn J. Appl. Phys. 45, 3213–3216 (2006).

    Article  CAS  Google Scholar 

  31. Corbierre, M. K. et al. Polymer-stabilized gold nanoparticles and their incorporation into polymer matrices. J. Am. Chem. Soc. 123, 10411–10412 (2001).

    Article  CAS  Google Scholar 

  32. Yamagata, Y. & Shiratori, S. Evaluation of electrical characteristics of the layer-by-layer self-assembled films after the various annealing temperatures. Thin Solid Films 438, 238–242 (2003).

    Article  Google Scholar 

  33. Köhler, K., Möhwald, H. & Sukhorukov, G. B. Thermal behavior of polyelectrolyte multilayer microcapsules: 2. Insight into molecular mechanisms for the PDADMAC/PSS system. J. Phys. Chem. B 110, 24002–24010 (2006).

    Article  Google Scholar 

  34. Wang, X., Liu, J., Bai, W. & Kwong, D.-L. A novel MONOS-type nonvolatile memory using high-k dielectrics for improved data retention and programming speed. IEEE Trans. Electron. Dev. 51, 597–602 (2004).

    Article  CAS  Google Scholar 

  35. Tan, Y. N., Chim, W. K., Choi, W. K., Joo, M. S. & Cho, B. J. Hafnium aluminum oxide as charge storage and blocking-oxide layers in SONOS-type nonvolatile memory for high-speed operation. IEEE Trans. Electron. Dev. 53, 654–662 (2006).

    Article  CAS  Google Scholar 

  36. Lee, C. H., Park, K. C. & Kim, K. Charge-trapping memory cell of SiO2/SiN/high-k dielectric Al2O3 with TaN metal gate for suppressing backward-tunneling effect. Appl. Phys. Lett. 87, 073510 (2005).

    Article  Google Scholar 

  37. Grabar, K. C., Freeman, R. G., Hommer, M. B. & Natan, M. J. Preparation and characterization of Au colloid monolayers. Anal. Chem. 67, 735–743 (1995).

    Article  CAS  Google Scholar 

  38. Buttry, D. Advances in Electroanalytical Chemistry: Applications of the QCM to Electrochemistry, A series (Marcel Dekker, New York, 1991).

    Google Scholar 

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Acknowledgements

This work was supported by the ERC Program of the MOST/KOSEF (R11-2005-048-00000-0) and the Australian Research Council under the Federation and Discovery Project Schemes. We acknowledge assistance from S. Oh in obtaining the SEM images and Y. J. Choi for the SNDM images.

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Authors and Affiliations

Authors

Contributions

J.S.L. and J.C. conceived and designed the experiments, C.L., I.K., J.P. and Y.M.K. performed the experiments, J.S.L and J.C analysed the data, H.S. and J.L. contributed to materials/analysis tools, and F.C. assisted with data interpretation and provided fruitful discussions. J.S.L, J.C. and F.C. co-wrote the paper.

Corresponding authors

Correspondence to Jang-Sik Lee or Jinhan Cho.

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Supplementary figures S1–S12 (PDF 1888 kb)

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Lee, JS., Cho, J., Lee, C. et al. Layer-by-layer assembled charge-trap memory devices with adjustable electronic properties. Nature Nanotech 2, 790–795 (2007). https://doi.org/10.1038/nnano.2007.380

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