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Ultrahigh-quality silicon carbide single crystals

Nature volume 430, pages 10091012 (26 August 2004) | Download Citation

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Abstract

Silicon carbide (SiC) has a range of useful physical, mechanical and electronic properties that make it a promising material for next-generation electronic devices1,2. Careful consideration of the thermal conditions3,4,5,6 in which SiC {0001} is grown has resulted in improvements in crystal diameter and quality: the quantity of macroscopic defects such as hollow core dislocations (micropipes)7,8,9, inclusions, small-angle boundaries and long-range lattice warp has been reduced10,11. But some macroscopic defects (about 1–10 cm-2) and a large density of elementary dislocations ( 104 cm-2), such as edge, basal plane and screw dislocations, remain within the crystal, and have so far prevented the realization of high-efficiency, reliable electronic devices in SiC (refs 12–16). Here we report a method, inspired by the dislocation structure of SiC grown perpendicular to the c-axis (a-face growth)17, to reduce the number of dislocations in SiC single crystals by two to three orders of magnitude, rendering them virtually dislocation-free. These substrates will promote the development of high-power SiC devices and reduce energy losses of the resulting electrical systems.

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References

  1. 1.

    & Comparison of 6H-SiC, 3C-SiC, and Si for power devices. IEEE Trans. Electron Devices 40, 645–655 (1993)

  2. 2.

    , , , & Progress towards SiC products. Appl. Surf. Sci. 184, 393–398 (2001)

  3. 3.

    et al. Seeded sublimation growth of 6H and 4H–SiC crystals. Mater. Sci. Eng. B 61–62, 54–57 (1999)

  4. 4.

    , , & Global modeling of the SiC sublimation growth process: prediction of thermoelastic stress and control of growth conditions. J. Cryst. Growth 226, 501–510 (2001)

  5. 5.

    et al. In-situ observation of silicon carbide sublimation growth by X-ray topography. J. Cryst. Growth 222, 579–585 (2001)

  6. 6.

    , , , & Growth and evaluation of high quality SiC crystal by sublimation method. Mater. Sci. Forum 389–393, 87–90 (2002)

  7. 7.

    Capillary equilibria of dislocated crystals. Acta Crystallogr. 4, 497–501 (1951)

  8. 8.

    et al. Dislocation content of micropipes in SiC. Phys. Rev. Lett. 80, 740–741 (1998)

  9. 9.

    et al. Synchrotron radiographic study and computer simulation of reactions between micropipes in silicon carbide. J. Appl. Phys. 94, 7076–7082 (2003)

  10. 10.

    et al. High quality SiC substrates for semiconductor devices: from research to industrial production. Mater. Sci. Forum 389–393, 23–28 (2001)

  11. 11.

    et al. Sublimation-grown semi-insulating SiC for high frequency devices. Mater. Sci. Forum 433–436, 39–44 (2003)

  12. 12.

    , & Breakdown degradation associated with elementary screw dislocations in 4H-SiC p + n junction rectifiers. Solid-State Electron. 42, 2157–2164 (1998)

  13. 13.

    et al. Long term operation of 4.5 kV PiN and 2.5 kV JBS diodes. Mater. Sci. Forum 353–356, 727–730 (2001)

  14. 14.

    , , , & Impact of SiC structural defects on the degradation phenomenon of bipolar SiC devices. Mater. Sci. Forum 433–436, 917–920 (2003)

  15. 15.

    , & Long-term reliability of n-type 4H-SiC thermal oxides (3). In Extended Abstracts of the 51st Spring Meeting of the JSAP Vol. 1, 433 (The Japan Society for Applied Physics, Tokyo, 2004) [in Japanese]

  16. 16.

    et al. Impact of surface crystal-defects on TDDB event of SiC thermal oxide. In Extended Abstracts of the 51st Spring Meeting of the JSAP Vol. 1, 434 (The Japan Society for Applied Physics, Tokyo, 2004) [in Japanese]

  17. 17.

    , , & Sublimation growth of 6H- and 4H-SiC single crystals in the [11̄00] and [112̄0] directions. J. Cryst. Growth 181, 229–240 (1997)

  18. 18.

    Growth of silicon crystals free from dislocations. J. Appl. Phys. 30, 459–474 (1959)

  19. 19.

    Historical overview of silicon crystal pulling development. Mater. Sci. Eng. B 73, 7–15 (2000)

  20. 20.

    & Investigation of growth processes of ingots of silicon carbide single crystals. J. Cryst. Growth 43, 209–212 (1978)

  21. 21.

    & Step-controlled epitaxial growth of SiC: High quality homoepitaxy. Mater. Sci. Eng. R20, 125–166 (1997)

  22. 22.

    et al. Propagation of current-induced stacking faults and forward voltage degradation in 4H-SiC PiN diodes. Mater. Sci. Forum 389–393, 427–430 (2002)

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Acknowledgements

We thank Y. Hirose for the SMBXT experiment, T. Saito for discussions, and N. Sugiyama, M. Matsui and H. Kuno for other experimental support. The SMBXT experiments were performed at the SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (JASRI).Authors' contributions D.N. conceived the idea and the growth experiment, and together with I.G., A.O. and H.K. carried it out; D.N., S.Y. and T.I. executed the quality analysis; and D.N., S.O. and K.T. co-wrote the paper.

Author information

Affiliations

  1. Toyota Central R&D Laboratories, Inc., Nagakute, Aichi, 480-1192, Japan

    • Daisuke Nakamura
    • , Itaru Gunjishima
    • , Satoshi Yamaguchi
    • , Tadashi Ito
    • , Atsuto Okamoto
    •  & Kazumasa Takatori
  2. Research Laboratories, DENSO Corporation, 500-1, Nissin, Aichi, 470-0111, Japan

    • Hiroyuki Kondo
    •  & Shoichi Onda

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Competing interests

Toyota CRDL and Denso Corp. have applied for patents related to the subject of this Letter. Commercialization of the patents may result in financial benefits to the authors.

Corresponding author

Correspondence to Kazumasa Takatori.

Supplementary information

PDF files

  1. 1.

    Supplementary Figure 1

    X-ray incident angle (ω) scan rocking curves of the 0004 diffraction peak spectrum obtained from 4H-SiC {0001} substrate sliced from a-face {11̄00} growth ingot using c-face growth seed crystal.

  2. 2.

    Supplementary Figure 2

    X-ray topography obtained from {0001} substrate sliced from the a-face {11̄00} growth crystal.

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DOI

https://doi.org/10.1038/nature02810

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