A STUDY OF H-2 TRAPPING IN YBA2CU2O7-DELTA LAALO3 (100) SAMPLES UNDER2H+ IRRADIATION/

A c-axis oriented YBa2Cu3O7-delta film, 180-230 nm thick, deposited on to (100) LaAlO3 by dc sputtering was irradiated at room temperature wi th 50 keV H-2+ (deuterium) ions to a dose of 1 x 10(16) cm-2. Secondar y-ion-mass spectroscopy analysis shows that after implantation the imp lanted H-2 is trapped in both the film and the substrate. For example, when the thickness of the YBCO film is equal to approximately 180 nm, it contains about 4.5% of the retained dose. The as-implanted H-2 dis tribution is essentially Gaussian-like and the depth (R(p)) of maximum H-2 concentration is approximately 485 nm. It is obvious that the tar get crystallinity has to be taken into account for the range data, sin ce the experiment values (R(p),R(p), and DELTAR(p)) are obviously larg er than the corresponding values from the transport of ions in matter code. This implantation makes the YBa2Cu3O7-delta film more granular. Within the irradiated LaAlO3 substrate, a damaged band was observed by cross-sectional transmission electron microscopy, which was centered at about 85% of R(p)(exp).