Showing papers on "Indium tin oxide published in 1989"

Effect of target‐substrate distance on the growth and properties of rf‐sputtered indium tin oxide films

Abstract: Indium tin oxide films have been deposited by rf sputtering an oxide target (90% In2O3+10% SnO2). Transparent conducting films have been obtained on room‐temperature substrates without any post‐deposition annealing. The effects of target‐substrate separation on the growth characteristics and film properties have been studied. The virtual‐source formation of the sputtered neutrals in the gap between the target and substrate has been observed. The effect of sputtering parameters on the position of the virtual source has been studied. It has been observed that the films deposited onto substrates kept below and above the virtual source have different properties. The films on substrates kept above the virtual source have (222) preferred orientations, with a direct optical band gap of 3.7 eV, an electron effective mass of 0.51 m, and a figure of merit ∼14×10−3 Ω−1. The films on substrates below the virtual source have preferred orientations along (440) and (400), with a band gap of 3.5 eV, an effective mass of ...

Electrochromic properties of conducting polyanilines

Abstract: A study has been made of the electrochromic behaviour of polyaniline films of potential use in passive display devices, and a preliminary examination of the properties of substituted polyanilines has also been carried out. Films of 'emeraldine-type' conducting polyanilines have been grown electrochemically from aqueous solutions onto glass substrates coated with gold or indium tin oxide. The authors have studied the electrochemistry of their redox reactions in acidic media to examine the kinetics and reversibility. Cyclic voltammetry was used to determine the electrode potentials for growth and redox switching and to obtain information on the electrode kinetics. The effect of electrode potential on the optical absorption spectra was observed, and was found to be consistent with polaron and bipolaron formation. The electrochromic colour contrast and switching times were measured as a function of pH; the requirements were somewhat conflicting, but a satisfactory compromise could be obtained around pH=0. By switching the electrodes over a constant potential step but from a variety of starting potentials, the influence on switching times of the initial oxidation state, and hence of the film conductivity, was investigated. Under suitable circumstances electronic conductivity, ionic transport or interfacial charge-transfer can limit the switching speed, but response times (for 50% transmission change) as short as 15 ms have been obtained without full optimisation. Of the numerous substituted polyanilines tried, only simple alkyl and alkoxy derivatives formed good polymeric films, and only the 2-ethoxy and 2-methoxy polymers gave good electrochromic behaviour. Switching times for these two were very fast, being less than 2.5 ms for both oxidising and reducing potential changes.

Light transmitting flexible film electrical heater panels

Abstract: Flexible heater panels comprising a light transmitting film substrate and a transparent conductive layer vacuum deposited on the substrate formed of (1) a light transmitting flexible plastic film substrate and (2) a vacuum deposited transparent conductive layer on a surface of the substrate selected from the group consisting of (i) a single lamina of tin oxide or indium tin oxide, (ii) a first lamina of indium oxide on the surface of the substrate and a second lamina of indium tin oxide over the first lamina, or (iii) a first lamina of tin oxide, indium oxide or indium tin oxide on the surface of the substrate, a second lamina of silver, platinum or palladium or alloys thereof over the first lamina, and a third lamina of tin oxide, indium oxide or indium tin oxide over the second lamina.

Electrical and optical properties of reactively evaporated indium tin oxide (ITO) films-dependence on substrate temperature and tin concentration

Abstract: The dependence of the electrical and optical properties of reactively evaporated indium tin oxide films on substrate temperature and tin concentration has been studied. Films of resistivity as low as 3*10-4 Omega cm and high visible transparency of about 91% have been obtained at higher deposition temperatures ( approximately 300 degrees C) for tin concentrations of 10-15 wt.% in the source alloy. Hall mobility in the films has been found to decrease with the addition of tin and increase with deposition temperature. An observed increase in carrier density with substrate temperature has been viewed as being due to the possibility that higher deposition temperature favours the incorporation of tin as Sn4+ in the films. In the optical band-gap calculation the effect of collision broadening, which is typical for a degenerate semiconductor, has been included and found to be significant.

In situ investigation of the optoelectronic properties of transparent conducting oxide/amorphous silicon interfaces

Abstract: Transparent conducting oxide (TCO)/hydrogenated amorphous silicon (a‐Si:H) interfaces are investigated combining kinetic ellipsometry and Kelvin probe measurements. It is shown that the correlation between both in situ techniques allows a detailed description of the optoelectronic behavior of these interfaces. The Schottky barrier at the TCO/a/Si:H interfaces, as revealed by Kelvin probe measurements, is correlated with the chemical reduction of the TCO surface during the early stage of a:Si:H growth, as evidenced by kinetic ellipsometry. In particular, indium tin oxide (ITO) and SnO2 are found to be reduced by the silane plasma at 250 °C. On the countrary, ZnO is found highly resistant upon plasma reduction. The influence of the substrate temperature during a‐Si:H deposition is analyzed. Finally, the technical consequences of this study are outlined.

