Sol-gel waveguide thin film of YBO3: preparation and characterization

Pure and Eu3+ ions doped YBO3 waveguide thin films were dip-coated for the first time through sol-gel route. The quality of the film depends significa ntly on the dip-coating conditions, especially on environment humidity. We succeeded to prepare crack free thick films with 16 layers and thickness of about 850 nm. Tt is found that the coating process obeys a two-step kineti cs. The films were characterized by different methods, such as m-line spect roscopy, X-ray diffraction, electron microscopy and waveguide fluorescence spectroscopy (WFS). When the annealing temperature is lower than 600 degree s C the film is amorphous and has good waveguide performance. The attenuati on of the propagation we have reached is about 0.5 dB/cm. The film starts t o crystallize at 700 degrees C. The waveguide performance of the him decrea ses dramatically with the annealing temperature above 700 degrees C, The re sult of WFS also indicates that this new kind of thin film is a good host m aterial for active dopants. Our preliminary results show that the new thin film is of great potential for future application in optoelectronics. (C) 2 000 Elsevier Science B.V. All rights reserved.