Metal oxide semiconductor dependence

In a series of transition metal oxide semiconductor powders, photochemical activity in the decarboxylation of oxalic acid was controlled by surface properties and the presence of recombination centers, which in turn depended on the preparation method Similar effects have also been noted in the photodecarboxylation of pyruvic acid and formic acid... 

Electrodeposition of dissolved precursors (especially in aqueous solutions) is a low cost and scalable method which is well suited to the mass production of thin films of metal-oxide semiconductors such as Ti02, Cu20, WO3, and ZnO. Control of temperature, pH and the deposition potential are important because the corresponding electrochemical reactions within the deposition bath mainly depend on these parameters. 

Upon irradiation, redox dye photosensitizers adsorbed on the surface of wide-bandgap metal oxide semiconductors readily inject an electron in the conduction band of the solid. While charge injection has been found for numerous efficient systems to occur in the femtosecond time frame, the electron back transfer takes place much more slowly, typically in the microsecond-millisecond domain. This charge recombination process can be intercepted by reaction of a reducing mediator M with the oxidized dye (Eq. (43)). The overall efficiency of the light-induced charge separation then depends upon the kinetic competition between back electron transfer and dye regeneration processes. 

Metal oxide semiconductor field effect transistors (MOSFETs) constitute other materials with applicability in the development of biosensors. Usually, a MOSFET structure consists of a metal gate on top of an oxide layer, tyqjically Si02 [189]. The catalytic properties of these sensors depend upon the type of the gate metal as well as the temperature at which the MOSFET is operated. The most used catalytic metals used as gate materials are Pd (is a good... 

ZnO is being regarded as one of the important metal oxide semiconductors for future applications. Since its chemical and physical properties are highly dependent on composition and shape (defects), reliable methods are necessary to ensure control over the latter. The heterocubane (MeZnO Pr)4 was shown to be a suitable organometallic precursor for gas-phase CVS and solid-state synthesis of nanoscaled Interestingly, highly... 

Shen, C. Li, M. F. Yu, H. Y Wang, X. P Yeo, Y. C. Chan, D. S. H. Kwong, D. L. 2005. Physical model for frequency-dependent dynamic charge trapping in metal-oxide-semiconductor field effect transistors with HfOj gate dielectric. Applied Physics Letters, 86 093510(1-3). 

Organic semiconductors are used in many active devices. Many can be processed in solution and can therefore be printed. The charge transport properties largely depend on the deposition conditions, which are influenced by the nse of solvents, the deposition technique, concentration, interfaces and so on. Most of the organic semiconductors used today are p-type (e.g., pentacene and polythiophene), but the first n-type materials have also become available and these mean that complementary metal-oxide-semiconductor (CMOS) circuits can now be fabricated. 

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