The goal of this study was to determine the scattering mechanisms and investigate the optoelectronic properties of indium molybdenum oxide (IMO) films. IMO films were deposited from an In2O3/MoO3 target with a weight ratio of 99/1, 95/5 and 90/10 via high-density plasma evaporation at room temperature. Based on the structural, electrical and optical properties, this study proposed that the neutral complex [(2Mo‧In)Oi″]x dominated at high doping content and high oxygen content, whereas ionized complex Mo‧‧‧In Oi″]‧ dominated at low doping level or low oxygen content. Uniform 99/1 IMO films with minimum resistivity of 3.56 × 10−4 Ω cm (corresponding to a mobility of 14.6 cm2V−1s−1 and carrier concentration of 14.3 × 1020 cm−3) and average visible transmittance of ∼85% were produced at an optimum oxygen content of ∼9%. Average optical transmittance exceeding 80% was demonstrated, and a structural change appeared at low oxygen contents.

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Indium molybdenum oxide (IMO) films were made from an oxidized target with In2O3 and MoO3 in a weight proportion of 99:1 by using a high density plasma evaporation with the substrate maintained at room temperature. Effects of the oxygen contents of 1%–28.6% on the structural and optoelectronic properties of the IMO films have been investigated. Results revealed that the addition of oxygen showed an increase in the mobility of the IMO films. Optimized oxygen vacancies and high mobility could dominant the conducting mechanism. X-ray photoelectron spectroscopy and x-ray diffraction analyses indicated that enhanced crystalline structure improved the mobility and transmittance of the film. Uniform IMO films with resistivity of 3.56×10−4 Ω cm and average transmittance of 85.06% over the wavelength of 450–800 nm were obtained.

The crystallization mechanisms for potentially high mobility molybdenum-indiumoxide (IMO) film were studied. The crystalline IMO films were deposited on unheated glass substrates via high-density plasma evaporation, and subsequent vacuum annealing was performed at 150, 200, and 250°C for 30 min. The results of x-ray diffraction and x-ray photoelectron spectroscopy and electrical properties suggested that the room-temperature crystallization was induced from the highest compressive strain, caused by the charged (Mo In ••• OЉ i ) • clusters and oxygen vacancies. The highest mobility of 75.8 cm 2 /Vs obtained at 250°C was due to the charged In-Mo +6 -O clusters and strain relaxation with (222)/(440) orientation change.

Thin films of thulium-activated ZnS have been deposited on glass, sapphire, and dielectric-coated silicon by thermal evaporation, RF magnetron sputtering, and low pressure chemical vapor deposition. Films have been annealed under different atmospheres (vacuum, N2, and H2S) and a range of temperatures (450-800~ to determine the effect on the emission properties. Photoluminescence measurements show that ZnS:Tm, halide films emit almost exclusively in the nearinfrared (800 nm), whereas sputtered ZnS:Tm,Li films are intense blue (478 nm) emitters after annealing in H2S at 800~Rare-earth activated ZnS phosphors have attracted attention as suitable candidates for full color ac thin film electroluminescent (ac TFEL) displays (1, 2). In particular, ZnS:Tm is a blue emitting material which has potential use as the blue component of color thin-film electroluminescent (EL) display panels. Very high efficiency blue cathodoluminescence was reported for ZnS:Tm powder material by Schrader et al. (3). However, thulium-activated ZnS thin films have so far not achieved the expected blue brightness in ac electroluminescent devices prepared by electron beam evaporation (4) or metal-organic chemical vapor deposition (5). The ZnS:TmF3 devices reported by Kobayashi et al. (4) emitted about an order of magnitude more photons in the infrared compared to the blue.The efficiency of thin-film phosphors depends strongly on the grain size and crystallinity of the films. Deposition method and processing parameters, especially postdeposition anneal conditions, control the grain structure and crystal orientation of polycrystalline phosphor films. In this study, thin films of nominal composition ZnS:TmF3, ZnS:TmOF, ZnS:TmC13, ZnS:Tm,Li, and ZnS:Tm,Na have been deposited on substrates such as Corning 7059 glass, dielectric-coated silicon and sapphire by coevaporation and RF magnetron sputtering. In addition, ZnS:Tm,C1 films have been grown by a low pressure chemical vapor deposition technique (LPCVD) similar in design to that used to prepare ZnS:Mn films (6).The optical absorption and emission properties of polycrystalline thulium-activated zinc sulfide were first studied in detail by Ibuki and Langer (7,8). Later investigations (9-11) focused on the symmetry of the substitutional site and the effect of different charge compensators on the luminescence of polycrystalline and single-crystal ZnS:Tm. Under UV excitation, five groups of emission lines are found in the visible to near-infrared region for ZnS:Tm at room temperature. The qualitative energy level scheme and emission lines are found in Fig. 1. There is a blue manifold near 478 nm (1G4 ---> 3H6), red lines at 650 nm (1G4 ---> 3F4) and 704 nm (3F3 ~ 3H6), and near-infrared manifolds at 785 nm (1G4 ~ 3H5) and 802 nm (3H4 ~ 3H6). Larach (12) reported that charge compensation of ZnS:Tm by alkali metal ions resulted in enhanced emission of the Tm 3' in the visible region compared with the infrared.The purpose of this work was to determine the effect of deposition technique and charge compensati...

The effect of oxygen backfilling on WO3 electrochromic thin films has been studied. Previously it was shown that O2 backfilling reduced the corrosion rate in H2SO4. In this phase of the study it has been shown that O2 backfilling also affects the EC response. For example, the coloration speed and optical efficiency were decreased while bleaching speed and self-erasure rate were increased. The current injection during coloration was found to be controlled by the same mechanism as the films without backfilling (i.e., WO3 resistivity and Helmholtz double layer). However, the magnitude of the current passed was lowered due to increased film resistivity from backfilling. The optical absorption maximum remained unchanged while the thermal hopping energy increased with oxygen backfilling. These observations suggest that a decreased density of optically active absorption centers resulted in the lower optical efficiency.