Impact of Interface Defect Passivation on Conduction Band Offset at SiO2/4H-SiC Interface


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The change in energy band alignment of thermally grown SiO2/4H-SiC(0001) structures due to an interface defect passivation treatment was investigated by means of synchrotron radiation photoelectron spectroscopy (SR-PES) and electrical characterization. Although both negative fixed charge and interface state density in SiO2/SiC structures were effectively reduced by high-temparature hydrogen gas annealing (FGA), the conduction band offset (ΔEc) at the SiO2/SiC interface was found to be decreased by about 0.1 eV after FGA. In addition, a subsequent vacuum annealing to induce hydrogen desorption from the interface resulted in not only a slight degradation in interface property but also a partial recovery of ΔEc value. These results indicate that the hydrogen passivation of negatively charged defects near the thermally grown SiO2/SiC interface causes the reduction in conduction band offset. Therefore, the tradeoff between interface quality and conduction band offset for thermally grown SiO2/SiC MOS structure needs to be considered for developing SiC MOS devices.



Materials Science Forum (Volumes 717-720)

Edited by:

Robert P. Devaty, Michael Dudley, T. Paul Chow and Philip G. Neudeck




T. Hosoi et al., "Impact of Interface Defect Passivation on Conduction Band Offset at SiO2/4H-SiC Interface", Materials Science Forum, Vols. 717-720, pp. 721-724, 2012

Online since:

May 2012




[1] H. -F. 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-(2030).


[2] K. Fukuda, S. Suzuki, T. Tanaka, K. Arai, Reduction of interface-state density in 4H–SiC n-type metal-oxide-semiconductor structures using high-temperature hydrogen annealing, Appl. Phys. Lett. 76 (2000) 1585-1587.


[3] V. V. Afanas'ev, M. Bassler, G. Pensl, M. J. Schulz, E. Stein von Kamienski, Band offsets and electronic structure of SiC/SiO2 interfaces, J. Appl. Phys. 79 (1996) 3108-3114.


[4] A. K. Agarwal, S. Seshadri, L. B. Rowland, Temperature dependence of Fowler–Nordheim current in 6H- and 4H-SiC MOS capacitors, IEEE Electron Dev. Lett. 18 (1997) 592-594.


[5] T. Hatakeyama, T. Suzuki, J. Senzaki, K. Fukuda, H. Matsuhata, T. Shinohe, K. Arai, Impact of the wafer quality on the reliability of MOS structure on the C-face of 4H-SiC, Mat. Sci. Forum 600-603 (2009) 783-786.


[6] T. Suzuki, J. Senzaki, T. Hatakeyama, K. Fukuda, T. Shinohe, K. Arai, Reliability of 4H-SiC(000-1) MOS gate oxide using N2O nitridation, Mat. Sci. Forum 615-617 (2009) 557-560.


[7] J. H. Stathis, Dissociation kinetics of hydrogen-passivated (100) Si/SiO2 interface defects, J. Appl. Phys. 77 (1995) 6205-6207.


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