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Controlled nanoscale doping of semiconductors via molecular monolayers

Nature Materials volume 7, pages 62–67 (2008)Cite this article

Abstract

One of the major challenges towards scaling electronic devices to the nanometre-size regime is attaining controlled doping of semiconductor materials with atomic accuracy, as at such small scales, the various existing technologies suffer from a number of setbacks. Here, we present a novel strategy for controlled, nanoscale doping of semiconductor materials by taking advantage of the crystalline nature of silicon and its rich, self-limiting surface reaction properties. Our method relies on the formation of a highly uniform and covalently bonded monolayer of dopant-containing molecules, which enables deterministic positioning of dopant atoms on the Si surfaces. In a subsequent annealing step, the dopant atoms are diffused into the Si lattice to attain the desired doping profile. We show the versatility of our approach through controlled p- and n-doping of a wide range of semiconductor materials, including ultrathin silicon-on-insulator substrates and nanowires, which are then configured into novel transistor structures.

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Figure 1: Schematic diagram of the monolayer doping process for Si substrates.
Figure 2: X-ray photoelectron spectra of the Si 2p core region for an as-made (after 1 day exposure to ambient air) monolayer of the boron-containing compound and unreacted silicon with a native oxide layer (inset).
Figure 3: Boron monolayer doping (p-doping) of Si(100).
Figure 4: Phosphorous monolayer doping (n-doping) of Si.
Figure 5: Monolayer doping of nanostructured Si devices.

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References

  1. Peercy, P. S. The drive to miniaturization. Nature 406, 1023–1026 (2000).

    Article  CAS  Google Scholar 

  2. Claeys, C. Technological challenges of advanced CMOS processing and their impact on design aspects. VLSI Design 2004, 275–282 (2004).

    Article  Google Scholar 

  3. Xiong, S. & Bokor, J. A simulation study of gate line edge roughness effects on doping profiles of short-channel MOSFET devices. IEEE Trans. Electron Devices 51, 228–232 (2004).

    Article  Google Scholar 

  4. Jones, E. C. & Ishida, E. Shallow junction doping technologies for ULSI. Mater. Sci. Eng. 24, 1–80 (1998).

    Article  Google Scholar 

  5. Lundstrom, M. Moore’s law forever? Science 299, 210–211 (2003).

    Article  CAS  Google Scholar 

  6. Wong, P. H.-S. Beyond the conventional transistor. Solid-State Electron. 49, 755–762 (2005).

    Article  CAS  Google Scholar 

  7. Chau, R. et al. Silicon nano-transistors and breaking the 10 nm physical gate length barrier. Device Research Conf. 2003, 123–126 (2003).

    Article  Google Scholar 

  8. Lu, W. & Lieber, C. M. Semiconductor nanowires. J. Phys. D 39, R387–R406 (2006).

    Article  CAS  Google Scholar 

  9. Wang, D., Sheriff, B. & Heath, J. R. Silicon p-FETs from ultrahigh density nanowire arrays. Nano Lett. 6, 1096–1100 (2006).

    Article  CAS  Google Scholar 

  10. Chen, P. et al. Atomic layer deposition to fine-tune the surface properties and diameters of fabricated nanopores. Nano Lett. 4, 1333–1337 (2004).

    Article  CAS  Google Scholar 

  11. Parviz, B. A., Ryan, D. & Whitesides, G. M. Using self-assembly for the fabrication of nano-scale electronic and photonic devices. IEEE Trans. Adv. Packag. 26, 233–241 (2003).

    Article  CAS  Google Scholar 

  12. Chang, L. & Wong, P. H.-S. Diblock copolymer directed self-assembly for CMOS device fabrication. Proc. SPIE 6156, 1–6 (2006).

    Google Scholar 

  13. Song, Y. H. et al. A novel atomic layer doping technology for ultra-shallow junction in sub-0.1 pm MOSFETs. IEEE IEDM 1999, 505–508 (1999).

    Google Scholar 

  14. Kalkofen, B., Lisker, M. & Burte, E. P. Phosphorus diffusion into silicon after vapor phase surface adsorption of phosphine. Mater. Sci. Eng. B 124–125, 288–292 (2005).

    Article  Google Scholar 

  15. Agrawal, A. IEEE Int. Conf. on Ion Implantation Technology Proceedings 2000 293–299 (Alpbach, Austria, 2000).

    Google Scholar 

  16. Privitera, V. Ultra-low energy ion implantation of boron for future silicon devices. Curr. Opin. Solid State Mater. Sci. 6, 55–65 (2002).

    Article  CAS  Google Scholar 

  17. Moon, C.-R. et al. Application of plasma-doping technique to reduce dark current of CMOS image sensors. IEEE Electron. Dev. Lett. 28, 114–116 (2007).

