abstract
One of the most popular techniques to fabricate low-loss optical waveguides is the use of zinc (Zn) ions by thermally diffusing them into lithium niobate (LN) crystal. Along this line the fabrication procedure involving lower temperatures and shorter times of diffusion would be more desirable. To this end we report a new procedure using advantages based on the DC-Magnetron sputtering technique through a 3-step waveguide fabrication process in X-cut LN; the first step was sputtering 150 nm thick Zn layer on 400 K hot LN substrate; after this, an immediate oxidation of deposited Zn layer has been done just for 10 min. in 450A degrees C. The final step was thermal diffusion of Zn into LN in a variety of times (1-3 h) and temperatures (600-800A degrees C). All probable changes have been characterized by XRD, RBS and double beam Spectrophotometer. Using the advantages of DC-Magnetron sputtering and simultaneous increase of substrate temperature, combined with an immediate oxidation step before final annealing; the encouraging results of RBS analysis revealed that the whole amount of Zn has diffused with a good gradient after annealing just for 3 h at 750A degrees C; and also the comparative analysis of as-received and diffused LN demonstrated good stability in its optical and structural properties.
keywords
FILMS
subject category
Materials Science; Physics
authors
Aghli-Moghadam, L; Baghizadeh, A; Nabiyouni, G; Farashiani, A; Zendehnam, A
our authors
Ali Baghi Zadeh
Post-Doc Fellowshipacknowledgements
This research has been carried out under the financial support by the Iran Telecommunication Research Centre (ITRC) under project 15373. The authors would like to thank Dr. Lamehi Rachti for his support in Van de Graaff Laboratory, Nuclear Science School, Nuclear Science & Technology Research Institute, Tehran, Iran.