Surface modification of Bi-Sr-Ca-Cu-O films deposited in situ by radio frequency plasma flash evaporation with a scanning tunneling microscope

Abstract
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 Tc (80 K) phase Bi2Sr2Ca1Cu2Ox with some residue such as (Sr,Ca)3Cu5Ox from x‐ray diffraction patterns. The as‐grown film deposited at about 750 °C exhibited a superconducting critical temperature Tc of 76 K and a critical current density Jc of 8.8×104 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.