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Epitaxial YBa 2 Cu 3 O 7 (Y123) films were obtained by metal-organic deposition (MOD) using a simple, low-cost vacuum technique without gas flowing. The total pressure and oxygen partial pressure in the furnace were controlled to be 10 kPa and 10 Pa, respectively, by evacuation with a rotary pump followed by refilling with a mixture of O 2 and N 2 (O 2 content: 1000 ppm). XRD analyses exhibited that -axis-oriented epitaxial Y123 films have successfully been obtained on CeO 2 -buffered YSZ (100) (CbZ) and CeO 2 -buffered sapphire (012) (CbS) substrates. In-plane alignments of these films were as high as that of the CeO 2 buffer layer. The film on the CbZ demonstrated a high critical current density c of 2 1 MA cm 2 at 77 K all over the film; the fluctuation of c being within 10% of the average. Inductive c measurement showed a very sharp peak with c = 90 5 K. Inductive-c and c of the Y123 film on CbS were 1.1 MA cm 2 and 89.6 K, respectively, whereas the c of the Y123 film on LaAlO 3 was lower than 77 K owing to the occurrence of the -axis grains.Index Terms-Critical current density, epitaxial Y123 film, metal-organic deposition, vacuum.

A microfabrication method to produce YBa2Cu3O7-δ (YBCO) was investigated using the metal organic deposition (MOD) process with electron beam (EB) irradiation. EB irradiation causes decomposition of the C–H and –COO– bonds and desorption of oxygen atoms in the metal octylate precursors. Therefore, oxidation of metal atoms could become harder for the MOD with EB irradiation than for the conventional MOD because of lack of oxygen, and consequently a longer prefiring time is required to ensure oxidation of the metal atoms. Additionally, the heating rate for crystallization was increased to improve film coverage. Finally YBCO film with superconductivity was successfully obtained.

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