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Anodic alumina film

Thin layers Anodic alumina films on aluminum 4.211... [Pg.229]

If the rf source is applied to the analysis of conducting bulk samples its figures of merit are very similar to those of the dc source [4.208]. This is also shown by comparative depth-profile analyses of commercial coatings an steel [4.209, 4.210]. The capability of the rf source is, however, unsurpassed in the analysis of poorly or nonconducting materials, e.g. anodic alumina films [4.211], chemical vapor deposition (CVD)-coated tool steels [4.212], composite materials such as ceramic coated steel [4.213], coated glass surfaces [4.214], and polymer coatings [4.209, 4.215, 4.216]. These coatings are used for automotive body parts and consist of a number of distinct polymer layers on a metallic substrate. The total thickness of the paint layers is typically more than 100 pm. An example of a quantitative depth profile on prepainted metal-coated steel is shown as in Fig. 4.39. [Pg.230]

The compact, nonporous anodic alumina film is the most suitable for fundamental investigations. It is grown by anodization, mostly under constant-current (galvanostatic) conditions, in neutral solutions of borates, tartrates, citrates, and phosphates, all of which possess significant buffering capacity and hence do not allow significant dissolution of the oxide. [Pg.423]

The growth of an anodic alumina film, at a constant current, is characterized by a virtually linear increase of the electrode potential with time, exemplified by Fig. 10, with a more or less notable curvature (or an intercept of the extrapolated straight line) at the beginning of anodization.73 This reflects the constant rate of increase of the film thickness. Indeed, a linear relationship was found experimentally between the potential and the inverse capacitance78 (the latter reflecting the thickness in a model of a parallel-plate capacitor under the assumption of a constant dielectric permittivity). This is foreseen by applying Eq. (38) to Eq. (35). It is a consequence of the need for a constant electric field on the film in order to transport constant ionic current, as required by Eqs. (39)-(43). [Pg.424]

Transient and Aging Phenomena in Anodic Alumina Films... [Pg.482]

VI. TRENDS IN APPLICATION OF ANODIC ALUMINA FILMS IN TECHNOLOGY... [Pg.487]

The past decade has been very fruitful for applications of anodic alumina films in the electronics industry. These applications... [Pg.487]

There are also several proposals to use anodic aluminum oxides in producing optoelectronic devices. Porous oxides may find use as antireflecting coatings for optical pathways. Anodic alumina films doped by Eu and Tb are promising for application in electroluminescent cells for TEELs.28... [Pg.492]

Matsui, K., Kyotani, T., and Tomita, A. Hydrothermal synthesis of single crystal Ni(OH)2 nanorods in a carbon-coated anodic alumina film. Adv. Mater. 14, 2002 1216-1218. [Pg.113]

Figure 2. Photovoltage transients for nanostructured silicon built-in the anodic alumina film (70 nm) at different temperatures. The shape of the laser pulse is presented for comparison. Figure 2. Photovoltage transients for nanostructured silicon built-in the anodic alumina film (70 nm) at different temperatures. The shape of the laser pulse is presented for comparison.
Figure 3. Dependence of the photovotage amplitude on the excitation intensity for 70 nm thick anodic alumina film with built-in silicon clusters. Figure 3. Dependence of the photovotage amplitude on the excitation intensity for 70 nm thick anodic alumina film with built-in silicon clusters.
Figure 4. Photovoltage transients in anodic alumina films of different thicknesses with built-in silicon clusters. The inset shows the thickness dependence of the photovoltag amplitude. Figure 4. Photovoltage transients in anodic alumina films of different thicknesses with built-in silicon clusters. The inset shows the thickness dependence of the photovoltag amplitude.
Figure 3. PL spectra measured from dichromatic luminescent image (a) blue area of porous anodic alumina film of 30 pm thickness after anodizing in oxalic acid electrolyte (b) red area of a porous anodic alumina film of 20 pm thickness after anodizing in orthophosphoric acid electrolyte, followed by immersion in europium nitrate and subsequent heat treatment at 200 °C for 30 min. Figure 3. PL spectra measured from dichromatic luminescent image (a) blue area of porous anodic alumina film of 30 pm thickness after anodizing in oxalic acid electrolyte (b) red area of a porous anodic alumina film of 20 pm thickness after anodizing in orthophosphoric acid electrolyte, followed by immersion in europium nitrate and subsequent heat treatment at 200 °C for 30 min.
A method for development of dichromatic luminescent images on the basis of porous anodic alumina film structure grown with the use of anodizing in several electrolytes and with selective europium deposition from alcoholic solution is proposed. [Pg.207]

DEFECTS IN POROUS ANODIC ALUMINA FILMS FORMED ON HIGH-PURITY ALUMINIUM... [Pg.491]

