Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524
Qrcode

Article

J. Korean Phy. Soc. 2009; 55(3(2)): 1272-1277

Published online September 15, 2009     https://doi.org/10.3938/jkps.55.1272

Copyright © The Korean Physical Society.

Effect of Deposition Angle on the Optical and the StructuralProperties of Ta$_2$O$_5$ Thin Films Fabricated by Using GlancingAngle Deposition

K.M. Sobahan, YongJun Park, ChangKwon Hwangbo

Abstract

In this paper, the effect of deposition angle on the optical and thestructural properties of Ta$_2$O$_5$ thin films fabricated by usingelectron beam evaporation with a glancing angle deposition (GLAD)technique is reported. The refractive index and the porosity atvarious deposition angles are studied. We see that the refractiveindex decreases and the porosity increases with increasingdeposition angle. The calculated in-plane birefringence of GLADTa$_2$O$_5$ films shows a maximum value of 0.04 at a depositionangle of 70$^circ$. The microstructure and the morphology are alsoinvestigated by using scanning electron microscope (SEM). Thecross-sectional SEM images illustrate a highly orientedmicrostructure composed of slanted columns and voids due to theshadowing effect and limited adatom diffusion. Therefore, theglancing angle deposition technique is an original way to controlthe columnar microstructure with an enhanced birefringence.

Keywords: Glancing angle deposition, Ta$_2$O$_5$ thin films, Birefringence