New method for preparing extremely thin Bi2Sr2Ca1Cu2Ox ribbon-like films on silver substrates and their superconducting properties

We have developed a simple technique to grow ribbon-like single crystalline films of Bi-2212 on Ag substrates. The process is performed under ambient pressure only by heating the Bi-2212 pellet on the edge of the substrates. The ribbons are extremely thin and are stuck firmly to the substrates, resu lting in the formation of a new type of composite of Bi-2212 ribbons/Ag. Th e formation of the ribbons was studied by observing their growth with a hig h-temperature microscope. In situ observation with the microscope revealed that most of the ribbons grew during 10 min of the plateau at 905 degrees C . The ribbon-like films showed the superconducting transition with an onset temperature of similar to 80 K. Observation with a high-temperature optica l microscope revealed that the ribbon crystals grew rapidly, (C) 2000 Elsev ier Science B.V. All rights reserved.