Abstract :
The influence of deposition temperature Ts. on the structure, transport property and magnetoresistance MR. behaviour
of pulsed-laser-deposited PLD.La–Ca–Mn–O films on Si substrates has been studied. An increase in resistivity and a
decrease in the peak resistivity temperature are found to occur simultaneously with increasing Ts. The largest MR value, with
a 40% Drrro.change in resistivity at 4.2 K, appeared in films deposited at 9008C, whilst the largest MR of 20% Drrro.
near room temperature was exhibited in films deposited at 5008C. The stoichiometry of the films was also examined. Both
calcium and oxygen deficiencies are found in the films deposited at higher temperature, which can be used to explain the
observed magnetoresistance results. q1999 Elsevier Science B.V. All rights reserved
