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Optical Thin Films with Very Low Refractive Index and Their Application in Photonics Devices

Published online by Cambridge University Press:  26 February 2011

Jingqun Xi ,
Jong Kyu Kim ,
Dexian Ye ,
Jasbir S. Juneja ,
T.-M. Lu ,
Shawn-Yu Lin  and
E. F. Schubert
Jingqun Xi
Affiliation:
xij@rpi.edu, Rensselaer Polytech Institute, Physics, Applied Physics, & Astronomy, CII 8231, Future Chips Constellation,, 110 8th Street, RPI,, Troy, NY, 12180, United States
Jong Kyu Kim
Affiliation:
kimj4@rpi.edu, Rensselaer Polytechnic Institute, Department of Electrical, Computer, & Systems Engineering
Dexian Ye
Affiliation:
yed@rpi.edu, Rensselaer Polytechnic Institute, Department of Physics, Applied Physics, & Astronomy
Jasbir S. Juneja
Affiliation:
juneja@rpi.edu, Rensselaer Polytechnic Institute, Department of Chemical & Biological Engineering
T.-M. Lu
Affiliation:
lut@rpi.edu, Rensselaer Polytechnic Institute, Department of Physics, Applied Physics, & Astronomy
Shawn-Yu Lin
Affiliation:
sylin@rpi.edu, Rensselaer Polytechnic Institute, Department of Physics, Applied Physics, & Astronomy
E. F. Schubert
Affiliation:
EFschubert@rpi.edu, Rensselaer Polytechnic Institute, Department of Electrical, Computer, & Systems Engineering
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Abstract

The refractive index contrast in dielectric multilayer structures, optical resonators and photonic crystals is an important figure of merit, which creates a strong demand for high quality thin films with a very low refractive index. SiO2 nano-rod layers with low refractive indices n = 1.08, the lowest ever reported in thin-film materials, is grown by oblique-angle e-beam deposition of SiO2 with vapor incident angle 85 degree. Scanning electron micrographs reveal a highly porous columnar structure of the low-refractive-index (low-n) film. The gap between the SiO2 nano-rods is ≤50 nm, i.e. much smaller than the wavelength of visible light, and thus sufficiently small to make scattering very small. Optical micrographs of the low-n film deposited on a Si substrate reveal a uniform specular film with no apparent scattering. The unprecedented low index of the SiO2 nano-rod layer is confirmed by both ellipsometry measurements and thin film interference measurements. A single-pair distributed Bragg reflector (DBR) employing the SiO2 nano-rod layer is demonstrated to have enhanced reflectivity, showing the great potential of low-n films for applications in photonic structures and devices.

Keywords

optical propertiesnanoscalescanning electron microscopy (SEM)
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 901: Symposium R – Assembly at the Nanoscale – Toward Functional Nanostructured Materials , 2005 , 0901-Ra11-29-Rb11-29
Copyright
Copyright © Materials Research Society 2006

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References

1 Streubel, K., Rapp, S., André, J., and Chitica, N., Elec. Lett. 32, 1369 (1996).Google Scholar
2 Ho, S.T., McCall, S. L., Slusher, R. E., Pfeiffer, L. N., West, K. W., Levi, A. F. J., Blonder, G. E., and Jewell, J. L., Appl. Phys. Lett. 57, 1387 (1990).Google Scholar
3 Temelkuran, B., Hart, S. D., Benoit, G., Joannopoulos, J. D., and Fink, Y., Nature 420, 650 (2002).Google Scholar
4 Xi, J.Q., Ojha, M., Cho, W., Plawsky, J. L., Gill, W. N., Gessmann, Th., and Schubert, E. F., Opt. Lett. 30, 1518 (2005).Google Scholar
5 Xi, J.Q., Ojha, M., Plawsky, J. L., Gill, W. N., Kim, J. K., and Schubert, E. F., Appl. Phys. Lett. 87, 031111 (2005).Google Scholar
6 Nitta, S. V., Pisupatti, V., Jain, A., Wayner, P. C. Jr., Gill, W. N., and Plawsky, J. L., J. Vac. Sci. Technol. B 17, 205 (1999).Google Scholar
7 Jain, A., Rogojevic, S., Ponoth, S., Agarwal, N., Matthew, I., Gill, W. N., Persans, P., Tomozawa, M., Plawsky, J. L., and Simonyi, E., Thin Solid Films 398–399, 513 (2001).Google Scholar
8 van de Waterbeemd, J. G. W., and van Oosterhout, G. W., Philips Res. Repts. 22, 375 (1967).Google Scholar
9 Lakhtakia, A., Messier, R., Sculptured Thin Films: Nanoengineered Morphology and Optics, (SPIE, Washington, USA 2005).Google Scholar
10 Robbie, K., Friedrich, L. J., Dew, S. K., Smy, T., and Brett, M. J., J. Vac. Sci. Technol. A 13, 1032 (1995).Google Scholar
11 Robbie, K., and Brett, M. J., J. Vac. Sci. Technol. A 15, 1460 (1997).Google Scholar
12 Vick, D., Friedrich, L. J., Dew, S. K., Brett, M. J., Robbie, K., Seto, M., and Smy, T., Thin Solid Films 339, 88 (1999).Google Scholar
13 Kaminska, K., and Robbie, K., Appl. Opt. 43, 1570 (2004).Google Scholar