수정된 TFA-MOD법에 의한 $SmBa_{2}Cu_{3}O_{7-{\delta}}$ 박막의 제조

Fabrication of High-Quality $SmBa_{2}Cu_{3}O_{7-{\delta}}$ Thin Films by a Modified TFA-MOD Process

We report a successful fabrication of high-quality $SmBa_{2}Cu_{3}O_{7-{\delta}}$ (SmBCO) thin films on $LaAlO_3$(LAO)(100) single crystalline substrates by a modified TFA-MOD method. After the pyrolysis heat treatment of spin-coated films up to $400^{\circ}C$, SmBCO films were fired at various temperatures ranging from 810 to $850^{\circ}C$ in a reduced oxygen atmosphere (10 ppm $O_2$ in Ar). Optimally processed SmBCO films exhibited the zero-resistance temperature ($T_{c,zero}$) of 90.2 K and the critical current density ($J_c$) of $0.8\;MA/cm^2$ at 77K in self-field. Compared with the $J_c$ values (normally, > $2\;MA/cm^2$ at 77 K) of MOD-TFA processed YBCO films, rather depressed $J_c$ values in SmBCO films are most probably attributed to the existence of ${\alpha}$-axis oriented grains.