Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-12-01T09:16:31.691Z Has data issue: false hasContentIssue false
  • English
  • Français

Optical Absorption at Digitally and Continuously Graded Indium Gallium Nitride Schottky Barriers

Published online by Cambridge University Press:  01 February 2011

Choudhury Jayant Praharaj
Choudhury Jayant Praharaj*
Affiliation:
[email protected], Unaffiliated, Unaffiliated, 1901 Halford Avenue, Apt 74, Santa Clara, CA, 95051, United States
Get access

Abstract

We present numerical calculations of the optical absorption characteristics of graded Indium Gallium Nitride Schottky Barriers, and study their implications for photovoltaic and photodetector applications. We consider the two cases of digital and continuous grading because of their different effects on the collection of photo-generated carriers due to band discontinuities. Composition grading can achieve desired spectral response between the ranges of 0.7 eV and 3.43 eV afforded by the Indium Gallium Nitride alloy system. The presence of spontaneous and piezoelectric polarizations in this material system adds bulk and/or interface bound charges in graded layers. This has a non-trivial effect on the band profile seen by the photo-generated carriers. The layer thicknesses needed for optimal absorption characteristics are well above the theoretical critical thickness limits reported in the literature for abrupt heterojunctions. However, experimental data about critical thicknesses is scarce, especially for graded compositions. Therefore, we calculate the characteristics of the Schottky barrier for the case of spontaneous polarization only and also for the case of both spontaneous and piezoelectric polarization assuming no relaxation. The low or even negative Schottky barrier heights at low Gallium composition necessitates the use of high Gallium composition layers next to the metal, in order to suppress the excessive dark currents

Keywords

III-Vopticalphotovoltaic
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1012: Symposium Y – Thin-Film Compound Semiconductor Photovoltaics-2007 , 2007 , 1012-Y12-34
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Trybus, E, Namkoong, G., Henderson, W., Burnham, S., Doolittle, W. A., Cheung, M. and Cartwright, A., Journal of Crystal Growth, 288, 218–224 ( 2006 )Google Scholar
2. Wu, J., Walukiewicz, W., Yu, K. M., Shan, W., Ager, J. W. III, Haller, E. E., Lu, H., Schaff, W. J., Metzger, W. K. and Kurtz, S., J. Appl. Phys, 94, 6477–6482 ( 2003 )Google Scholar
3. Zhou, J. J., Jiang, R. L., Wen, B., Liang, L. Y., Ji, X. L., Shen, B., Zhang, R. and Zheng, Y. D., J. Appl. Phys, 95, 5925–5927 ( 2004 )Google Scholar
4. Chang, S. J., Yu, C. L., Chen, C. H., Chang, P. C. and Huang, K. C., J. Vac. Sci. Technol. A 24 ( 3 ), 637–640 ( 2006 )Google Scholar
5. Chang, S. J., Kuan, T.M., Ko, C. H., Su, Y. K., Webb, J. B., Bardwell, J. A., Liu, Y., Tang, H., Lin, W. J., Cherng, Y. T. and Lan, W. H., Solid State Electronics, 47, 2023–2026 ( 2003 )Google Scholar
6. Chiou, Y., IEEE Electron Device Letters, 26, 172–174 ( 2005 )Google Scholar
7. Ohsawa, J., Kozawa, T., Ishiguro, O. and Itoh, H., Japanese Journal of Applied Physics, 45, L435– L437 ( 2006 )Google Scholar
8. Su, Y., Chiou, Y., Juang, F., Chang, S. and Sheu, J., Japanese Journal of Applied Physics, 40, 2996–2999 ( 2001 )Google Scholar
9. Chen, Q., Appl. Phys. Lett., 70, 2277–2279 ( 1997 )Google Scholar
10. Monroy, E., Calle, F., Munoz, E., Omnes, F., Gibart, P. and Munoz, J. A., Appl. Phys. Lett., 73, 2146–2148 ( 1998 )Google Scholar
11. Kawashima, T., Yoshikawa, H., Adachi, S., Fuke, S. and Ohtsuka, K., J. Appl. Phys, 82, 3528–3535 ( 1997 )Google Scholar
12. Schley, P., Goldhahn, R., Winzer, A. T., Gobsch, G., Cimalla, V., Ambacher, O., Rakel, M., Cobet, C., Esser, N., Lu, H. and Schaff, W. J., Physica Status Solidi ( b ), 243, 1572–1576 ( 2006 )Google Scholar
13. Muth, J. F., Lee, J. H., Shmagin, I. K., Kolbas, R. M., Casey, H.C., Keller, B. P., Mishra, U. K. and DenBaars, S. P., Appl. Phys. Lett., 71, 2572–2574 ( 1997 )Google Scholar
14. Goldhahn, R., Schley, P., Winzer, A. T., Rakel, M., Cobet, C., Esser, N., Lu, H. and Schaff, W. J., Journal of Crystal Growth, 288, 273–277 ( 2006 )Google Scholar
15. Baldanzi, A., Bellotti, E. and Goano, M., Physica Status Solidi ( b ), 228, 425–428 ( 2006 )Google Scholar
16. Jackson, J. D., Classical Electrodynamics, John Wiley and Sons ( 1999 )Google Scholar
17. Bernardini, F. and Fiorentini, V., Physical Review B (Condensed Matter and Materials Physics), 64 ( 2001 )Google Scholar
18. Ambacher, O., Majewski, J., Miskys, C., Link, A., Hermann, M., Eickoff, M., Stutzmann, M., Bernardini, F., Fiorentini, V., Tilak, V., Schaff, B. and Eastman, L. F., Journal of Physics: Condensed Matter, 14, 339–434 ( 2002 )Google Scholar
19. Pereira, S.. Correia, M. R., Pereira, E., Trager-Cowan, C., Sweeney, F., O'Donnell, K. P., Alves, E., Franco, N. and Sequeira, A. D., Appl. Phys. Lett, 81, 1207 ( 2002 )Google Scholar
20. Bandic, Z. Z., Bridger, P. M., Piquette, E. C. and McGill, T. C., Appl. Phys. Lett., 72, 3166–3168 ( 1998 )Google Scholar
21. Bandic, Z. Z., Bridger, P. M., Piquette, E. C. and McGill, T. C., Solid State Electronics, 44, 221–228 ( 2000 )Google Scholar
22. Chen, F., Cartwright, A. N., Lu, H. and Schaff, W. J., Appl. Phys. Lett. 87, 212104, ( 2005 )Google Scholar