Grown-on oxide films

A number of oxides can be modeled by vacuum-grown thin oxide films and oxide nanoparticles which are amenable to atomic level characterization with the application of surface-sensitive (surface science) methods. This is crucial for the advancement of the field because in many cases oxide surfaces are not simple truncations of the bulk oxide structure. Defects such as oxygen vacancies, despite being minority surface species, play an important role in the catalytic properties of an oxide surface. In this chapter, we have presented results on the synthesis, characterization and catalytic properties of Ga Oj, In Oj, and V Oj, Nb Oj, Pd O and PdO vacuum-grown thin oxide films and oxide nanoparticles. The catalytic activity of the model systems can be examined at atmospheric pressure and compared to those... 

The absorption spectrum of an electrochemically grown nickel oxide film shows a peak in the vicinity of 0.5-0.6 pm. Therefore, depending on film thickness, nickel oxide is transparent or pale green in the bleached state and brown-bronze in the coloured state. 

In order to find out the region of reduced electron beam-induced damage, the investigations on the compulsive reduction of the silicon oxide film were performed by using thermally grown silicon oxide film as a reference sample. The electron beam-induced damage were evaluated as a function of LVV spectra intensity ratio for the elemental silicon and the silicon oxide. 

The relative sensitivity factor (RSF) of LW spectra of the silicon were obtained for the calculation of the thickness estimation of the ultra thin native oxide film. Although the characteristics nature of the thermal silicon oxide film on the silicon wafers might be different from that of the ultra thin native oxide film, RSF of LVV spectra for the silicon were obtained by the measurement of Auger signal intensity using thermally grown silicon oxide film of 100 nm thickness as a reference sample... 

The study on the electron beam-induced damage of the silicon oxide film was carried out using thermally grown silicon oxide film as a reference sample. Although the reduction of the oxide film is sensitive to the electron beam density, the long acquisition time reduce the electron beam-induced damage because of the heat dissipation in the thin oxide films. 

Shin C-S, Kim Y-W, Gall D, Greene JE, Petrov I (2002) Phase composition and microstructiffe of polycrystalline and epitaxial TaN layers grown on oxidized S/(001) and MgO(001) by reactive magnetnm sputter deposition. Thin Solid Films 402 172-182... 

To illustrate some of the different approaches, let us consider passive films grown on Fe-Cr alloys. It has been established since 1911 [72] that an increase of Cr in the alloy increases the stability of the oxide film against dissolution. 

Figure 5 Images of a thin region of an epitaxial film of Ge on Si grown by oxidation of Ge-implanted Si (a) conventional TEM phase contrast image with no compositional information and b) high-angle dark-field STEM image showing atomically sharp interface between Si and Ge. (Courtesy of S.J. Pennycook)...

Conventional electronic devices are made on silicon wafers. The fabrication of a silicon MISFET starts with the diffusion (or implantation) of the source and drain, followed by the growing of the insulating layer, usually thermally grown silicon oxide, and ends with the deposition of the metal electrodes. In TFTs, the semiconductor is not a bulk material, but a thin film, so that the device presents an inverted architecture. It is built on an appropriate substrate and the deposition of the semiconductor constitutes the last step of the process. TFT structures can be divided into two families (Fig. 14-12). In coplanar devices, all layers are on the same side of the semiconductor. Conversely, in staggered structures gate and source-drain stand on opposing sides of the semiconductor layer. 

Historically, the first capacitors using an electrocfiemical system were the electrolytic capacitors. Built like film capacitors, they have electrodes made of aluminum foil on which by electrochemical oxidation a thin film of aluminum oxide (i.e., 10 to lOOnm thick) is grown to serve as the dielectric. Solutions are used as the electrolyte which aid self-repair of the oxide film on aluminum after accidental damage. Such electrolytes are solutions of salts of a number of orgaiuc acids (trifluoroacetic, salicylic, and some others). Because of the small thickness of the oxide layer, electrolytic capacitors have a markedly higher capacity than film capacitors. They can thus be used in the microfarad range. 

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