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Photosensitive Capacitance Effect In High-purity Semi-insulating 4H-SiC

Published online by Cambridge University Press:  18 June 2014

Joseph Register ,
Stephen E. Saddow  and
Kevin Boulais
Joseph Register
Affiliation:
University of South Florida, Dept. of Electrical Engineering, 4202 E. Fowler Ave., Tampa, FL 33620, USA
Stephen E. Saddow
Affiliation:
University of South Florida, Dept. of Electrical Engineering, 4202 E. Fowler Ave., Tampa, FL 33620, USA
Kevin Boulais
Affiliation:
Naval Surface Warfare Center, Dahlgren, VA
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Abstract

We demonstrate a novel optically tunable photosensitive capacitor (PSC) made from high-purity semi-insulating 4H-SiC. Photosensitive capacitors can provide continuously variable reactive tuning in RF circuitry or enable capacitive-optical sensing applications. Unlike varactors, PSCs often do not require a DC bias voltage to operate. To demonstrate the effect, we fabricated several 1cm x 1cm square photocapacitor devices from bulk material using metal-evaporated Ti/Au contacts using a simple planar parallel-gap geometry. IV curves were taken of the devices using an HP-4145B semiconductor parameter analyzer to verify Schottky behavior as a function of DC bias. The samples were then illuminated with pulsed below-bandgap 470 nm and 590 nm high intensity LED light sources. The resulting data demonstrated an increase in capacitance, Cs, and a drop in resistance, Rs, with increasing optical intensity incident on the device. The observed shifts in both Cs and Rs were repeatable. At a measurement frequency of 33 kHz. Cs increased from its nominal value of 186.7 pF to 575.6 pF while Rs dropped from 150.0 kΩ to 22.4 kΩ. This demonstrates the existence of the photocapacitance effect in high-purity semi-insulating 4H-SiC and thus warrants further investigation. The underlying phenomenon of the effect is suspected to be light interaction with the dominant deep level traps through the Shockley–Read–Hall (SRH) recombination mechanism.

Keywords

semiconductingopticaldefects
Type
Articles
Information
MRS Online Proceedings Library (OPL) , Volume 1693: Symposium DD – Silicon Carbide–Materials, Processing and Devices , 2014 , mrss14-1693-dd06-18
Copyright
Copyright © Materials Research Society 2014 