Tin whisker-free tin or tin alloy plated article and coating technique thereof

Abstract: A tin or tin alloy plated article, particularly a film carrier which is protected against the generation of tin whiskers characterized in having an indium plated layer on the substrate thereof and a tin or tin alloy plated layer on said indium plated layer. There are also disclosed a coating process therefor as well as a novel and unique electroless indium plating bath therefor, said indium plating bath is an acidic, electroless plating bath characterized by including an indium salt and thiourea or a derivative thereof.

Organic-on-inorganic semiconductor photodetector

Abstract: High-efficiency high-bandwidth organic-on-inorganic (OI) semiconductor heterojunction photodetectors are discussed. The devices consist of a thin layer of the organic semiconductor perylenetetracarboxylic dianhydride (PTCDA) in contact with an inorganic semiconductor (Si) substrate. Indium tin oxide (ITO) is used as a transparent ohmic contact to the organic film. The external quantum efficiency of the detector was 85%, giving an internal quantum efficiency approaching 100%. The response time to fast optical pulses was 5 ns. Response times of OI detectors can be further reduced to about 100 ps by optimization of device parameters. >

Nuclear reaction analysis of hydrogen in optically active coatings on glass

Abstract: Films of WO3, Ta2O5, SiO2 and indium tin oxide as well as combinations of such films were analyzed for hydrogen with the 15N technique. Such coatings are used in optical devices for controlling reflectance and transmittance. H content and its changes during storage and in coloration experiments are reported. Effects of ion irradiation are described.

Process for producing a transparent layer with low resistivity

Abstract: A method for depositing on glass, by reactive cathode sputtering, a layer of indium tin oxide with low resistivity and high transparency, where a layer with at least a minimum intrinsic absorption coefficient is deposited and then a heat treatment, including of one reducing phase, is performed.

Method for manufacturing a liquid crystal display device with thin-film-transistors

Abstract: There is disclosed a liquid crystal color display of the active matrix type. A method of fabricating the display is initiated by depositing a transparent conductive material of indium tin oxide (ITO) as a thin layer onto a glass plate. Then chromium is deposited as an opaque film onto the ITO layer. The two layers are selectively removed, using a first mask pattern. A layer of an insulator consisting of Si 3 N 4 is deposited on the laminate within a reducing atmosphere of plasma. An I-type amorphous silicon layer is formed on the insulator layer. A highly doped N-type amorphous silicon layer is then formed. The N-type silicon layer, the I-type silicon layer, and the silicon nitride layer are selectively removed. An aluminum layer is formed on the laminate and then selectively etched away. Finally, the chromium layer is selectively etched away to form gates, gate leads, pixel electrodes, sources, drains and drain leads.

Transparent conducting indium doped ZnO films by dc reactive S-gun magnetron sputtering

Abstract: Transparent conducting ZnO films have been prepared by modified S-gun reactive dc magnetron sputtering using an indium doped Zn target. Films with a resistivity of 1.08 × 10−3 Ω cm and average transmittance of over 80% in the visible region were obtained. The influence of indium content at the surface of Zn target on the resistivity and transmittance of ZnO films was investigated. Optical properties of ZnO films in the 0.2–2.5-μm range were modeled by the Drude theory of free electrons. The reflectance of ZnO films in the 2.5–26.0-μm region was calculated.

Effects of Annealing Temperature on Microstructure and Electrical and Optical Properties of Radio-Frequency-Sputtered Tin-Doped Indium Oxide Films

Abstract: Indium tin oxide (ITO) films (0.3 μm thick), with a doping level of 28 mol% SnO2, were prepared by a radio frequency magnetron sputtering mehthod. The effects of postannealing on the microstructure and the electrical properties of the ITO films were investigated. The as-sputtered film showed an amorphous structure, whereas the films annealed at 350° and 510°C exhibited crystalline structures with grain sizes of 0.12 and 0.14 μm, respectively. Examination by TEM showed that the postannealing treatment induced SnO2 precipitates along the grain boundaries. The resistivity increased with increasing postannealing temperatures. The mobility of carriers appears to be responsible for the resistivity increase in these specimens. The mobility change is discussed in connection with the SnO2 precipitates.

Sputtering target for producing electroconductive transparent films and process for manufacture thereof

Abstract: A sputter target for producing electroconductive transparent films, which comprises indium oxide and tin oxide and having a shape such that not less than 80% by weight of the target is present in an erosion area on sputtering, and a process for manufacturing the sputtering target which comprises molding a slurry or a powder mixture containing indium oxide and tin oxide into a molded shape and sintering the molded shape are disclosed.

Blue Electroluminescence of Thin-Film Diamond Made by the Hot-Filament Method

Abstract: Blue electroluminescence has been observed in thin-film diamond deposited on a substrate when a mixture of methane and hydrogen gases react under heat treatment by tungsten filament. The diamond active layer is sandwiched between metal oxide insulating layers (HfO2 and Al2O3) which are formed by evaporation of metal oxides in oxygen plasma. Indium tin oxide film is used as a transparent electrode. The electroluminescence spectrum shows the peak at 435 nm and luminance is 3.6 cd/m2 at an applied voltage of 400 V.

