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Congruent melting of gallium nitride at 6 GPa and its application to single-crystal growth

Nature Materials volume 2, pages 735–738 (2003)Cite this article

Abstract

The synthesis of large single crystals of GaN (gallium nitride) is a matter of great importance in optoelectronic devices for blue-light-emitting diodes and lasers. Although high-quality bulk single crystals of GaN suitable for substrates are desired, the standard method of cooling its stoichiometric melt has been unsuccessful for GaN because it decomposes into Ga and N2 at high temperatures before its melting point. Here we report that applying high pressure completely prevents the decomposition and allows the stoichiometric melting of GaN. At pressures above 6.0 GPa, congruent melting of GaN occurred at about 2,220 °C, and decreasing the temperature allowed the GaN melt to crystallize to the original structure, which was confirmed by in situ X-ray diffraction. Single crystals of GaN were formed by cooling the melt slowly under high pressures and were recovered at ambient conditions.

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Figure 1: A series of X-ray diffraction profiles of GaN with increasing temperature at 2.0 and 6.0 GPa.
Figure 2: Phase diagram of GaN under high pressure and temperature.
Figure 3
Figure 4: X-ray oscillation photograph of the recovered GaN single crystal.

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References

  1. Kelly, M.K. et al. Large free-standing GaN substrates by hydride vapor phase epitaxy and laser-induced liftoff. Jpn J. Appl. Phys. 38, L217–L219 (1999).

    Article  CAS  Google Scholar 

  2. Yamane, H., Shimada, M., Sekiguchi, T. & DiSalvo, F.J. Morphology and characterization of GaN single crystals grown in a Na flux. J. Cryst. Growth 186, 8–12 (1998).

    Article  CAS  Google Scholar 

  3. Hasegawa, M. & Yagi, T. Growth of nitride crystals in a supercritical nitrogen fluid under high pressures and high temperatures yield using diamond anvils cells and YAG laser heating. J. Cryst. Growth 217, 349–354 (2000).

    Article  CAS  Google Scholar 

  4. Porowski, S. High pressure growth of GaN – new prospects for blue lasers. J. Cryst. Growth 166, 583–589 (1996).

    Article  CAS  Google Scholar 

  5. Porowski, S. & Grzegory, I. Thermodynamical properties of III–V nitrides and crystals growth of GaN at high N2 pressure. J. Cryst. Growth 178, 174–188 (1997).

    Article  CAS  Google Scholar 

  6. Krukowski, S. Growth of GaN single crystals under high nitrogen pressures and their characterization. Cryst. Res. Technol. 34, 785–795 (1999).

    Article  CAS  Google Scholar 

  7. Utsumi, W. et al. SPring-8 beamlines for the high pressure science with multi-anvil apparatus. Rev. High Press. Sci. Technol. 7, 1484–1486 (1998).

    Article  CAS  Google Scholar 

  8. Utsumi, W. et al. High pressure science with multi-anvil apparatus at the SPring-8. J. Phys. Condens. Matter 14, 10497–10504 (2002).

    Article  CAS  Google Scholar 

  9. Karpinski, J., Jun, J. & Porowski, S. Equilibrium pressure of N2 over GaN and high pressure solution growth of GaN. J. Cryst. Growth 66, 1–10 (1984).

    Article  CAS  Google Scholar 

  10. Van Vechten, J.A. Quantum dielectric theory of electronegativity in covalent systems. III. Pressure–temperature phase diagrams, heats of mixing, and distribution coefficients. Phys. Rev. B 7, 1479–1507 (1973).

    Article  CAS  Google Scholar 

  11. Okada, T., Utsumi, W., Kaneko, H., Yamakata, M. & Shimomura, O. In situ x-ray observations of the decomposition of brucite and graphite-diamond conversion in aqueous fluid under high pressure and high temperature. Phys. Chem. Minerals 29, 439–445 (2002).

    Article  CAS  Google Scholar 

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Acknowledgements

We thank H. Takei and H. Asaoka for encouragement and useful discussion.

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Authors and Affiliations

  1. Synchrotron Radiation Research Center, Japan Atomic Energy Research Institute, Mikazuki-cho, Sayo-gun, Hyogo, 679-5148, Japan

    Wataru Utsumi, Hiroyuki Saitoh, Hiroshi Kaneko, Tetsu Watanuki, Katsutoshi Aoki & Osamu Shimomura

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  1. Wataru Utsumi
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  2. Hiroyuki Saitoh
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  3. Hiroshi Kaneko
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Correspondence to Wataru Utsumi.

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Utsumi, W., Saitoh, H., Kaneko, H. et al. Congruent melting of gallium nitride at 6 GPa and its application to single-crystal growth. Nature Mater 2, 735–738 (2003). https://doi.org/10.1038/nmat1003

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