SPUTTER DEPOSITION OF YBA2CU3O7-X THIN-FILMS WITH LOW GAS-PRESSURE

Thin films of YBa2Cu3O7-xhave been prepared by rf-magnetron sputtering using a single oxide target with a low operating gas pressure of 0.5 Pa at which almost all the sputtered atoms reach the substrate without colliding with the gas. In spite of the low oxygen partial pressure of 0.25 Pa, sufficient oxygen was supplied to the film during the deposition to form the superconducting phase on a MgO(100) substrate. The Tcof the as-grown film rose with the increase of the substrate temperature and reached 83 K at 650°C. Thanks to the high reactivity and high kinetic energy of the depositing atoms, superconducting films with excellent crystallinity were obtained over a wide range of the substrate temperature between 525 and 650°C despite the high deposition rate of 2 Å/s, and the 123phase was formed even at 500°C. © 1990 IOP Publishing Ltd.