Determination of catecholamines by an electrochemical flow-through detector with indium-tin oxide microelectrode arrays coated with Nafion.

Abstract: An electrochemical flow-through detector with indium–tin oxide interdigitated microelectrode arrays was used for the determination of catecholamines. This detector showed amplification of the current signals by redox cycling. The undesired response due to ascorbic acid can be eliminated by coating the electrode surface with Nafion.

New double-heterostructure indium-tin oxide/InGaAsP/AlGaAs surface light-emitting diodes at 650-nm range

Abstract: New double‐heterostructure indium‐tin oxide/InGaAsP/AlGaAs surface light‐emitting diodes have been fabricated by liquid‐phase epitaxy and rf sputtering methods. In this structure, indium‐tin oxide acts as both an n‐type cladding layer and a transparent conductor. Peak wavelength and full width at half maximum of the surface emitting spectrum were 653 and 17 nm, respectively. An output power of 1 mW was achieved at a current level of 66 mA, corresponding to a current density of 22 A/cm2 under pulsed operation for the diode with a 400 μm×450 μm emitting area. The optical emission was distributed over the entire emitting area.

Electrochromic display element

Abstract: PURPOSE:To simplify the production process of a display element by using a thermally decomposed carbon film for graphite to serve as a working electrode and using quartz glass which is the grown substrate thereof as a window material of the element CONSTITUTION:A transparent electrode 2 is formed on the glass window material 1 which is the quartz glass Dimethyl sulfoxide is used for an org solvent used for an ion conductive layer 3 and an indium tin oxide is used for the transparent electrode 2 On the other hand, the highly orientable thermally decomposed carbon film synthesized by controlling reaction conditions in a thermal cracking and chemical deposition method of benzene at 1,000 degC on a transparent quartz glass plate is used for the working electrode 5 The quartz glass plate from one face of which the carbon film is chipped away is used as it is as the window material 6 The display element which is stable, exhibits the display function of a high response speed and is suitable for industrial production is thereby obtd

Reactive ion etching of indium-tin-oxide films

Abstract: Oxygen deficient indium-tin-oxide (ITO) films exhibit a high electrical conductivity combined with high transmission in the visible spectral region. This combination of properties has led to its many electo-optic applications, mainly as transparent electrode in various devices. To take full advantage of ITO films in current and future devices, fine-line patterning methods must be developed for this material. The wet etch techniques that are commonly used in etching of ITO are not satisfactory. Reactive ion etching (RIE) combines the advantages of sputter etching, which is highly anisotropic but not selective, with those of plasma etching, which is selective but not anisotropic. The combined process (RIE) is both selective and highly anisotropic. This paper describes a RIE process for ITO using HI gas as an etchant.

Method of fabricating a sintered body of indium tin oxide

Abstract: A sintered body of indium tin oxide is fabricated by forming a finely divided mixture of indium oxide, tin oxide, aluminum oxide and silicon dioxide, compacting the mixture, and heating the mixture to a sintering temperature.

Chemical vapor deposition of silicon dioxide barrier layers for conductivity enhancement of tin oxide films

Abstract: Silicon dioxide for use as a diffusion barrier between soda lime glass and fluorine-doped tin oxide is deposited uniformly by atmospheric chemical vapor deposition from silane. oxygen, and nitrogen using a simple single-slot injector head. With a sufficiently thick silicon dioxide layer, the conductivity of the tin oxide is greatly improved by reducing the diffusion of sodium into the tin oxide as it is deposited between about 500 to 600 °C. Based upon the conductivity of thin lightly doped tin oxide films, it appears that at least 250 nm of silicon dioxide deposited on soda lime glass are required to essentially eliminate the diffusion of sodium into the tin oxide. However, only about 10 nm of silicon dioxide are required to obtain almost the full benefit of 250 nm thick films for moderately doped tin oxide films approximately 500 nm thick, The silicon dioxide deposition process is examined between 350 and 580 °C. The activation energy for the deposition is about 27 kJ/mole. Peak and average film deposition rates greater than 50 nm/sec and 10 nm/sec, respectively, may be obtained. The dependence of the film growth rate on the silane, oxygen, and propylene (an inhibitor) concentration is examined. The deposition rate is found to be limited by the rate of gas-phase reactions. Deposition conditions which yield high silane utilization and good film uniformity are discussed. The origin of undesirable by-product powder is studied. At low silane concentration, powder is mainly formed as the gases cool due to condensation from intermediate species.

Anti-electrostatic panel

Abstract: Undesirable electrostatic fields associated with dielectric surfaces of a solar panel cell array (60 , 60 ...) are reduced by a transparent conductive coating (70), which may be indium tin oxide, formed on the surface of the coverglass (62) of each individual solar cell of the array. In a preferred embodiment, conductive elastomer (74) is used to interconnect the transparent conductive coatings. The coatings may be connected to the spacecraft structure to prevent the fields from building up. This permits instruments sensitive to the fields to be used.