Silanized metal electrode

Metal oxide electrodes have been coated with a monolayer of this same diaminosilane (Table 3, No. 5) by contacting the electrodes with a benzene solution of the silane at room temperature (30). Electroactive moieties attached to such silane-treated electrodes undergo electron-transfer reactions with the underlying metal oxide (31). Dye molecules attached to sdylated electrodes absorb light coincident with the absorption spectmm of the dye, which is a first step toward simple production of photoelectrochemical devices (32) (see Photovoltaic cells). 

Self-assembled monolayers (SAMs) provide a simple way to functionalize coinage metal electrode surfaces by organic molecules containing anchor groups such as thiols, disulfides, or silanes. The monolayers are usually well packed, ordered, and stable and can be easily tailored for certain applications by changing the functional terminal group in contact with the solution. Alkanethiol monolayers can... 

The chemical modification by silani2a-tion (or other chemical reactions) of carbon, oxide, or metal electrode surfaces [21, 22] or SAM formation on gold surfaces with thiol or disulfide compounds [23] has been utilized for the tip functionalization. The systematic chemical derivatization of the tips was carried out with silane [10, 24-27] or thiol [17, 18, 20, 28-37] derivatives. Today, chemical differentiation of the terminal groups by FFM [5-20,28, 36, 37] or adhesive force measurements [17, 18, 20, 24-28, 30-37] is called chemical force microscopy (CFM) [17]. Adhesive and frictional forces can be mapped in x-y planes as CFM images. The adhesive... 

Polysilicon. Polysihcon is used as the gate electrode material in MOS devices, as a conducting material for multilevel metallization, and as contact material for devices having shallow junctions. It is prepared by pyrolyzing silane, SiH, at 575—650°C in a low pressure reactor. The temperature of the process affects the properties of the final film. Higher process temperatures increase the deposition rate, but degrade the uniformity of the layer. Lower temperatures may improve the uniformity, but reduce the throughput to an impractical level. 

Ion Removal and Metal Oxide Electrodes. The ethylenediamine ( )-functional silane, shown in Table 3 (No. 5), has been studied extensively as a sdylating agent on siUca gel to preconcentrate polyvalent anions and cations from dilute aqueous solutions (26,27). Numerous other chelate-functional silanes have been immobilized on siUca gel, controUed-pore glass, and fiber glass for removal of metal ions from solution (28,29). 

In 1975, the fabrication of a chiral electrode by permanent attachment of amino acid residues to pendant groups on a graphite surface was reported At the same time, stimulated by the development of bonded phases on silica and aluminia surfaces the first example of derivatized metal surfaces for use as chemically modified electrodes was presented. A silanization technique was used for covalently binding redox species to hydroxy groups of SnOj or Pt surfaces. Before that time, some successful attemps to create electrode surfaces with deliberate chemical properties made use of specific adsorption techniques... 

The TFTs are made on transparent glass substrates, onto which gate electrodes are patterned. Typically, the gate electrode is made of chromium. This substrate is introduced in a PECVD reactor, in which silane and ammonia are used for plasma deposition of SiN as the gate material. After subsequent deposition of the a-Si H active layer and the heavily doped n-type a-Si H for the contacts, the devices are taken out of the reactor. Cr contacts are evaporated on top of the structure. The transistor channel is then defined by etching away the top metal and n-type a-Si H. Special care must be taken in that the etchant used for the n-type a-Si H also etches the intrinsic a-Si H. Finally the top passivation SiN, is deposited in a separate run. This passivation layer is needed to protect the TFT during additional processing steps. 

Mg Si bonds have long been inferred in reactions that generate hexaorganodisilanes from halo(triorgano)silanes and either a Grignard reagent or Mg metal ( Silico-Barbier reaction). Similarly, the electrochemical reduction of chloro(triorgano)silanes with sacrificial Mg electrodes yields... 

Covalent Attachments Based on Organosilanes. Organosilane reagents are known to form stable chemical bonds to the surfaces of metal oxide electrodes (20, In). Included in this category are silane attachments to thin platinum oxide layers on platinum which are formed when clean Pt surfaces are held at positive potentials (+1.0 V vs. SCE) in aqueous solution. The subsequent attachment chemistry is based on the known propensity of chloro- and alkoxy-silanes to undergo reactions in which Si-O-M bonds are formed by metathesis, e.g.,... 

SERS is used to study monolayers of materials adsorbed on metal substrates. Although the substrates are often used as electrodes, a wide variety of substrate formats have been found to exhibit SERS electrochemically modified electrodes [64], colloids, island films, particles grafted on silanized glasses [65-67], and more... 

Silanization is a widely used approach for activation of inorganic surfaces as glass and metals including gold electrodes of the PZ resonators. The deposited silane layer serves for further covalent attachment of biomolecules ... 

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