Cr/Au electrodes

The electrocoloration (high-field stress) experiments were performed on Fe-doped SrTiC>3 single crystals (0.22 mol % Fe). Circular microelectrodes (10 pm in diameter and 20 or 30 pm in distance) were again prepared by a lithographic lift-off process from an evaporated 20 nm Cr/200 nm Au film. Two further Cr/Au electrode stripes were used to achieve the resistance degradation (see Fig. 32a). At 493 K, an electrical... 

Impedance electrodes have also been investigated as detectors for microchip microdialysis applications. An on-chip microdialysis system with inline sensing electrodes for impedance detection was developed [41], Cr/Au electrodes were used to determine the electrical resistance of changes in the concentration of phosphate-buffered saline (PBS) solutions that were used to characterize the system. The system monitored concentration changes with a 210-s system response delay. The lag time was attributed to dead volume in the tubing between the syringe pumps and the microsystem. 

R setxoir flow channel Perfusion flow channel Cr/Au electrodes... 

Cr/Au-electrodes YBCO-eleotrodes calculated (equilibrium) caicuiated (quenched) 1 I I I CC 0.4 0.2 0 YBCO/Ag-electrodes I I I ... 

As metal electrodes, various combinations, such as Cr/Au, Ti/Au, Au only, Pt/Cr, and Pt/Ti, have been used. A thin 10-nm Au layer was sometimes used because it was transparent to the visible wavelength (abs 0.2-0.3) [133, 363]. 

In PDMS chips, metal electrodes cannot easily be made on PDMS because of its pliable nature. So the Au/Cr microband electrodes have first been formed on a glass plate, which was then aligned and sealed with a PDMS channel plate [748],... 

Why should not the glass chips that contain Au/Cr metal electrodes be thermally bonded [748,762] (2 marks)... 

The influence of anion adsorption on Zn U PD on Au(l 11) was further studied in the presence of halide ions [201]. The order of the adsorption strength of the anions on Zn UPD was found to be different from that of specific adsorption on a substrate Au electrode ClO4 < SO4 < PO4 < cr < Br < I . In phosphate solutions, chloride and bromide ions did not influence the Zn UPD, and iodide ions inhibited this process (see Fig. 5). 

Fig. 10.9 SNIFTIR spectra obtained in the 1700-700 regionfora2mM [Cr(DMSO)g] (0104)3 solution in dimethylacetamide at an Au electrode. The reference potential was 0.16 V against an internal ferrocene-ferrocinium couple spectra were recorded at more negative potentials at intervals of 100 mV (From reference 17, with permission.)...

Cr patterns are formed on the backside of the glass snbstrate in addition to surface Cr/Au patterns. Cr patterning on both sides enables to define the exposure areas. For finer patterns, exposure areas cannot be defined perfectly dne to the inflnence of UV diffraction at the edge of backside Cr patterns even if Cr shadow layers are formed on both sides of a glass substrate. For this reason the negative resist (CA3000) was formed to avoid formation of Ni walls between metal electrodes. Two additional techniqnes enabled the realization of the 3-D micromesh metal structnres formed on the planar electrodes on the glass surface. 

Polarograms and cyclic voltammograms for tris(bipy) complexes of Cr and Cr in DMF have been reported. On the basis of the half-wave potential shift caused by methyl substitution on the bipy ligands it was concluded that each excess electron of the reductant species of the redox systems Cr(bipy)3/Cr(bipy)3 Cr(bipy)3 /Cr(bipy)3 and Cr(bipy) /Cr(bipy)3 " occupies a ligand n orHtal. The electrochemical reduction of [CrPh2(bipy)2]I at Pt and Au electrodes in MeCN and Me2SO has been investigated. Two reversible one-electron reductions were observed, as in reaction... 

FIGURE 2.3.12 (a) Schematic diagram of experimental setup for scanning Kelvin probe microscopy (SKPM). (b) Profiles of an L = 5.5 J,m P3HT transistor with Cr electrodes taken at three different temperatures V = 0 V, = -8 V). The inset shows a profile obtained after switching the source and drain contacts on the same TFT with both Cr and Cr-Au contacts Vg = 0 V, = -8 V). (From Burgi, L. et ah, J. Appl. Phys., 94, 6129-6137, 2003. Reprinted with permission. Copyright 2003, American Institute of Physics.)... 

For bottom-contact TFTs, gate electrodes (Cr/Au), gate dielectric (SiN, /Si02 bilayer), and source and drain electrodes (Cr/Au) were defined by digital lithography... 

Fig. 14 Molecular structure and geometry of LB monolayer of 1 sandwiched between Au electrodes with direction of enhanced electron flow. The substrate was glass. 50 mmx50 mm j0.4mm, covered either by a Cr adhesion layer or by a hydrophobic xylene covering, followed by an evaporated Au film 50 mm x50 mm x 50 nm. then the LB monolayer or multilayer, then by 48 cylindrical Au pads. 17 nm thick and with an area of 0.283 mm. (From Ref. [34].)...

Mkrowave in Mkrofluidks, Fig. 5 Cross-sectional and top view of the coplanar waveguide heater presented in Ref. [4]. The ehannel is aligned with the coplanar waveguide so that the fluid interacts with the microwave power. The mimtfluidic chip is made of PDMS, and the electrodes of the coplanar waveguide are made of Cr/Au (Figure from Ref. [4], Reproduced by permission of lOP PubUshing, http //dx.doi.Org/10.1088/0960-1317/17/l 1/ 008)... 

A galvanic cell was formed with both n- and /7-type Si in alkaline solutions in the dark. A solution of 25 % tetramethylammonium hydroxide (TMAH) at 80 °C was used by Kelly and coworkers for galvanic cell formation with a Au/Cr electrode. Etching in aerated 2.0 M KOH(aq) at 70 °C led to surfaces that exhibited pyramidal protrusions. When a Pt or Au electrode was used to form a galvanic cell during etching, the formation of such large pyramids was suppressed. 

Underneath the Au electrode (removable with aqua regia) is a Cr/Cr203 layer. This can be removed by a drop of HCl on the surface and scratching the layer with A1 wire. 

Studies of capacitance-voltage characteristics were done on metal insulator semiconductor (MIS) structures. The MIS structure consists of PCBM spin-coated on top of DNA-CTMA. For the metal electrode in the MIS device Cr/Au was chosen as the bottom as well as top electrode. Similarly, MIM devices were also fabricated and studied. For the MIM devices characteristics of capacitance vs frequency show no significant change in capacitance throughout the measured frequency range (see Fig. 21). On the other hand, MIS devices show rise in capacitance between frequency ranges of 10 to 10 Hz, corresponding to the dielectric relaxation of the PCBM semiconductor. At lower frequencies, capacitance further increases to an... 

After a heat treatment of several hours the electrodes are deposited by sputtering a 50 nm base layer of Ni/Cr or NiAVi followed by 1.5 pm Au-layer generated by galvanization. 

In view of its inertness Pt is mostly used, but it should be borne in mind that in the presence of strongly reducing agents such as Cr(II), Ti(IH) and V(IV) Pt can catalyse the reduction of H+ ions and then does not satisfy the aim of electrode inertness. Under certain conditions one can use electrodes of Pd, Au, graphite, conducting glass or glassy carbon. 

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