摘要
The growth character and microstructure of high-T_c supereonducting YBCO thin films deposited on vari- ous substrates have been studied by X-ray diffraction, TEM and SEM.The results show that when the substrate temperaturc is around 700～800℃ the films have a highly oriented texture with c-axis pependicular to the substrate. The structure of the single crystalline YBCO films grown epitaxially at optimal substrate tem- perature of 800℃ has been established by X-ray diffraction using Seemann-Bohlin geometry (SB). Brentano-Bragg geometry(BB),transmission Laue method and TEM. The lattice matching required for epitaxial growth is achievcd by azimuthal adjustment of the film plane with respect to the substrate plane. The sperior growth is demonstrated by film properties such as critical current density(2.4×10~6 A /cm^2,3.4× 10~6 A/cm^2 and 4.7×l0~6 A/cm^2) for films deposited on YSZ[(Zr(Y)O_2],SrTiO_3 and LaAIO_3 respectively at 77 K and zero fie1d.
The growth character and microstructure of high-T_c supereonducting YBCO thin films deposited on vari- ous substrates have been studied by X-ray diffraction, TEM and SEM.The results show that when the substrate temperaturc is around 700～800℃ the films have a highly oriented texture with c-axis pependicular to the substrate. The structure of the single crystalline YBCO films grown epitaxially at optimal substrate tem- perature of 800℃ has been established by X-ray diffraction using Seemann-Bohlin geometry (SB). Brentano-Bragg geometry(BB),transmission Laue method and TEM. The lattice matching required for epitaxial growth is achievcd by azimuthal adjustment of the film plane with respect to the substrate plane. The sperior growth is demonstrated by film properties such as critical current density(2.4×10~6 A /cm^2,3.4× 10~6 A/cm^2 and 4.7×l0~6 A/cm^2) for films deposited on YSZ[(Zr(Y)O_2],SrTiO_3 and LaAIO_3 respectively at 77 K and zero fie1d.
