Aluminum oxide thin films

Figure 4.S7. SEM images of an electroluminescent phosphor particle, ZnS (used in backhght displays for cell phones, watches, etc.), before (a) and after (b) the deposition of an aluminum oxide thin film. This film is a transparent coating that prevents the phosphor particle from undergoing humidity-accelerated decay. A technique known asfluidized-bed CVD was used, where a carrier gas both delivered the precursors to a vertically aligned CVD chamber, and dispersed the powdery sample in order to expose all surface regions to the precursor vapors.

Yu, G.T. and S.K. Yen, Determination of the diffusion coefficient of proton in CVD gamma aluminum oxide thin films. Surface and Coatings Technology, 166, 195 (2003). 

Aluminum oxide Thin film applications in field effect transistors, coatings for carbide tools. 

Z.W. Zhao, B.K. Tay, C.Q. Sun, V. Ligatchev, Oxygen lone-pair states near the valence band edge of aluminum oxide thin films. J. Appl. Phys. 95(8), 4147-4150 (2004)... 

Phani AR, Santucd S. Evaluation of structural and mechanical properties of aluminum oxide thin films deposited by a sol-gel process comparison of microwave to conventional anneal. Journal of Non-Crystalline Solids 2006 352 4093-100. 

Since aluminum does not form an ohmic contact with tin oxide, a double layer metallization was used. By depositing a thin layer (-50 nm thick) of Cr underneath the Al, a good ohmic contact to the tin oxide thin film was formed. 

H. Kim, C. M. Gilmore, J. S. Horwitz, A. Pique, H. Murata, G. P. Kushto, R. Schlaf, Z. H. Kafafi and D. B. Chrisey, Transparent conducting aluminum-doped zinc oxide thin films for organic light-emitting devices. Appl. Phys. Lett. 76 (2000) pp. 259-261. 

Liquid phase deposition (LPD) process is the formation of oxide thin films from an aqueous solution of a metal-fluoro complex which is slowly hydrolyzed by adding fluoride scavengers such as boric acid or aluminum metal [47], namely... 

Taguchi H., Matsu-ura S., Nagao M., Kido H. Electrical properties of perovskite-type La(Cri, Mn,)03+j. Physica B 1999 270 325-331 Tahar R.B.H., Ban T., Ohya Y., Takahashi Y. Optical, structural, and electrical properties of indium oxide thin films prepared by the sol-gel method. J. Appl. Phys. 1997 82 865-870 Tahar R.B.H., Ban T, Ohya Y., Takahashi Y. Electronic transport in tin-doped indium oxide thin films prepared by sol-gel technique. J. Appl. Phys. 1998 83 2139-2141 Tahar R.B.H., Tahar N.B.H. Mechanism of carrier transport in aluminum-doped zinc oxide. J. Appl. Phys. 2002 92 4498-4501... 

Finishes for aluminum products can be both decorative and useful. Processes in use include anodic oxidation, chemical conversion coating, electrochemical graining, electroplating (qv), thin film deposition, porcelain enameling, and painting. Some alloys respond better than others to such treatments. 

Aluminum, although highly electropositive, does not react with water under ordinary conditions because it is protected by a thin (2—3 nm) impervious oxide film that rapidly forms even at room temperature on nascent aluminum surfaces exposed to oxygen. If the protective film is overcome by amalgamation or scratching, water rapidly attacks to form hydrous aluminum oxide. Because of the tendency to amalgamate, aluminum and its alloys... 

Lee, I. and Wool, R.P., Controlling amine receptor group density on aluminum oxide surfaces by mixed silane self-assembly. J. Thin Solid Films, 379, 94 (2000). 

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. 

Khmenkov M, Nepijko S, Kuhlenbeck H, Baiimer M, Schldgl R, Ereund H-J. 1997. The structure of Pt-aggregates on a supported thin aluminum oxide film in comparison with unsupported alumina a transmission electron microscopy study. Surf Sci 391 27-36. 

Specific structural features are observed in the formation of composite oxides. Kobayashi, Shimizu, and their co-workers have, in a series of papers, reported studies of the structure of barrier alumina films, anodically formed on aluminum covered by a thin (5 nm) layer of thermal oxide.198,199 Their experiments have shown that the thermally oxidized thin layer generally contains y- alumina crystals of about 0.2 nm size. This layer does not have a pronounced effect on ionic transport in the oxide during anodization. Also, islands of y -alumina are formed around the middle of anodic barrier oxides. They are nucleated and developed from tiny crystals of y -Al203 and grow rapidly in the lateral direction under prolonged anodization.198,199... 

Figure 4.6. Cross-sectional SEM images of an A1PO film deposited on Si02 and cured at (a) 275 °C, and (b) flash annealed to 600 °C. [Reproduced with permission. Meyers, S. T. Anderson, J. T. Hong, D. Hung, C. M. Wager, J. F. Keszler, D. A. 2007. Solution processed aluminum oxide phosphate thin-film dielectrics. Chem. Mater. 19 4023-4029. Copyright 2007 American Chemical Society.]...

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