    Article  CAS  Google Scholar 

  18. Sieval, A. B., Vleeming, V., Zuilhof, H. & Sudholter, E. J. R. An improved method for the preparation of organic monolayers of 1-alkenes on hydrogen-terminated silicon surfaces. Langmuir 15, 8288–8291 (1999).

    Article  CAS  Google Scholar 

  19. Filler, M. A. & Bent, S. F. The surface as molecular reagent: Organic chemistry at the semiconductor interface. Prog. Surf. Sci. 73, 1–56 (2003).

    Article  CAS  Google Scholar 

  20. Linford, M. R. & Chidsey, C. E. D. Alkyl monolayers covalently bonded to silicon surfaces. J. Am. Chem. Soc. 115, 12631–12632 (1993).

    Article  CAS  Google Scholar 

  21. Webb, L. J. & Lewis, N. S. Comparison of the electrical properties and chemical stability of crystalline silicon(111) surfaces alkylated using grignard reagents or olefins with Lewis acid catalysts. J. Phys. Chem. B 107, 5404–5412 (2003).

    Article  CAS  Google Scholar 

  22. Bentzen, A., Schubert, G., Christensen, J. S., Svensson, B. G. & Holt, A. Influence of temperature during phosphorus emitter diffusion from a spray-on source in multicrystalline silicon solar cell processing. Prog. Photovolt. Res. Appl. 15, 281–289 (2007).

    Article  CAS  Google Scholar 

  23. Susa, M., Kawagishi, K., Tanaka, N. & Nagata, K. Diffusion mechanism of phosphorus from phosphorous vapor in amorphous silicon dioxide film prepared by thermal oxidation. J. Electrochem. Soc. 144, 2552–2558 (1997).

    Article  CAS  Google Scholar 

  24. Byon, K., Thanm, D., Fischer, J. E. & Johnson, A. T. Synthesis and postgrowth doping of silicon nanowires. Appl. Phys. Lett. 87, 193104 (2005).

    Article  Google Scholar 

  25. Lieber, C. M. & Wang, Z. L. Functional nanowires. Mater. Res. Soc. Bull. 32, 99–108 (2007).

    Article  CAS  Google Scholar 

  26. Huang, Y. et al. Logic gates and computation from assembled nanowire building blocks. Science 294, 1313–1317 (2001).

    Article  CAS  Google Scholar 

  27. Patolsky, F., Timko, B. P., Zheng, G. & Lieber, C. M. Nanowire-based nanoelectronic devices in the life sciences. Mater. Res. Soc. Bull. 32, 142–149 (2007).

    Article  CAS  Google Scholar 

  28. Beckman, R. A. et al. Fabrication of conducting Si nanowire arrays. J. Appl. Phys. 96, 5921–5923 (2004).

    Article  CAS  Google Scholar 

  29. Zhu, Z.-T., Menard, E., Hurley, K., Nuzzo, R. G. & Rogers, J. A. Spin on dopants for high-performance single-crystal silicon transistors on flexible plastic substrates. Appl. Phys. Lett. 86, 133507 (2005).

    Article  Google Scholar 

  30. Kinoshita, A., Tanaka, C., Uchida, K. & Koga, J. VLSI Technol. Kyoto, Japan 158–159 (IEEE, Piscataway, 2005).

    Google Scholar 

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Acknowledgements

We are indebted to C. Hu for insightful discussions and suggestions. We thank M. Rolandi for help with ellipsometry measurements. This work was supported by the MARCO MSD Focus Center Research Program, Lawrence Berkeley National Laboratory, a Junior Faculty Research Award from UC Berkeley and a Human Frontiers Science Program fellowship (R.Y.). All fabrication was carried out in the Berkeley Microlab facility.

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Author notes

  1. Johnny C. Ho and Roie Yerushalmi: These authors contributed equally to this work

Authors and Affiliations

  1. Department of Electrical Engineering and Computer Sciences, University of California at Berkeley, Berkeley, California 94720, USA

    Johnny C. Ho, Roie Yerushalmi, Zachery A. Jacobson, Zhiyong Fan, Robert L. Alley & Ali Javey

  2. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    Johnny C. Ho, Roie Yerushalmi, Zachery A. Jacobson, Zhiyong Fan & Ali Javey

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Contributions

J.C.H., R.Y., Z.A.J., Z.F. and R.L.A. carried out the experiments. All authors contributed to designing the experiments, analysing the data and writing the manuscript.

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Correspondence to Ali Javey.

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Ho, J., Yerushalmi, R., Jacobson, Z. et al. Controlled nanoscale doping of semiconductors via molecular monolayers. Nature Mater 7, 62–67 (2008). https://doi.org/10.1038/nmat2058

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