Schottky Barrier Parameters of Pd/Ti Contacts on N-Type InP Revealed from I-V-T And C-V-T Measurements
D. Subba Reddy, M. Bhaskar Reddy, N. Nanda Kumar Reddy, V. Rajagopal Reddy
.
DOI: 10.4236/jmp.2011.23018   PDF    HTML     10,739 Downloads   21,752 Views   Citations

Abstract

We report on the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of the Pd/Ti/n-InP Schottky barrier diodes (SBDs) in the temperature range 160-400 K in steps of 40 K. The barrier heights and ideality factors of Schottky contact are found in the range 0.35 eV (I-V), 0.73 eV (C-V) at 160 K and 0.63 eV (I-V), 0.61 eV (C-V) at 400 K, respectively. It is observed that the zero-bias barrier height decreases and ideality factor n increase with a decrease in temperature, this behaviour is attributed to barrier inhomogeneities by assuming Gaussian distribution at the interface. The calculated value of series resistance (Rs) from the forward I-V characteristics is decreased with an increase in temperature. The homogeneous barrier height value of approximately 0.71 eV for the Pd/Ti Schottky diode has been obtained from the linear relationship between the temperature-dependent experimentally effective barrier heights and ideality factors. The zero-bias barrier height ( ) versus 1/2kT plot has been drawn to obtain evidence of a Gaussian distribution of the barrier heights and values of = 0.80 eV and = 114 mV for the mean barrier height and standard deviation have been obtained from the plot, respectively. The modified Richardson ln(I0/T2)- ( ) versus 1000/T plot has a good linearity over the investigated temperature range and gives the mean barrier height ( ) and Richardson constant (A*) values as 0.796 eV and 6.16 Acm-2K-2 respectively. The discrepancy between Schottky barrier heights obtained from I-V and C-V measurements is also interpreted.

Share and Cite:

