Method for making polycrystalline thin film and associated oxide superconductor and apparatus therefor

An apparatus for making a polycrystalline thin film comprising:

• a deposition chamber for depositing a polycrystalline thin film on a substrate and for housing the following component devices;
• a feed spool for feeding a substrate in a longitudinal direction;
• a take-up spool for winding said substrate forwarded from said feed spool;
• a base holder disposed between said feed spool and said take-up spool for guiding said substrate while being in contact with a back surface of said substrate;
• a target disposed opposite to a front surface of said substrate being guided in said base holder for depositing particles emitted from said target;
• an ion source disposed opposite to said front surface for radiating an ion beam towards said front surface at an angle of incidence selected from a given range of angles;
• and
• a cooling device adapted to cool said substrate to a range within −150° C. to less than 100° C. for cooling said substrate through said base holder.