Electrodes polyimide

Incorporation of AlCacac) into the polyimide disappointingly shows no significant reduction in volume resistivity relative to the polymer alone. Replicate measurements (1.59 x 10 and 1.12 x 10 ° ohm-cm) on two independently cast films support this conclusion. Reorientation of the same film in the electrode assembly yielded identical results suggesting uniform behavior throughout the film containing Al(acac),. Similar results were obtained on NiCl bl O filled polyimides. (Table V)... 

The polyimide-CNT composites have good biocompatibility and conductive properties, which can be used to fabricate the electrode arrays, and enhance their biocompatibility. For example, they can be used as the stimulator embedded in the blind eyes, and can be used for the electrode arrays transplanted in the human body without damaging human organs and tissues (Tulevski et al., 2007). 

Higuchi, E., Okamoto, K., Miyatake, K., Uchida, H., and Watanabe, M. Gas diffusion electrodes for polymer electrolyte fuel cell using sulfonated polyimide. Research on Chemical Intermediates 2006 32 533-542. 

Schematic of the Si-nMEA fabrication process (a) sputter Au layer on double-side polished wafer (b) pattern Au layer with liftoff process (c) spincoat and cure a polyimide layer (d) perform the double-sided photolithography to pattern etch pits (e) etch Si in ICP-DRIE to form Au/Si electrode (f) dice the wafer into a single die (g) RIE etch the polyimide layer with a shadow mask to expose current collecting region (h) electroplate Pt black on Au layer (i) sandwich both electrodes with Nafion 112 in a hot-press bonder. (Reprinted from J. Yeom et al. Sensors Actuators B107 (2005) 882-891. With permission from Elsevier.)...

Metal ion modified polyimide films have been prepared to obtain materials having mechanical, electrical, optical, adhesive, and surface chemical properties different from nonmodified polyimide films. For example, the tensile modulus of metal ion modified polyimide films was increased (both at room temperature and 200 0 whereas elongation was reduced compared with the nonmodif ied polyimide (i). Although certain polyimides are )cnown to be excellent adhesives 2) lap shear strength (between titanium adherends) at elevated temperature (275 0 was increased by incorporation of tris(acetylacetonato)aluminum(III) (2). Highly conductive, reflective polyimide films containing a palladium metal surface were prepared and characterized ( ). The thermal stability of these films was reduced about 200 C, but they were useful as novel metal-filled electrodes ( ). 

Thin-fihn transistors have been fabricated by depositing 50 nm of CdS onto SiOz-covered n Si and evaporating two A1 elechodes (source and drain) onto the CdS [45]. Similar devices were also made using CdS deposited on polyimide substrates with three (source, drain, and gate) evaporated metal electrodes and various sputtered insulator layers for the gate electrode. 

Kubo et al. [122] have covered the sensing area of a gold electrode lattice with a polyimide layer which supports an atrazine selective MIP prepared with MAA and EDMA and functional monomer and cross linker, respectively. The detection limit was 50 nM (11 ppb) with a working range up to 15 pM atrazine. Other herbicides... 

A 0.125-mm-thick polyimide substrate named Kapton HN (Good-fellow), an epoxy resin (CW2400) obtained from RS Components and self-adhesive washers of 5 mm internal diameter (19.6 mm2 of internal area) are used to construct the working electrodes. 

The three-electrode potentiostatic system is schematised in Fig. 36.1. Working electrodes are made on 5 x 5 cm2 supports of 0.125-mm-thick polyimide substrate named Kapton HN (Goodfellow). The kapton slide is cleaned with ethanol and after drying, it is covered with gold by... 

Screen printing is an excellent method for fabrication of ISEs on an industrial scale. Ag/AgCI electrodes can be screen printed onto a suitable support such as Kapton polyimide. The selective membrane is then printed onto the ISE, often with an intervening layer of a hydrogel such as poly(vinyl alcohol) soaked with NaCl solution to act as the internal reference solution. The reductions of cost associated with the mass-production of these electrodes allow them to be sold as single-use disposable devices. Also their small size relative to conventional ISEs allows them to be assembled into sensor arrays. 

An alternative approach places the Pt electrodes directly on a flexible polymer carrier [80]. Eh Lilly developed a three-electrode transducing system based on a polyimide carrier with electroadsorbed enzyme and a highly oxygen-permeable membrane covering the sensor. Such a system was tested in vivo and published results seem encouraging although the company cancelled the project. 

Polyimide microcavities (53 pm dia. and 8 pm deep) have been fabricated using two 4-pm layers sandwiched by Au/Cr electrodes [230]. 

A glassy C electrode, which was immobilized with tyrosinase, was used for amperometric detection of phenol in a polyimide chip. Phenol was enzymatically converted to catechol, which was then oxidized to quinone during detection. Chlorophenol can also be detected, but this is achieved after a dechlorination step (to phenol) using a Mg/Pd metal catalyst [229]. 

Here, 41 indicates the thin film transistors, 51 the substrate, 43 a dielectric layer, 49 polysilicon gates, 50 gate electrodes, 55 contact plugs, 56 bottom electrodes, 53 the planarization layer, 54 the mercury cadmium telluride layer and 57 the top electrode layer. The planarization layer is formed from silicon oxide, silicon nitride, silicon oxide nitride or from a polyimide. The planarization layer may be formed as a double or triple layer. 

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