PREPARATION AND CHARACTERIZATION OF EPITAXIAL LA0.5SR0.5COO3 FILMS ON(001)LAALO3 BY PULSED-LASER DEPOSITION

Thin films of La0.5Sr0.5CoO3 were prepared in situ by pulsed laser dep osition on (100)LaAlO3 substrates. X-ray diffraction in Bragg-Brentano and four-circle geometry confirmed that full epitaxial films can be g rown in a wide deposition temperature range, from 500 to 730 degrees C , compared with that reported previously. Resistivity versus temperatu re measurements revealed that the films grown at temperature lower tha n 650 degrees C were metallic. However, those fabricated at higher dep osition temperatures showed a semiconducting behavior, similar to oxyg en-deficient ones grown at the lower temperatures.