Reverse bias-dependence of schottky barrier height on silicon carbide: influence of the temperature and donor concentration


  • Abdelhakim Latreche Département des sciences de la matière, université de Bordj Bou Arreridj, Algeria





The work deals with the dependences of the Schottky barrier height (SBH) on the reverse bias voltage, temperature and on donor concentration of metal/4H-SiC Schottky diodes. Using the tunneling modeling we have shown that the Schottky barrier height on silicon carbide strongly depends on the reverse bias voltage, temperature and doping concentration. At room temperature, the Schottky barrier height increases with increasing the reverse bias voltage at high doping concentration (about 1016 cm-3), while, at low doping concentration (about 1015 cm-3) the Schottky barrier height decreases with increasing the reverse bias voltage. These behaviors are independent of the Schottky barrier lowering effect. That means other effects occur at the barrier and depend on the reverse applied bias. The barrier height increases with increasing temperature and doping concentration under reverse bias conditions. The barrier heights extracted from the Padovani-Stratton formulas are close to the barrier heights extracted from the Tsu-Esaki formula in particular for the thermionic-field emission.

Keywords: Extraction, Schottky Barrier Height, Reverse Bias, Tunneling, Silicon Carbide.


A. Mahajan, and B. J. Skromme, "Design and optimization of junction termination extension (JTE) for 4H–SiC high voltage Schottky diodes", Solid-State Electron., Vol. 49, (2005), pp. 945-955.

H. Matsunami, "Current SiC technology for power electronic devices beyond Si, Microelectronic Engineering, Vol. 83, (2006), pp. 2-4.

J. Crofton, and S. Sriram, "Reverse Leakage Current Calculations for SiC Schottky Contacts", IEEE Trans.Electron. Devices, Vol. 43, (1996), pp. 2305-2307.

M. Furno, F. Bonani, and G. Ghione, "Transfer matrix method modelling of inhomogeneous Schottky barrier diodes on silicon carbide", Solid-State Electron., Vol. 51, (2007), pp. 466-474.

K. J. Schoen, J. M. Woodall, J. A. Cooper Jr, and M. R. Melloch, "Design Considerations and Experimental Analysis of High-Voltage SiC Schottky Barrier Rectifiers", IEEE Trans.Electron. Devices, Vol. 45, (1998), pp. 1595-1604.

K. Vassilevski, I. Nikitina, P. Bhatnagar, A. Horsfall, N. Wright, A. G. O'Neill, M. Uren, K. Hilton, A. Munday, A. Hydes, and C. M. Johnson, "High temperature operation of silicon carbide Schottky diodes with recoverable avalanche breakdown", Mater. Sci. Forum, 527–529, (2006), pp. 931-934.

L. Zheng, R. P. Joshi, and C. Fazi, "Effects of barrier height fluctuations and electron tunneling on the reverse characteristics of 6H–SiC Schottky contacts", J. Appl. Phys., Vol. 85, (1999), pp. 3701-3707.

D. Blasciuc-Dimitriu, A. B. Horsfall, N. G. Wright, C. M. Johnson, K. V. Vassilevski, and A. G. O'Neill, "Quantum modelling of I–V characteristics for 4H–SiC Schottky barrier diodes", Semicond.Sci.Technol., Vol. 20, (2005), pp. 10-15.

S. Oyama, T. Hashizume, and H. Hasegawa, "Mechanism of Current Leakage through Metal/n-GaN interfaces", Appl.Surf. Scie., Vol. 190, (2002), pp. 322-325. (01)00902-3.

E. J. Miller, E. T. Yu, P. Waltereit, and J. S. Speck, "Analysis of reverse-bias leakage current mechanisms in GaN grown by molecular-beam epitaxy", Appl. Phys. Lett., Vol. 84, (2004), pp. 535-537.

E. H. Rhoderick, "Metal-semiconductor contacts", IEE PROC., Vol. 126, (1982), pp. 1-14.

R. Tsu, and L. Esaki, Tunneling in finite superlattice, Appl.phys.lett., Vol. 22, (1973), pp. 562-564.

F. A. Padovani, and R. Stratton, "Field and thermionic-field emission in Schottky barriers", Solid-State Electron., Vol. 9, (1966), pp. 695-707. (66)90097-9.

C. R. Crowell, "The Richardson constant for thermionic emission in Schottky barrier diodes", Solid-State Electron., Vol. 8, (1965), pp. 395-399. (65)90116-4.

J. Eriksson, N. Rorsman, and H. Zirath, "4H-Silicon Carbide Schottky Barrier Diodes for Microwave Applications", IEEE Trans.Microwave Theory Technol., Vol. 51, (2003), pp. 796-804.

A. Latreche, and Z. Ouennoughi, "Modified Airy function method modeling of tunnelling current for Schottky barrier diodes on silicon carbide", Semicond. Sci. Technol., Vol. 28, (2013), pp. 105003: 1-8

J. Osvald, and E. Dobročka, "Generalized approach to the parameter extraction from I-V characteristics of Schottky diodes", Semicond. Sci. Technol., Vol. 11, (1996), pp. 1198-1202.

