Chemical Characterization of DC-Sputtered In₂O₃ Films with a Top SnO₂ Layer

Abstract

In2O3thin films with a top layer of SnO2were deposited onto glass substrates by DC reactive-magnetron sputtering. After deposition, In2O3/SnO2samples were annealed in vacuum at 400oC. Structural, optical, and chemical composition was investigated by X-ray diffraction, UV-Vis spectroscopy and XPS, respectively. X-ray data showed that films grow polycrystalline, where indium oxide crystallized in cubic as the main phase, with a preferential growth at the [0002] direction and lattice parameter of 10.11 Å. Signals of rhombohedral phase were also detected. XPS depth profiles show that tin coexists inSn2+andSn4+, while indium maintains the In2O3stoichiometry. Binding energy of Sn4+bound to oxygen was detected at 468 eV while In2+bound to oxygen at 444.7 eV. Nor tertiary compounds were detected at the In2O3/SnO2interface, neither In or Sn in metallic state.

Single-crystalline-like indium tin oxide thin films prepared by plasma enhanced atomic layer deposition

“…In the literature, the Sn incorporated into In 2 O 3 films can bond with oxygen in Sn 4+ and Sn 2+ states, which are widely checked using XPS. [30][31][32][33][34] The XPS Sn 3d spectra of the films are investigated as shown in Fig. 3c.…”

Ultrathin tunable conducting oxide films for near-IR applications: an introduction to spectroscopy shape theory

“…Samples 1 and 3 have a highly preferred orientation in (002) lattice plane, while that of sample 2 has a major orientation in (110) lattice plane, both orientations have a higher crystalline quality. The most intense (002) reflection indicates growth to the c-axis [0002] at perpendicular direction to substrate that yields a tensile biaxal microstrain, the related peaks at 34.38 • , and 56.46 • correspondings to the (002) and (110) lattice planes in samples 1 and 3 [7,22,23]. On the other hand, the (110) orientation plane in the sample 2 has compressive biaxial microstrain, the related peaks at 31.66 • , 34.38 • and 56.46 • correspondings to the (100), (002), and (110) lattice planes produced through a growth that is parallel to the substrate surface.…”

“…ADL [3,4], DC/RF sputtering [5][6][7][8], spray pyrolysis [9], sol-gel [10] among other techniques have been used for the manufacture of oxidized conductive materials. Principal challenges in the fabrication of AZO are its low thermal stability and problems of environmental degradation due to the high reactivity of aluminum [5].…”