Effects of ambient gas pressure on (1-x)SrTiO3-xBaTiO(3) films prepared by pulsed laser deposition

Ambient gas pressure in pulsed laser deposition process has been observed to significantly modify the lattice parameters of (Sr1-xBax)TiO3 thin films. The lattice parameters a(0) of the films deposited under low ambient pressure regime (P less than or equal to 0.01 mbar) were larger than those found on the films grown under high ambient pressure regime (P greater than or equal to 0.1 mbar), regardless of the thin film composition (i.e., x value), substrate materials (Pt/Si or Si), or ambient gas species (O-2 or N-2). It is proposed from these observations that the large lattice parameters a(0) of the films grown under low-pressure environment result from higher concentration of vacancies, which, in turn, are induced by the bombardment of energetic species ejected by laser beams. (C) 1996 American Institute of Physics.