Growth of Bi2Sr2CaCu2Oy single crystals by a self-flux method using precursors

We describe the preparation of Bi2Sr2CaCu2Ox (Bi-2212) single crystals by a self-flux method using a SrBiOy precursor and two different forms of Ca-Cu-O precursors. The precursors SrBiOy, Ca-Cu-O(1) and Ca-Cu-O(2) were produced by sintering at 800 degrees C, 800-950 degrees C and higher than 950 degrees C, respectively. We found that using these precursors lowered the growth temperature necessary to produce large Bi-2212 single crystals by about 100 degrees C as compared with starting without precursors, and that the Bi-2212 single crystals prepared at 940 degrees C showed a critical transition temperature of 91K. In addition, the advantages of using the precursor containing Ca2CuOz to that containing CaCu2Ow for crystal growth are given. (C) 1999 Elsevier Science B.V. All rights reserved.