CONTROLLED MODIFICATION OF INTERFACIAL STRAIN AND TWINNING IN YBA2CU3O7-DELTA FILMS ON VICINAL SRTIO3(001)

The structure of twinning in YBa2Cu3O7-delta thin films grown on vicin al SrTiO3 (001) by pulsed laser deposition has been studied as a funct ion of the vicinal miscut angle by x-ray diffraction using the two-dim ensional q-scan technique with a four circle diffractometer. Our resul ts reveal a strong correlation between the miscut of a SrTiO3 (001) su bstrate and the strain occurring at the interface between substrate an d film. Depending on the proper choice of miscut orientation and angle , one of the two twin systems can be suppressed and approximate to 70% untwinned growth can be achieved. [S0163-1829(98)00406-8].