The formation of defects in porous anodic alumina films fabricated in phosphoric acid solutions has been studied. TEM and SEM examinations revealed that defects appear at the triple point junctions of the cell boundaries, where neighbouring celis meet. The defects represent voids in the anodic alumina and develop into spatial structures that comprise a central void at the triple-point junction extending into tubular branches that pass toward the pore wall. The defects are generated continuously during the anodic film growth under appropriate anodising conditions. Additional post-anodising treatment also results in periodic arrays of circular nanoholes in the pore walls. [Pg.491]

Figure 1. SEM images of the fracture sections of porous anodic alumina films formed in 1 vol.% phosphoric acid... Figure 1. SEM images of the fracture sections of porous anodic alumina films formed in 1 vol.% phosphoric acid...
Figure 2. (a) TEM images of an ultramicrotomed section of the anodic alumina films formed in 0.3 M phosphoric acid at 60 V (b) SEM images of anodic films fomied in 0.3 M phosphwic acid at 140 V and (c) in 1 vol% phosphoric acid at 178 V. Arrows in (a) show individual defeds. [Pg.493]

Figure 3. TEM images of ion beam-thinned porous anodic alumina films formed in phosphoric acid electrolyte (a) 0.3M acid at MOV (b) 1.2 M acid at a constant current of 5 mA/cm. ... Figure 3. TEM images of ion beam-thinned porous anodic alumina films formed in phosphoric acid electrolyte (a) 0.3M acid at MOV (b) 1.2 M acid at a constant current of 5 mA/cm. ...
A test structure for SPM cantilever tip shape deconvolution is described. The structure is based on aluminum with ordered tip-like surface. This structure is created by anodic oxidation of aluminum with subsequent selective etching of anodic alumina film. The developed structures consist of aluminum base with sharp tips of alumina. It is found that curvature radius of the tips are as small as 2 nm. Various types of tip shapes were charaterized by this structure. Experimental studies of the developed test structure containing an array of sharp tips may be used for three-dimensional imaging of the SPM tips. [Pg.531]

Porous anodic alumina films were formed by a two-step anodic oxidation of aluminum foil (99.99% purity) (thickness 100 jum) or of thin aluminum film sputtered onto silicon substrate. First step was performed under lOmA/cm constant current density in 40 g/1 aqueous solution of (COOH)2 during 60 min. After first anodization the formed anodic oxide was removed in the aqueous solution of 0.35 M H3PO4 and 0.2 M CrOs at 90°C. The second anodization was performed in the same regimes as the first one. The formed oxide was removed from the specimen after the first anodization. Nanostructured aluminum samples were rinsed in deionized water and dried in an argon flow. [Pg.532]

Anisotropic optical properties of free nanopotous anodic alumina films transparent in the visible spectrum for the restrided range of pore diameters and pore intervals are discussed. The basic experimental procedure is presented for the production of these films. Light scattered along pores was experimentally found to have partially a polarization perpendicular to the polarization of the incident light. The results obtained show that the nanoporous structure of anodic alumina films can be purposeful used in LCD to control a light propagation. [Pg.613]

The luminance enhancement was observed with the free-standing anodic alumina film by the naked eye because of anisotropic light scattering by spatially arranged nanometer-size pores. Fig. 1 demonstrates a high transparency of the free-standing anodic alumina film produced as compared to the reference Kimoto PF-90S M/M scattering film. [Pg.614]

Figure 1. The opaque scattering commercial Kiimto PF-90S M/M film (left) and the anodic alumina film (right). Figure 1. The opaque scattering commercial Kiimto PF-90S M/M film (left) and the anodic alumina film (right).
To get more detail on the light transfer by the anodic alumina oxide film, the light intensity enhancement from a flat white light emitting diode panel was examined. The porous anodic alumina film was placed between LEDs and a detector at a variable LED film distance and the light intensity Laa was... [Pg.615]

Figure 3. The ratio of light intensities with the porous anodic alumina film between the LED panel and the detector and without the film depending on the distance between the film and the LED... Figure 3. The ratio of light intensities with the porous anodic alumina film between the LED panel and the detector and without the film depending on the distance between the film and the LED...
The results obtained show that nanoporous structure of electrochemically anodized alumina films can be purposefully used to control light propagation, namely, to perform anisotropic light scattering in LCD backlight systems as well as potential modification of light polarization. [Pg.616]

Most recent applications of GD-AES are concerned with surface analysis — mainly depth profiling — of anodic alumina films [273], painted coatings [274], titanium carbide... [Pg.422]

N. Nourbakhsh, Anodic Alumina Films Preparation, Characterization and Investigation of Reaction and Transport Properties. Ph.D. Thesis, USC, May 1990. [Pg.564]


See other pages where Anodic alumina film is mentioned: [Pg.454]    [Pg.469]    [Pg.471]    [Pg.480]    [Pg.481]    [Pg.382]    [Pg.170]    [Pg.212]    [Pg.172]    [Pg.68]    [Pg.70]    [Pg.70]    [Pg.72]    [Pg.207]    [Pg.613]    [Pg.615]    [Pg.248]    [Pg.132]   
See also in sourсe #XX -- [ Pg.951 , Pg.953 ]




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