Study of crystallization of LiNbO3films from metal alkoxides

✍ Scribed by S. Hirang; T. Yogo; K. Kikuta; Y. Isobe; S. Ono

• Book ID: 104735185
• Publisher: Springer
• Year: 1993
• Tongue: English
• Weight: 564 KB
• Volume: 28
• Category: Article
• ISSN: 0022-2461
• DOI: 10.1007/bf00351252

✦ Synopsis

The crystallization process of epitaxial LiNb03 films on sapphire (0001 ) substrates was investigated by Raman microprobe spectroscopy. LiNb03 gel films were prepared by the sol-gel method using metal alkoxide precursors on sapphire (0 0 01 ) substrates and heat treated at various temperatures below 500 ~ to produce epitaxial LiNbOa films. Analyses by electron spectroscopy for chemical analysis and SEM revealed LiNb03 films were stoichiometric and homogeneous. Raman spectra of the film prepared at 250~ indicated that the Nb06 octahedral coordination structure in LiNb03 began to form as the initial state of crystallization. As the heat-treatment temperature was raised, the Raman bands became sharper and increased in spectral intensity and were seen to be the characteristic Raman bands of crystalline LiNb03. Refractive indices of the obtained films indicated appropriate values. As a method to crystallize the more highly preferred orientation to (0 0 6) LiNbOa film at relatively low temperature, the formation of an underlayer film from diluted solution prior to multiple dip-coating, was found to be very promising.