Improved Deposited Oxide Interfaces from N₂ Conditioning of Bare SiC Surfaces

Abstract:

The benefits of a new method used to incorporate nitrogen at the dielectric/semiconductor interface of 4H-SiC oxide-based devices are presented. High temperature exposure of the SiC surface to hydrogen and nitrogen, prior to oxide deposition, greatly reduces the amount of electrically active defects to a density at least as low as the one of thermally formed interfaces. These results demonstrate the potential of increasing minority carrier mobility with a low gate dielectric forming thermal budget, with deposited dielectrics, and with limited health hazards.

• Periodical: Materials Science Forum (Volumes 717-720)
• Pages: 729-732
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.717-720.729
• Online since: May 2012
• Authors: John Rozen, Masahiro Nagano, Hidekazu Tsuchida
• Keywords: Deposited Oxide, Interface Trap Density, Nitridation, Passivation, Surface Treatment

References

[1] J. Rozen, A. C. Ahyi, X. Zhu, J. R. Williams, L. C. Feldman, Scaling between channel mobility and interface state density in SiC MOSFETs, IEEE Trans. Electron. Dev. 58 (2011) 3808.

DOI: 10.1109/ted.2011.2164800

[2] H. Li, S. Dimitrijev, H. B. Harrison, D. Sweatman, Interfacial characteristics of N2O and NO nitrided SiO2 grown on SiC by rapid thermal processing, Appl. Phys. Lett. 70 (1997) 2028.

DOI: 10.1063/1.118773

[3] G. Y. Chung, C. C. TiN, J. R. Williams, K. McDonald, R. K. Chanana, R. A. Weller, S. T. Pantelides, L. C. Feldman, Improved inversion mobility for 4H-SiC MOSFETs following high temperature anneals in nitric oxide, IEEE Electron Dev. Lett. 22, (2001) 176-178.

DOI: 10.1109/55.915604

[4] M. Noborio, J. Suda, T. Kimoto, Enhanced channel mobility in 4H-SiC MISFETs by utilizing deposited SiN/SiO2 stack gate structures, Mater Sci. Forum 600-603 (2009) 679-682.

DOI: 10.4028/www.scientific.net/msf.600-603.679

[5] S. Hino, T. Hatayama, J. Kato, E. Tokumitsu, N. Miura, T. Oomori, High channel mobility 4H-SiC metal-oxide-semiconductor field-effect transistor with low temperature metal-organic chemical-vapor deposition grown Al2O3 gate insulator, Appl. Phys. Lett. 92 (2008) 183503.

DOI: 10.1063/1.2903103

[6] D. L. Lichtenwalner, V. Misra, S. Dhar, S.-H. Ryu, A. Agarwal, High-mobility enhancement-mode 4H-SiC lateral field-effect transistors utilizing atomic layer deposited Al2O3 gate dielectric, Appl. Phys. Lett. 95 (2009) 152113.

DOI: 10.1063/1.3251076

[7] S. Wang, S. Dhar, S. R. Wang, A. C. Ahyi, A. Franceschetti, J. R. Williams, L. C. Feldman, S. T. Pantelides, Bonding at the SiC-SiO2 interface and the effects of nitrogen and hydrogen, Phys. Rev. Lett. 98 (2007) 026101.

DOI: 10.1103/physrevlett.98.026101

[8] T. Hiyoshi and T. Kimoto, Elimination of the major deep levels in n- and p-type 4H-SiC by two-step thermal treatment, Appl. Phys. Expr. 2 (2009) 091101.

DOI: 10.1143/apex.2.091101

[9] T. L. Biggerstaff, C. L. Reynolds Jr, T. Zheleva, A. Lelis, D. Habersat, S. Haney, S.-H. Ryu, A. Agarwal, G. Duscher, Relationship between 4H-SiC/SiO2 transition layer thickness and mobility, Appl. Phys. Lett. 95 (2009) 032108.

DOI: 10.1063/1.3144272

[10] T. Shirasawa, K. Hayashi, H. Yoshida, S. Mizuno, S. Tanaka, T. Muro, Y. Tamenori, Y. Harada, T. Tokushima, Y. Horikawa, E. Kobayashi, T. Kinoshita, S. Shin, T. Takahashi, Y. Ando, K. Akagi, S. Tsuneyuki, H. Tochihara, Atomic-layer-resolved bandgap structure of an ultrathin oxynitride-silicon film epitaxially grown on 6H-SiC(0001), Phys. Rev. B 79 (2009) 241301(R).

DOI: 10.1103/physrevb.79.241301