SURFACE MODIFICATION OF BI-SR-CA-CU-O FILMS DEPOSITED INSITU BY RADIO-FREQUENCY PLASMA FLASH EVAPORATION WITH A SCANNING TUNNELING MICROSCOPE

The surface modifications of as-grown superconducting Bi-Sr-Ca-Cu-O (BSCCO) films prepared by radio frequency plasma flash evaporation were carried out with a scanning tunneling microscope (STM). The as-grown films were identified as highly c-axis-oriented, low T(c) (80 K) phase Bi2Sr2Ca1Cu2O(x) with some residue such as (Sr,Ca)3Cu5O(x) from x-ray diffraction patterns. The as-grown film deposited at about 750-degrees-C exhibited a superconducting critical temperature T(c) of 76 K and a critical current density J(c) of 8.8 X 10(4) A/cm2 Under zero magnetic field at 27 K. The nanometer-size surface modifications between 2 and 50 nm, especially layered etching, of the prepared BSCCO films were successfully performed by using a STM in air.