Parasitic current measurement

Using impedance spectroscopy we measured transistors with solution processed pentacene as the semiconductor. Fabrication details are discussed in Section 13.3.1. We have made use of a ring-type transistor, in which the source electrode forms a closed ring around the transistor channel and the drain electrode, at which the current is monitored. Using this geometry, the measurements are insensitive to parasitic currents that may flow outside the transistor area [29]. 

Since the electrical resistance of the effiuent and parasitic currents are minimal at high level of impurities, specihc interest in electrically assisted membrane processes could increase due to more strict laws and legislation around effluents. The depletion of freshwater resources and the necessity to process brackish or seawater to produce potable water could promote the use of electrically assisted membrane processes in the future. Electrodialysis will have to compete with pressure-driven membrane processes such as reverse osmosis. The growing awareness of the unique cleaning ability of electrically ionized water (EIW) [47], a byproduct of electrodialysis, may be a factor to consider in the choice between ED and RO systems. NMR relaxation measurements were used to determine the water cluster size of electrically ionized water EIW. It is known that the water cluster size of EIW is signihcantly smaller than that of tap water. The smaller water cluster size is believed to enhance the penetration and extractive properties of EIW. Recently, EIW has been produced and used in several cleaning processes [47] in industry. 

The steady state crossover rates for trimethoxymethane and methanol have been determined by measuring the carbon dioxide content in the cathode stream. The crossover rates for both fuels were found to decrease with increasing current density, and also increase with temperature. When the crossover rates of TMM are compared with those of methanol in terms of the amount of moles per second, TMM was observed to have lower crossover at low current densities. This observation can be explained as being due to the physically larger size of a TMM molecule compared with methanol. However, when the crossover rate is expressed as a parasitic current density, the value... 

Higher parasitic currents that lower current efficiency and cause corrosion Malfunction of a unit cell can be difficult to locate No flow measurements to the individual cells... 

On another front, to accomplish electrical measurments of individual NWs, free of parasitic effects, and to develop competitive sensors, various fabrication and characterization strategies have been evaluated. For instance, low-current measur ent protocols have been found to aUow the devices to operate long-term withont degradation of their performance (Hemandez-Ramirez et al. 2007a, b). Thus the present state of development of NW-based technologies has led to complete and weh-controUed characterization of proof-of-concept devices, which were previously imattainable (Comini et al. 2009). 

As the voltage reference points and are nonzero, a finite load on both voltage electrodes may still allow parasitic current Ip iTK flow. This parasitic current flows out from the sample and may create an error in the total sample current measurement that is negligible as long as Z, p p SAMPLE Measured sample current becomes ... 

It becomes obvious from Eq. 8-22 that for the optimal measurement MEASURED SAMPLE Condition should exist so Therefore, in addition to the need to suppress parasitic current by maintain-... 

The schematic of the temperature sensor on the bulk chip is shown in Fig. 5.3. The bulk chip temperature is measured via the voltage difference between a pair of diode-connected pnp-transistors (parasitic transistors as available in the CMOS process, collectors tied to substrate) working at different current densities. Transistor Qi is biased with a current of 40 pA, and transistor Q2 is biased with a current of 10 pA. 

The result of measurement is the maximal parasitic voltage of alternating current. All the measured values have been reduced by 300 to make calculation easier and are shown in Table 2.66. Do the analysis of variance. 

With respect to the equivalent circuit in Figure 3.3, an evaluation of the known methods for hysteresis measurements will be given, in view of the effective parasitic capacitance and the influence of reflection. Well known methods to record the hysteresis loop of ferroelectric capacitors by measuring the current response are Sawyer Tower, Virtual Ground, and Shunt measurement as shown in Figure 3.4. 

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