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References

Kumar, R. J., Borrego, J. M., Gutmann, R. J., Jenny, J. R., Malta, D. P., Hobgood, H. M., and Carter, C. H., “Microwave photoconductivity decay characterization of high-purity 4H-SiC substrates,” J. Appl. Phys., vol. 102, no. 1, p. 013704, Jul. 2007.CrossRefGoogle Scholar
Horsfall, A., “Review of ‘Advances in Silicon Carbide Processing and Applications’ 1st Edition by Steven E. Saddow and Anant Agarwal,” BioMedical Engineering OnLine, vol. 4. BioMed Central, p. 33, 2005.CrossRefGoogle Scholar
Klein, P. B., Shanabrook, B. V., Huh, S. W., Polyakov, A. Y., Skowronski, M., Sumakeris, J. J., and O’Loughlin, M. J., “Lifetime-limiting defects in n[sup −] 4H-SiC epilayers,” Appl. Phys. Lett., vol. 88, no. 5, p. 052110, Feb. 2006.CrossRefGoogle Scholar
Son, N., Carlsson, P., Ul Hassan, J., Magnusson, B., and Janzén, E., “Defects and carrier compensation in semi-insulating 4H-SiC substrates,” Phys. Rev. B, vol. 75, no. 15, pp. 1–8, 2007.CrossRefGoogle Scholar
Singh, S. and Cooper, J. A., “Bipolar Integrated Circuits in 4H-SiC,” IEEE Trans. Electron Devices, vol. 58, no. 4, pp. 1084–1090, Apr. 2011.CrossRefGoogle Scholar
Mitchel, W. C., Perrin, R., Goldstein, J., Roth, M., Smith, S. R., Solomon, J. S., Evwaraye, A. O., Hobgood, H. M., Augustine, G., and Balakrishna, V., “The 1.1 eV deep level in 4H-SiC,” in Semiconducting and Insulating Materials, 1998. (SIMC-X) Proceedings of the 10th Conference on, 1998, pp. 283–286.CrossRefGoogle Scholar
Løvlie, L. S., “Intrinsic bulk and interface defects in 4H silicon carbide.” 29-Jan-2013.Google Scholar
Mitchel, W. C., Mitchell, W. D., Smith, H. E., Landis, G., Smith, S. R., and Glaser, E. R., “Compensation mechanism in high purity semi-insulating 4H-SiC,” J. Appl. Phys., vol. 101, no. 5, p. -, 2007.CrossRefGoogle Scholar
Dueñas, S., Castán, E., de Dios, A., Bailón, L., Barbolla, J., and Pérez, A., “Characterization of the EL2 center in GaAs by optical admittance spectroscopy,” J. Appl. Phys., vol. 67, no. 10, p. 6309, May 1990.CrossRefGoogle Scholar
Boulais, K. A., Santiago, F., Wick, P. L., Mejeur, J. M., Rayms-Keller, A., Lowry, M. S., Long, K. J., and Sessions, W. D., “Circuit Analysis of Photosensitive Capacitance in Semi-Insulating GaAs,” IEEE Trans. Electron Devices, vol. 60, no. 2, pp. 793–798, Feb. 2013.CrossRefGoogle Scholar
Goswami, A. and Goswami, A. P., “Dielectric and optical properties of ZnS films,” Thin Solid Films, vol. 16, no. 2, pp. 175–185, May 1973.CrossRefGoogle Scholar
Sakr, G. B. and Yahia, I. S., “Effect of illumination and frequency on the capacitance spectroscopy and the relaxation process of p-ZnTe/n-CdMnTe/GaAs magnetic diode for photocapacitance applications,” J. Alloys Compd., vol. 503, no. 1, pp. 213–219, Jul. 2010.CrossRefGoogle Scholar
Levinshtein, M., Rumyantsev, S., and Shur, M., Properties of advanced semiconductor materials : GaN, AlN, InN, BN, SiC, SiGe. Wiley, 2001.Google Scholar
Wijesundara, M. B. J. and Azevedo, R., Silicon Carbide Microsystems for Harsh Environments, vol. 22. New York, NY: Springer New York, 2011.CrossRefGoogle Scholar
Lo̸vlie, L. S. and Svensson, B. G., “Enhanced annealing of implantation-induced defects in 4H-SiC by thermal oxidation,” Appl. Phys. Lett., vol. 98, no. 5, p. 052108, Feb. 2011.CrossRefGoogle Scholar
Kato, M., Tanaka, S., Ichimura, M., Arai, E., Nakamura, S., Kimoto, T., and R. Pässler, “Optical cross sections of deep levels in 4H-SiC,” J. Appl. Phys., vol. 100, no. 5, p. 053708, Sep. 2006.CrossRefGoogle Scholar
Liou, G., Lin, P., Yen, H., Yu, Y., and Chen, W., “Flexible Nanocrystalline-Titania / Polyimide Hybrids with High Refractive Index and Excellent Thermal Dimensional Stability,” Polymer (Guildf)., vol. 48, pp. 1433–1440, 2010.Google Scholar
Levinshtein, M. E., Rumyantsev, S. L., and Shur, M., Properties of advanced semiconductor materials : GaN, AlN, InN, BN, SiC, SiGe. Wiley, 2001, pp. 93–148.Google Scholar
Mitchel, W. C., Perrin, R., Goldstein, J., Saxler, A., Roth, M., Smith, S. R., Solomon, J. S., and Evwaraye, A. O., “Fermi level control and deep levels in semi-insulating 4H–SiC,” J. Appl. Phys., vol. 86, no. 9, p. 5040, Nov. 1999.CrossRefGoogle Scholar
Chandrashekhar, M. V. S., Chowdhury, I., Kaminski, P., Kozlowski, R., Klein, P. B., and Sudarshan, T., “High Purity Semi-Insulating 4H-SiC Epitaxial Layers by Defect-Competition Epitaxy: Controlling Si Vacancies,” Appl. Phys. Express, vol. 5, no. 2, p. 025502, Feb. 2012.CrossRefGoogle Scholar
Kumar, S., “Simulation of Trapping Effects in 4H-Silicon Carbide Metal Semiconductor Field Effect Transistor (4H-SiC MESFET).” 06-Jun-2011.Google Scholar