A. Itoh, and H. Matsunami, "Analysis of Schottky Barrier Heights of Metal/SiC Contacts and Its Possible Application to High-Voltage Rectifying Devices", phys. stat. sol. (a), Vol. 162, (1997), pp. 389-408.

F. Roccaforte, F. La Via, V. Raineri, R. Pierobon, and E. Zanoni, "Richardson's constant in inhomogeneous silicon carbide Schottky contacts", J. Appl. Phys., Vol. 93, (2003), pp. 9137-9144.

W. Götz, A. Schöner, G. Pensl, W. Suttrop, W. J. Choyke, R. Stein, and S. Leibenzeder, "Nitrogen donors in 4H silicon carbide", J. Appl. Phys., Vol. 73, (1993), pp. 3332-3338.

V. Saxena, J. Nong (Jim) Su, and A. J. Steckl, "High-Voltage Ni- and Pt-SiC Schottky Diodes Utilizing Metal Field Plate Termination", IEEE Trans.Electron. Devices, Vol. 46, (1999), pp. 456-464.

S. Nigam, J. Kim, B. Luo, F. Ren, G. Y. Chung, S. J. Pearton, J. R. Williams, K. Shenai, and P. Neudeck, "Effect of contact geometry on 4H-SiC rectifiers with junction termination extension", Solid-State Electron., Vol. 47, (2003), pp. 57-60. (02)00273-3.

K. Ohtsuka, Y. Matsuno, Y. Hase, H. Sugimoto, K. Fujihira, Y. Tarui, M. Imaizumi, T. Takami, and T. Ozeki, "Influence of pinning trap in Ti/4H–SiC Schottky barrier diode", Mat. Sci. semicon. Proc., Vol. 6, (2003), pp. 359-362.

P. A. Ivanov, I. V. Grekhov, A. S. Potapov, T. P. Samsonova, N. D. Il'inskaya, O. I. Kon'kov, and O. Yu Serebrennikova, "Excess Leakage Currents in High-Voltage 4H-SiC Schottky Diodes", Semiconductors, Vol. 44, (2010), pp. 653-656.

P. A. Ivanov, I. V. Grekhov, O. I Kon'kov, A. S. Potapov, T. P. Samsonova, and T. V. Semenov, "I–V Characteristics of High–Voltage 4H–SiC Diodes with a 1.1–eV Schottky Barrier", Semiconductors, Vol. 45, (2011), pp. 1374-1377.

A. Gehring, and S. Selberherr, "Modeling of Tunneling Current and Gate Dielectric Reliability for Nonvolatile Memory Devices", IEEE Trans.Device Mater. Reliab., Vol. 4, (2004), pp. 306-319.

C. R. Crowell, and S. M. Sze, "Mechanical Reflection of Electrons at Metal- Semiconductor Barriers: Electron Transport in Semiconductor-Metal-Semiconductor Structures", J.Appl.phys., Vol. 37, (1966), pp. 2683-2689.

M. K. Hudait, and S. B. Krupanidhi, "Doping dependence of the barrier height and ideality factor of Au/n-GaAs Schottky diodes at low temperatures", Physica B, Vol. 307, (2001), pp. 125-137. (01)00631-7.

Zs J. Horváth, I. Gyúró, M. Németh-Sallay, and P. Tüttö, "Near-interface concentration reduction in n-type Au/Cr-GaAs Schottky contacts", Vacuum, Vol. 40, (1990), pp. 201-203. (90)90156-S.

S. K. Noh, and P. Bhattacharya, "Determination of intrinsic barrier height in the Au/n-GaN contact system", Appl. Phys. Lett., Vol. 78, (2001), pp. 3642-3644.

A. L. Syrkin, J. M. Bluet, G. Bastide, T. Bretagnon, A. A. Lebedev, M. G. Rastegaeva, N. S. Savkina, and V. E. Chelnokov, "Surface barrier height in metal-SiC structures of 6H, 4H and 3C polytype", Mat. Sci.Eng. B, Vol. 46, (1997), pp. 236-239. (96)01978-2.

M. E. Aydın, N. Yıldırım, and A. Türüt, "Temperature-dependent behavior of Ni/4H-nSiC Schottky contacts", J. Appl. Phys., Vol. 102, (2007) 04370, pp.1-7.

A. Latreche, Z. Ouennoughi, A. Sellai, R. Weiss, and H. Ryssel, "Electrical characteristics of Mo/4H-SiC Schottky diodes having ion-implanted guard rings: temperature and implant-dose dependence", Semicond. Sci. Technol., Vol. 26, (2011) 085003, pp.1-9.

S. Toumi, A. Ferhat-Hamida, L. Boussouar, A. Sellai, Z. Ouennoughi, and H. Ryssel, "Gaussian distribution of inhomogeneous barrier height in tungsten/4H-SiC (000-1) Schottky diodes", Microelectron. Eng., Vol. 86, (2009), pp. 303-309.

S. M. Sze, and K. Ng. Kwok, "Physics of Semiconductor Devices", 3rd edition, Wiley, New York, (2007).

View Full Article: