Epitaxial SnO2 thin films grown on (1̄012) sapphire by femtosecond pulsed laser deposition

Abstract

An ultrafast (100 fs) Ti sapphire laser (780 nm) was used for the deposition of SnO2 thin films. The laser-induced plasma generated from the SnO2 target was characterized by optical emission spectroscopy and electrostatic energy analysis. It was found that the ionic versus excited-neutral component ratio in the plasma plume depends strongly on the amount of background oxygen introduced to the deposition chamber. Epitaxial SnO2 films with high quality and a very smooth surface were deposited on the (1̄012) sapphire substrate fabricated at 700 °C with an oxygen background pressure of ∼0.1 mTorr. The films are single crystalline with the rutile structure, resulting from the high similarity in oxygen octahedral configurations between the sapphire (1̄012) surface and the SnO2 (101) surface. Hall effect measurements showed that the electron mobility of the SnO2 film is lower than that of bulk single crystal SnO2, which is caused by the scattering of conduction electrons at the film surface, substrate/film interface, and crystal defects.

Temperature-dependent orbital-moment anisotropy in dilute magnetic oxides

“…XRD pole figures ͑not shown here͒ indicate that the film is single crystalline and is epitaxially grown with its ͓010͔ axis along the ͓1210͔ direction of the Al 2 O 3 substrate, consistent with the previous report in Ref. 16. The dependence of the ͑101͒ plane spacing, d 101 , on the V concentration is shown in Fig.…”

Structure and magnetism of V-doped SnO2thin films: effect of the substrate

“…The XRD patterns indicate that both of the fi lms are of rutile structure; the fi lm grown on the Si substrate is polycrystalline with random orientation, while the fi lm grown on the Al 2 O 3 substrate has (101) orientation. Pole fi gure results (not shown) further revealed that the fi lm grown on Al 2 O 3 is single crystal and is epitaxially grown with its [010] axis along the [1¯210] direction of the Al 2 O 3 substrate, consistent with the result in [12]. The (101) plane spacing of the fi lms grown on Al 2 O 3 decreases almost linearly as the V concentration increases, suggesting that at least some V goes into the SnO 2 lattice and substitutes for Sn.…”

Growth and magnetic characterization of Co nanoparticles obtained by femtosecond pulsed laser deposition

“…[6][7][8][9][10][11][12][13][14][15] In spite of this effort, however, very little has been done on the nature and properties of the material obtained from this ablation process once it is deposited on a substrate surface, either in the form of a continuous film or as nanoparticles. Deposition of continuous thin films using fs lasers has been successful in the case of oxides or nitrides, [16][17][18][19][20][21] with ablation in the presence of a gas in the deposition chamber that reacts or interacts to some extent with the ejected material, leading to the growth of a continuous film on the substrate.…”