D. Reddy, M. Reddy, N. Reddy and V. Reddy, "Schottky Barrier Parameters of Pd/Ti Contacts on N-Type InP Revealed from I-V-T And C-V-T Measurements," Journal of Modern Physics, Vol. 2 No. 3, 2011, pp. 113-123. doi: 10.4236/jmp.2011.23018.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1] E. H. Rhoderick and R. H. Williams, “Metal-Semiconductor Contacts,” 2nd Edition, Clarendon Press, Oxford, 1988.
[2] R. H. Williams and G. Y. Robinson, “Physics and Chemistry of III-V Compound Semiconductor Interfaces,” C. W. Wilmsen, Ed., Plenum Press, New York, 1985.
[3] R. T. Tung, “Recent Advances in Schottky Barrier Concepts,” Materials Science and Engineering: R, Vol. 35, No. 1-3, November 2001, pp. 1-138.
[4] K. Hattori and Y. Torii, “A New Method to Fabricate Au/n-type InP Schottky Contacts with an Interfacial Layer,” Solid-State Electronics, Vol. 34, No. 5, May 1991, pp. 527-531.
[5] Z. J. Horvath, V. Rakovics, B. Szentpali and S. Puspoki, “Schottky Junctions on n-Type InP for Zero Bias Microwave Detectors,” Physica Status Solidi C, Vol. 3, February 2003, pp. 916-921.
[6] T. S. Huang and R. S. Fang, “Barrier Height Enhancement of Pt/n-InP Schottky Diodes by P2S5/(NH4)2S Solution Treatment of the InP Surface,” Solid-State Electronics, Vol. 37, No. 8, August 1994, pp. 1461-1466.
[7] G. Eftekhari, “Electrical Characterization of Rapidly Annealed Ni and Pd/n-InP Schottky Diodes,” Semicon- ductor Science and Technology, Vol. 10, No. 8, May 1995, p. 1163.
[8] M. Soylu, B. Abay and Y. Onganer, “The Effects of Annealing on Au/Pyronine-B/MD n-InP Schottky Structure,” Journal of Physics and Chemistry of Solids, Vol. 71, No. 9, September 2010, pp. 1398-1403.
[9] Y. P. Song, R. L. Van Meirhaeghe, W. H. Laflere and F. Cardon, “On the Difference in Apparent Barrier Height as Obtained from Capacitance-Voltage and Current-Voltage- Temperature Measurements on Al/p-InP Schottky Barriers,” Solid-State Electronics, Vol. 29, No. 6, June 1986, pp. 633-638.
[10] J. H. Werner and H. H. Guttler, “Barrier Inhomogeneities at Schottky Contacts,” Journal of Applied Physics, Vol. 69, No. 3, February 1991, p. 1522.
[11] R. T. Tung, “Electron Transport at Metal-Semiconductor Interfaces: General Theory,” Physical Review B, Vol. 45, No. 23, June 1992, p. 13509.
[12] A. Gumus, A. Turut and N. Yalcin, “Temperature Dependent Barrier Characteristics of CrNiCo Alloy Schottky Contacts on n-Type Molecular-Beam Epitaxy GaAs,” Journal of Applied Physics, Vol. 91, No. 1, January 2002, p. 245.
[13] Y. G. Chen, M. Ogura and H. Okushi,“Temperature Dependence on Current-Voltage Characteristics of Nickel/ Diamond Schottky Diodes on High Quality Boron-Doped Homoepitaxial Diamond Film,” Applied Physics Letters, Vol. 82, No. 24, June 2003, p. 4367.
[14] M. K. Hudait, P. Venkateswaralu and S. B. Krupanidhi, “Electrical Transport Characteristics of Au/n-GaAs Schottky Diodes on n-Ge at Low Temperatures,” Solid- State Electronics, Vol. 45, No. 1, January 2001, pp. 133- 141.
[15] F. A. Padovani, “Semiconductors and Semimetals,” R. K. Willardson, A. C. Beer, Ed., Academic Press, New York, Vol. 7A, 1971.
[16] C. R. Crowell, “The Physical Significance of the T0 Anomalies in Schottky Barriers,” Solid-State Electronics, Vol. 20, No. 3, March 1977, pp. 171-175.
[17] R. T. Tung, J. P. Sullivan and F. Schrey, “On the Inhomogeneity of Schottky Barriers,” Materials Science and Engineering: B, Vol. 14, No. 3, August 1992, pp. 266-280.
[18] R. F. Schmitsdorf, T. U. Kampen and W. Monch, “Explanation of the Linear Correlation between Barrier Heights and Ideality Factors of Real Metal-Semiconductor Contacts by Laterally Nonuniform Schottky Barriers,” Journal of Vacuum Science & Technology B, Vol. 15, No. 4, July-August 1997, p. 1221.
[19] S. Zhu, R. L. van Meirhaeghe, C. Detavernier, F. Cardon, G. P. Ru, X. P. Qu and B. Z. Li, “Barrier Height Inhomogeneities of Epitaxial CoSi2 Schottky Contacts on n-Si (100) and (111),” Solid-State Electronics, Vol. 44, No. 4, April 2000, pp. 663-671.
[20] H. Cetin and E. Ayyildiz, “Temperature Dependence of Electrical Parameters of the Au/n-InP Schottky Barrier Diodes,” Semiconductor Science and Technology, Vol. 20, No. 6, May 2005, pp. 625-631.
[21] M. B. Reddy, A. A. Kumar, V. Janardhanam, V. Rajagopal Reddy and P. Narasimha Reddy, “Current–Voltage– Temperature (I–V–T) Characteristics of Pd/Au Schottky Contacts on n-InP (111),” Current Applied Physics, Vol. 9, No. 5, September 2009, pp. 972-977.
[22] M. Soylu and B. Abay, “Barrier Characteristics of Gold Schottky Contacts on Moderately Doped n-InP Based on Temperature Dependent I–V and C–V Measurements,” Microelectronic Engineering, Vol. 86, No. 1, January 2009, pp. 88-95.
