Effects of Substrate Temperature on Properties of Tin-Doped Indium Oxide Films Deposited by Activated Electron Beam Evaporation

摘要

The coating process was conducted using an inline-type plasma deposition system. Thin and thick films containing SnO_2 were prepared from the starting material sintered ITO pellets (0-15 wt% SnO_2). The thin film (<0.6 μm thick) showed an amorphous-like structure. The thick film (>1 μm thick) showed a well-ordered crystalline structure. The crystalline and electrical properties of the films were dependent on the deposition temperature and were closely related to the SnO_2 contents. Films deposited on substrates at temperatures of 50-180℃ com­prised a mixture of amorphous and polycrystalline phases and had a hazy appearance because of light scattering at the rough surface. That appearance was not observed in films with 0 wt% SnO_2 content, but it was observed with increasing SnO_2 content and substrate tempera­ture. In films with thickness greater than 0.6 μm, the hazy appearance was more pronounced than in films with thickness of less than 0.6 μ m. Polycrystalline ITO films with a clean and transparent appearance, as well as minimum resistivity of 1.7 × 10~(-4) Q cm, were obtained on substrates at 180℃ (4 wt%, 7.5 wt% SnO_2). Transparent and uniform ITO films with sheet resistance of 1.7 Ω/□ were obtained at 2.1 μm thickness at a high deposition rate (ca. 0.5 μm/min).