Annealing of Ion Implantation Damage in SiC Using a Graphite Mask


For p-type ion implanted SiC, temperatures in excess of 1600 °C are required to activate the dopant atoms and to reduce the crystal damage inherent in the implantation process. At these high temperatures, however, macrosteps (periodic welts) develop on the SiC surface. In this work, we investigate the use of a graphite mask as an anneal cap to eliminate the formation of macrosteps. N-type 4H- and 6H-SiC epilayers, both ion implanted with low energy (keV) Boron (B) schedules at 600 °C, and 6H-SiC substrates, ion implanted with Aluminum (Al), were annealed using a Graphite mask as a cap. The anneals were done at 1660 °C for 20 and 40 minutes. Atomic force microscopy (AFM), capacitance-voltage (C-V) and secondary ion mass spectrometry (SIMS) measurements were then taken to investigate the effects of the anneal on the surface morphology and the substitutional activation of the samples. It is shown that, by using the Graphite cap for the 1660 °C anneals, neither polytype developed macrosteps for any of the dopant elements or anneal times. The substitutional activation of Boron in 6H-SiC was about 15%.

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  1. [1]

    M. Bhatnagar and B. J. Baliga, IEEE Trans. Electron Devices 40 (1993), p. 64 5.

    Article  Google Scholar 

  2. [2]

    M. V. Rao, J. A. Gardner, P. H. Chi, O. W. Holland, G. Kelner, J. Kretchmer, and M. Ghezzo, J. Appl. Phys. Vol. 81, No.10, p. 6635 (1997).

    CAS  Article  Google Scholar 

  3. [3]

    M. A. Capano, S. Ryu, M. R. Melloch, J. A. Cooper Jr, and M. R. Buss, J. Electronic Materials, Vol. 27, No. 4, (1998).

    Google Scholar 

  4. [4]

    CREE Research, Inc., Oral presentation at MURI review, (1999).

  5. [5]

    M. A. Capano et. al., Oral presentation at MURI review, (1999).

    Google Scholar 

  6. [6]

    L. Ottaviani, D. Planson, M. L. Locatelli, J. P. Chante, B. Canut, and S. Ramos, Material Science Forum, Vols. 264-268, p. 709 (1998).

    CAS  Article  Google Scholar 

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Correspondence to Chris Thomas.

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Thomas, C., Taylor, C., Griffin, J. et al. Annealing of Ion Implantation Damage in SiC Using a Graphite Mask. MRS Online Proceedings Library 572, 45 (1999).

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