[23] A. Ashok Kumar, V. Janardhanam, V. R. Reddy and P. Narasimha Reddy, “Evaluation of Schottky Barrier Parameters of Pd/Pt Schottky Contacts on n-InP (100) in Wide Temperature Range,” Superlattices and Microstructures, Vol. 45, No. 1, January 2009, pp. 22-32.
[24] F. E. Cimilli, H. Efeoglu, M. Saglam and A. Turat, “Temperature-Dependent Current-Voltage and Capacitance-Voltage Characteristics of the Ag/n-InP/In Schottky Diodes,” Journal of Material Science: Materials in Electronics, Vol. 20, February 2008, pp. 105-112.
[25] S. S. Naik and V. Rajagopal Reddy, “Analysis of Current-Voltage-Temperature (I-V-T) and Capacitance- Voltage-Temperature(C-V-T) Characteristics of Ni/Au Schottky Contacts on n-Type InP,” Superlattices and Microstructures, Vol. 48, No. 3, September 2010, pp. 330- 342.
[26] J. P. Sullivan, R. T. Tung, M. R. Pinto and W. R. Graham, “Electron Transport of Inhomogeneous Schottky Barriers: A Numerical Study,” Journal of Applied Physics, Vol. 70, No. 12, December 1991, p. 7403.
[27] S. Zeyrek, S. Altindal, H. Yuzer and M. Bulbul, “Current Transport Mechanism in Al/Si3N4/p-Si (MIS) Schottky Barrier Diodes at Low Temperatures,” Applied Surface Science, Vol. 252, No. 8, February 2006, pp. 2999-3010.
[28] S. K. Cheung and N. W. Cheung, “Extraction of Schottky Diode Parameters from Forward Current-Voltage Characteristics,” Applied Physics Letters, Vol. 49, No. 2, July 1986, p. 85.
[29] S. M. Sze, “Physics of Semiconductor Devices,” 2nd Edition, John Wiley and Sons, New York, 1981.
[30] S. Chand and J. Kumar, “Current Transport in Pd2Si/ n-Si(100) Schottky Barrier Diodes at Low Tempe- ratures,” Applied Physics A, Vol. 63, No. 2, March 1996, p. 171.
[31] N. Newman, M. V. Schilfgaarde, T. Kendelwicz, M. D. Williams and W. E. Spicer, “Electrical Study of Schottky Barriers on Atomically Clean GaAs(110) Surfaces,” Physical Review B, Vol. 33, No. 2, January 1986, p. 1146.
[32] Z. J. Horvath, “Comment on “Analysis of I-V Measurements on CrSi2 - Si Schottky Structures in a Wide Temperature Range,” Solid-State Electronics, Vol. 39, No. 1, January 1996, pp. 176-178.
[33] F. Pandovani and R. Stratton, “Field and Thermionic- Field Emission in Schottky Barriers,” Solid-State Electronics, Vol. 9, No. 7, July 1966, pp. 695-707.
[34] C. R. Crowell and V. L. Rideout, “Normalized Thermi- onic-Field (T-F) Emission in Metal-Semiconductor (Schottky) Barriers,” Solid-State Electronics, Vol. 12, No. 2, February 1969, pp. 89-105.
[35] Z. J. Horvath, V. Rakovics, B. Szentpali, S. Puspoki and K. Zdansky, “InP Schottky Junctions for Zero Bias Detector Diodes,” Vacuum, Vol. 71, No. 1-2, May 2003, pp. 113-116.
[36] J. Osvald, “New Aspects of the Temperature Dependence of the Current in Inhomogeneous Schottky Diodes,” Semiconductor Science and Technology, Vol. 18, No. 4, April 2003, p. L24.
[37] F. E. Jones, B. P. Wood, J. A. Myers, C. H. Daniels and M. C. Lonergan, “Current Transport and the Role of Barrier Inhomogeneities at the High Barrier n-InP Poly (Pyrrole) Interface,” Journal of Applied Physics, Vol. 86, No. 11, December 1999, p. 6431.
[38] M. K. Hudait, P. V. Venkateswaralu and S. B. Krupanidhi, “Electrical Transport Characteristics of Au/n- GaAs Schottky Diodes on n-Ge at Low Temperatures,” Solid-State Electronics, Vol. 45, No. 1, January 2001, pp. 133-141.
[39] J. H. Werner and H. H. Guttler, “Temperature Dependence of Schottky Barrier Heights on Silicon,” Journal of Applied Physics, Vol. 73, No. 3, February 1993, p. 1315.
[40] H. H. Guttler and J. H. Werner, “Influence of Barrier Inhomogeneities on Noise at Schottky Contacts,” Applied Physics Letters, Vol. 56, No. 12, March 1990, p. 1113.
[41] S. Zhu, R. L. Van Meirhaeghe, S. Forment, G. P. Ru, X. P. Qu and B. Z. Li, “Schottky Barrier Characteristics of Ternary Silicide Co1?xNixSi2 on n-Si(100) Contacts Formed by Solid Phase Reaction of Multilayer,” Solid- State Electronics, Vol. 48, No. 7, July 2004, pp. 1205- 1209.
[42] R. F. Schmitsdorf, T. U. Kampen and W. Monch “Correlation between Barrier Height and Interface Structure of Ag/Si(111) Schottky Diodes,” Surface Science, Vol. 324, No. 2-3, February 1995, pp. 249-256.
[43] L. E. Calvet, R. G. Wheeler and M. A. Reed, “Electron Transport Measurements of Schottky Barrier Inhomogeneities,” Applied Physics Letters, Vol. 80, No. 10, March 2001, p. 1761.
[44] Y. F. Tsay, B. Gong and S. S. Mitra, “Temperature Dependence of Energy Gaps of Some III-V Semiconductors,” Physical Review B, Vol. 6, No. 6, September 1972, p. 2330.

Copyright © 2024 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.