Frequency capacitively coupled

Dielectric constant/loss The value of the dielectric constant is important in the wire because of the effect that it has in coupling currents in one set of wires into another set of wires. The higher the dielectric constant, the higher the value capacitor that is formed between two wires. The capacitor thus formed is a signal carrying device at the frequencies used in communications and a signal can be capacitively coupled from one circuit to another. PE is the preferred choice for insulation of communication wire because of its low dielectric constant that minimizes the intercircuit coupling effect usually referred to as cross-talk. 

The plasma potential is about 25 V (Figure 63a). This value of the plasma potential is typical for the silane plasmas in the asymmetric capacitively coupled RF reactors as used in the ASTER deposition system, and is also commonly found in argon or hydrogen plasmas [170, 280, 327]. From the considerable decrease of the dc self-bias with increasing frequency (Figure 63a) it is inferred that the... 

In contrast, Heintze and Zedlitz [236] also presented data on the plasma potential as function of frequency in silane plasmas the plasma potential varies from about 27 V at 35 MHz to about 20 V at 180 MHz. Moreover, Dutta et al. [284] used a symmetric capacitively coupled RF reactor and estimated the plasma potential in their system from the applied voltage at the powered electrode. A decrease of the plasma potential from 45 V at 13.56 MHz to only 15 V at 70 MHz is observed. This difference in behavior is thought to be solely due to the different reactor geometries. 

Dielectric losses arise from the direct capacitive coupling of the coil and the sample. Areas of high dielectric loss are associated with the presence of axial electric fields, which exist half way along the length of the solenoid, for example. Dielectric losses can be modeled by the circuit given in Figure 2.5.3. The other major noise source arises from the coil itself, in the form of an equivalent series resistance, Rcoii. Exact calculations of noise in solenoidal coils at high frequencies and small diameters are complex, and involve considerations of the proximity and skin depth effects [23],... 

Most of plasma polymerizations have been carried out in the frequency range from 50 Hz to 13.56 MHz with using the capacitively coupled discharge system (.4,16). For the inductively coupled discharge system, a frequency of 13.56 MHz was mostly used as a discharge frequency (17,18). In this paper, the discussion will be concentrated on the discharge in the capacitively coupled discharge system. 

A four-electrode capacitively coupled (contactless) detector has been integrated on a Pyrex glass chip for detection of peptides (1 mM) and cations (5 mM K+, Na+, Li+). The A1 electrode (500 nm Al/100 nm Ti) was deposited in a 600-nm-deep trench and was covered with a thin dielectric layer (30-nm SiC). The other parts of the channel were covered and insulated with Si3 N4 (160 nm). To avoid gas bubble formation after dielectric breakdown, the electric field for separation was limited to 50 V/cm [145]. This four-electrode configuration allows for sensitive detection at different background conductivities without the need of adjusting the measurement frequency [328]. 

The principle of the resonator is the same as that of a vibrating string and in the illustrated example one end of the line is maintained at ground potential (the node) and the other is the antinode. The permittivity of the surroundings determine the length of the line for a particular resonance frequency and, in this case, also serves to capacitively couple energy into and out of the resonator. 

Capacitivelv coupled noise. Any two objects form a capacitor ( stray capacitance ) which establishes a path for high frequency signals. Noise which is capacitively coupled into a circuit is basically current noise which is converted to voltage by an impedance between the two objects. 

Fig. 37. Impedance spectra obtained by means of microelectrodes on a Fe-doped SrTiC>3 polycrystal at 585 K. (a) Spectrum measured with microelectrodes on one and the same grain demonstrating that only a bulk semicircle occurs, (b) Spectrum measured across a grain boundary, (c) Spectrum measured across another grain boundary there is a pronounced shoulder at the high frequency part of the grain boundary arc. (d) Bulk arc of spectrum (c) indicating the loop due to capacitive coupling to the ground.

High-frequency discharges at low power and with capacitive power coupling, known as the stabilized capacitively coupled plasma (SCP), as described by Gross et al. [432]... 

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