ELECTRICAL CHARACTERIZATION OF SEMICONDUCTING LA DOPED SRTIO3 THIN-FILMS PREPARED BY PULSED-LASER DEPOSITION

We present the growth of La doped SrTiO3 thin films on MgAl2O4 (100) s ubstrates using the Pulsed Laser Deposition (PLD) technique. The cryst al quality of the films was analyzed by X-Ray Diffraction (XRD) and Ru therford Backscattering Spectroscopy (RBS). A substitution of La on th e Sr sites can be deduced for several La concentrations from the RES m easurements in combination with Hall measurements. Temperature depende nt conductivity measurements using the van der Pauw technique reveal t he semiconducting behavior of the films. The conductivity of the sampl es at room temperature can vary over several orders of magnitude depen ding on the La concentration in the films and the oxygen partial press ure during PLD. The Hall mobility of the films was found to be tempera ture dependent and is about 3 cm(2)/Vs at room temperature, in contras t to bulk single crystals, where the mobility is known to be 6 cm(2)/V s. A scattering mechanism is proposed to explain the observed mobility behavior.