A CVD process for the preparation of transparent conducting layers of antimony-doped tin oxide has been developed utilizing dibutyl tin diacetate, antimony pentachloride, O2, H20, and N~ as carrier gas at a substrate temperature of 400~176It was designed to fulfill a need for more highly conducting coatings than those obtainable without doping, in the sheet resistance range 50-100 ohm/square, but still possessing an optical transmission in excess of 80% throughout the visible spectrum. Coatings to this specification are used extensively for a variety of electro-optic devices. A set of optimized deposition conditions is presented together with important optical, electrical, structural, and chemical properties of the films. Typical SnO2: Sb films have film thicknesses ranging from 1500-3600A with a sheet resistance of 50-150 ohm/ square, a specific resistivity of 0.0015-0.0032 ohm-cm, an n-type carrier concentration of 1.2 • 1020 cm -3, and a Hall mobility of 23 cm2/V-sec. They exhibit a light transmission of 85-91% net, and have an optimum dopant concentration within the range of 0.6-2.7 atomic per cent of antimony. The films are free of volatile chlorine, are chemically inert, and may be heated in air for prolonged periods without noticeable deterioration. Samples on sapphire substrates were heated in air to 1000~ for several hours without change in the sheet resistance.Transparent, electrically conducting thin films are required in many modern opto-electronic devices. Numerous materials, prepared by a variety of physical and chemical techniques (1,2), have been reported but in practice only two materials, tin oxide doped with antimony and indium oxide doped with tin, are widely used. Antimony-doped tin oxide coatings are conventionally prepared by spray hydrolysis of tin tetrachloride-antimony chloride mixtures (1-16), but for the high quality coatings required in electronic devices more sophisticated deposition techniques are needed. Sputtering techniques (1, 2, 17-20) have been used with better success. Chemical vapor deposition (21-22) could offer economic advantages of lower equipment cost and simpler processing.A chemical vapor deposition process for the preparation of transparent conducting coatings of nonstoichiometric tin oxide has been described in a previous paper (22). The subject of the present investigation is an important modification of this basic process by which a controlled quantity of an antimony dopant, which greatly increases the conductivity of the film, is introduced into the tin oxide. A full description of the apparatus and the proposed advantages of the CVD technique over spray hydrolysis were presented in the previous paper (22). Also given were extensive literature references on undoped tin oxide films; references in the present paper are therefore confined essentially to antimony-doped tin oxide films.In addition to lower conductivity, a second disadvantage of the undoped tin oxide is that it is nonstoichiometric and is therefore only a metastable phase. If it is subjected to any hig...

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The reactions of volatile tin organometallic compounds with oxygen have been investigated as a method for preparing transparent, electrically conducting layers of tin oxide. Several organometallic tin compounds were examined before the process was systematically optimized using dibutyl tin diacetate with excess O2 and H2O as reactants and N2 as carrier gas at a substrate temperature of 420°C in 10–20 min of deposition. The presence of water vapor during oxidation is beneficial.Important optical, electrical, structural, and chemical properties of the films have been examined. Typical SnO2 coatings are 800–5000Å thick, transmit 90–95% of visible light, have sheet resistances of 500–1700 ohms/square, resistivities of 0.005–0.09 ohm‐cm, a carrier concentration of 9×1018 cm−3 , and a Hall mobility of 10 cm2/V sec. Films of 0.4–0.5 μm consist of a mixture of polycrystalline tetragonal stannic oxide as evidenced by x‐ray diffraction, and of amorphous tin oxide phases as concluded from infrared spectroscopy. Electron diffraction analysis has indicated that the surface layers to a depth of 50Å are amorphous.

Thin films of cerium-activated alkaline earth thiogallate were investigated for the fabrication of blue-emitting thinfilm electroluminescent (TFEL) devices. The films were prepared by RF sputtering from targets with composition: MI_~Ga2S4:Ce=, where M = Ba, Ca, St, and 0.01 -< x -< 0.1. Photoluminescent (PL) emission spectra showed matching peak wavelengths to those obtained from electroluminescent (EL) emission for each alkaline earth thiogallate film. The optimum cerium concentration for EL emission intensity for strontium and calcium thiogallate films was determined to be x = 0.04 and 0.06, respectively. The EL brightness measured for the calcium thiogallate devices was almost twice that measured for the strontium thiogallate devices. This brightness variation, however, is due mainly to the difference in the lumen equivalent of the emission intensity. The cerium concentration dependence of the PL emission spectra of the thiogallate films is substantially decreased compared with the respective powder material suggesting inhomogeneous cerium incorporation in the films. ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 128.171.57.189 Downloaded on 2015-06-14 to IP