Capacitor substrate

Engineering structural ceramics (32%) Electrical and electronic ceramics (21%) Capacitors, substrates, and packages (20%) Electrical porcelain (5%)... 

Fig. 3. An overview of atomistic mechanisms involved in electroceramic components and the corresponding uses (a) ferroelectric domains capacitors and piezoelectrics, PTC thermistors (b) electronic conduction NTC thermistor (c) insulators and substrates (d) surface conduction humidity sensors (e) ferrimagnetic domains ferrite hard and soft magnets, magnetic tape (f) metal—semiconductor transition critical temperature NTC thermistor (g) ionic conduction gas sensors and batteries and (h) grain boundary phenomena varistors, boundary layer capacitors, PTC thermistors.

Fig. 10. Exploded view of a monolithic multicomponent ceramic substrate. Layers (a) signal distribution (b) resistor (c) capacitor (d) circuit protection ...

Electrically Functional. Refractory coatings are used in semiconductor devices, capacitors, resistors, magnetic tape, disk memories, superconductors, solar ceUs, and diffusion barriers to impurity contamination from the substrate to the active layer. 

Electrical and Electronic Applications. Silver neodecanoate [62804-19-7] has been used in the preparation of a capacitor-end termination composition (110), lead and stannous neodecanoate have been used in circuit-board fabrication (111), and stannous neodecanoate has been used to form patterned semiconductive tin oxide films (112). The silver salt has also been used in the preparation of ceramic superconductors (113). Neodecanoate salts of barium, copper, yttrium, and europium have been used to prepare superconducting films and patterned thin-fHm superconductors. To prepare these materials, the metal salts are deposited on a substrate, then decomposed by heat to give the thin film (114—116) or by a focused beam (electron, ion, or laser) to give the patterned thin film (117,118). The resulting films exhibit superconductivity above Hquid nitrogen temperatures. 

Arc Plasma Method The principle of NPs synthesis in this method is based on evaporation by heating and condensation by cooling. The bulk metal is evaporated by heating with electrical resistance, electron beam, or high-frequency magnetics, and subsequently the vapor of metal atoms is condensed on a substrate as a sohd film or particles. In the AP method, electrical charge filled in an external capacitor... 

Hence, Tct is seen to increase with pore density and pore radius. However, a problem appears at a porous substrate when thin films are to be deposited during metallization to form interconnections, thin-film capacitors, etc.335 Sputtered material falls deep into the pores, which affects the planarity of the deposited layer and the electrical resistivity of the oxide layer underneath.335 To cope with this effect, the porous oxide should be padded by inorganic (A1203 and Si02) or organic (polyimide, negative photoresist) layers. 

Figure 4.8. Current voltage curves for selected A1PO capacitor structures. A high-quality thermally oxidized Si02 dielectric in an identical structure is included for reference. Top contacts are 0.011-cm2 A1 dots thermally evaporated via shadow mask. Bottom contact is made via conductive substrate p++ Si in the case of 600 °C A1PO and Si02 capacitors, and sputtered Ta metal for 300 °C A1PO devices.

Major PEN film applications include substrates for Advanced Photo System (APS) [2] film, where PEN s higher modulus permits the thinner, curl-free films required. Capacitors capable of higher temperature performance in industrial motor windings also make use of PEN s properties. 

The easiest way to have different parts of the electrode surface under different bias is to disconnect them by an insulator. This method is elucidated by an experiment in which an electrochemical etch-stop technique has been used to localize defects in an array of trench capacitors. In a perfect capacitor the polysilicon in the trench is insulated from the substrate whereas it is connected in a defect capacitor, as shown in Fig. 4.15 a. If an anodic bias is applied the bulk silicon and the polysilicon in the defect trench will be etched, while the other trenches are not etched if an aqueous HF electrolyte is used, as shown in Fig. 4.15b. The reverse is true for a KOH electrolyte, because the only polysilicon electrode in the defect trench is passivated by an anodic oxide, as shown in Fig. 4.15 c. 

A macroporous silicon substrate with pores of about a micrometer and a pore depth of a few tenths of a millimeter offers a surface area enhancement of about two or three orders of magnitude compared to an unetched silicon surface. An example of such a macroporous substrate used for fabrication of a silicon capacitor (SIKO) is shown in Fig. 10.20 b. 

The change of capacitance in relation to the temperature is very small and a linear function of the substrate temperature. Unlike the change in metal film capacitors it is completely reversible. The maximum operating temperature of the capacitor chip (more than 200°) is determined by its aluminum gate. For encapsulated systems the bond contacts and the material of the package will determine the upper temperature limit. 

Fig. 9.18 (a) Schematic of the device, which was designed for simultaneous measurement of the SWNT network capacitance and conductance, (b) Dependence of the network capacitance (red) and conductance (green) on the substrate voltage, FS. The network capacitance is approximately 1/4 the value of the capacitance for a parallel-plate capacitor with an equivalent area and oxide thickness (Kong et al., 2003. With the permission from American Chemical Society) (See Color Plates)... 

In another type, mammalian cells or plasma membranes are used as electrical capacitors. Electrical impedance (El) uses the inherent electrical properties of cells to measure the parameters related to the tissue environment (Kyle et al., 1999). The mechanical contact between cell-cell and cell-substrates is measured via conductivity or El (Deng et al., 2003 ... 

Deposition of thin films is used to change the surface properties of the base material, the substrate. For example, optical properties such as transmission or reflection of lenses and other glass products, can be adjusted by applying suitable coating layer systems. Metal coatings on plastic web produce conductive coatings for film capacitors. Polymer layers on metals enhance the corrosion resistance of the substrate. 

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