Annealing Effect on the Structural and Optical Properties of Sputter-Grown Bismuth Titanium Oxide Thin Films

Materials

José E. Alfonso²  Jhon J. Olaya²  Claudia M. Bedoya-Hincapié²  Johann Toudert¹ 

[1] Laser Processing Group, Instituto de Optica, CSIC, c/Serrano 121, Madrid 28006, Spain; E-Mails:;Grupo de ciencia de materiales y superficies, Universidad Nacional de Colombia, Bogotá AA 14490, Colombia; E-Mails:

关键词: thin films;    optical characterization;    refractive index;   

DOI  :  10.3390/ma7053427

来源: mdpi

【 摘 要 】

The aim of this work is to assess the evolution of the structural and optical properties of Bi_xTi_yO_z films grown by rf magnetron sputtering upon post-deposition annealing treatments in order to obtain good quality films with large grain size, low defect density and high refractive index similar to that of single crystals. Films with thickness in the range of 220–250 nm have been successfully grown. After annealing treatment at 600 °C the films show excellent transparency and full crystallization. It is shown that to achieve larger crystallite sizes, up to 17 nm, it is better to carry the annealing under dry air than under oxygen atmosphere, probably because the nucleation rate is reduced. The refractive index of the films is similar under both atmospheres and it is very high (n =2.5 at 589 nm). However it is still slightly lower than that of the single crystal value due to the polycrystalline morphology of the thin films.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland