Investigation Of Amorphous Y₂O₃ Thin Film Preparation Using Chemical Solution Deposition

YBa2Cu3O7-x(YBCO) HTS coated conductor has been widely used in the field of electric power cables, generators, fault current limiters, superconducting magnetic energy storage systems, transformers, superconducting rotating machines and so on.Ion-beam assisted deposition(IBAD) biaxial texture magnesium oxide route serves as a mainstreamapproach to obtain high-performance YBCO coated conductor with the advantages of about 10 nm thickness IBAD-MgO film getting excellent biaxial texture, dramatically reducing the cost and time of the process, broadening the range of metal substrates choices. In this dissertation, we research the importance of preparation of substrates for IBAD-MgO, by using a chemical solution deposition planarization method(SDP) for fabrication of an amorphous oxide layer to provide commercial nickelalloy with nanoscale surface flatness. Amorphous oxide layer has three roles: barrier layer, polishing, nucleation layer. Compared with chemical mechanical polishing and electropolishing, SDP method is more environmentally friendly, simpler and cost savings.Focus on the process of preparation of amorphous Y2O3 films with dip-coating method. Investigate the selection of the solvent, solute, additives tocarry out the stabilized Y2O3 precursor solution. Factors which include the temperature, concentration, numbers of layers, pulling speed, mechanical devices, crack, crystallization, effected the roughness of Y2O3 film. Amorphous Y2O3 films were prepared, resulting RMS roughness of 0.4 nm and 5.2 nm from in 5×5 μm2and 20×20 μm2, respectively. Fabricate 20m-length better uniformity amorphous yttrium oxide substrate with smooth surface to extent that root mean square(RMS) roughness is below 2 nm. After the deposition of IBAD-MgO, in-plane and out-plane of full width at half-maximum(FWHM) were 6° and 3.5°. Texture of IBAD-MgO are sensitive to the quality of the Y2O3 amorphous thin film. When RMS is from 0.8 nm to 3.6 nm, surface RMS roughness within this range affects the out-plane textureof MgO little, however, with increasing RMS, the FWHM of in-plane texture increases dramatically.Research the preparation of amorphous thin film Y2O3-Al2O3(Y-Al-O), which having a high crystallization temperature and having access to adjust the ratio of Y and Al. With the decrease in the ratio of the precursor solution of Y and Al, the Al content in the deposited film is increased accordingly. We prepared Y0.9-Al0.1Oy,Y0.8-Al0.2Oy,Y0.7-Al0.3Oy(three ratios of Y-Al-O films), RMS being 0.42 nm, 0.62 nm, 0.89 nm, respectively.