Current-voltage measurement, temperature dependent

In order to imderstand these differences in the nature of the film, growth rate and thickness profile, we characterize plasma conditions (gas temperature in plasma filament, electron density, EVDF, etc.) in both cases. Using determined plasma parameters, we calculate production rates of atoms and excited molecules, simulated fluxes of excited chemical species to the inner surface of the tube, and simulated the chemical kinetics. We correlate the differences in the chemical kinetics on the differences in the film properties. OES, microphotography, current-voltage measurements and numerical simulations are used for the characterization of plasma conditions. Since the chemical kinetics depends on plasma conditions, plasma conditions and their differences between methane as well as acetylene cases are discussed first. Following this, differences in chemical kinetics will be discussed. 

Another measurement that follows the line of the Porath et al. [14] experiment was performed by Yoo et al. [75]. In this experiment, long poly(dG)-poly(dC) and poly(dA)-poly(dT) molecules were electrostatically trapped between two planar metal electrodes that were 20 nm apart (see Fig. 11) on a Si02 surface, such that they formed a bundle that was -10 nm wide. A planar gate electrode added another dimension to this measurement. The current-voltage curves showed a clear current flow through the bundle and both temperature and gate dependencies. The resistivity for the poly(dG)-poly(dC) was calculated to be 0.025 flcm. 

Additional information with respect to the mechanism of the grain boundary resistance can be obtained from temperature- and voltage-dependent impedance measurements. The grain boundary semicircle varies, for example, considerably with the applied dc bias (Fig. 39a). The current-voltage relations calculated from such bias-dependent impedance measurements are thus non-linear. In the logarithmic plot (Fig. 39b) it can be seen that the low bias regime exhibits a non-linearity factor a (= d og(I/A)/d og(U/ V)) of almost one (ohmic behavior), while at a bias value of about 0.35 V this factor changes to a x 2. 

Figure 7.31 demonstrates the very good rectifying behavior of such a Pd Schottky diode on undoped ZnO thin film. The current density ratio determined for bias voltages of +0.6 V and -3V is about 104 as shown in the inset of Fig. 7.31. The ideality factor n is about 1.5. The temperature-dependent current-voltage (IV, see Fig. 7.31) and capacitance-voltage (CV) measurements from 210 to 300 K explain the reason for the slight deviation of the ideality factor from unity and the dependence of the reverse current on the reverse bias. The barrier heights of the diode of Fig. 7.31 jy and

The electrical conductivity was obtained using the applied voltage and the measured current and dimension of the sample. The electrode was A1 plate. For dose dependence, the conductivity was measured at 300 K and at humidity of 40 % in air. For temperature dependence, the conductivity was measured in the temperature range from 300 to 393K in vacuum under pressure of 6xl0"5 Pa. 

Phonon-assisted tunneling (PhAT) model has been shown to explain properly nonlinear current-voltage characteristics and temperature dependence of conductivity in carbon nanotubes and other nanostructures of organic materials [1,2], In this paper, we want to show that this model is workable in explanation of I-V characteristics of inorganic nanodevices (Bi xSbx)2Te3 nanowires measured in a wide temperature range, 1.75-350 K, by Xiao et al. [3] and ZnSnOs nanowires presented in [4]. 

Current-Voltage, I(V), characteristics were also measured on the same unstructured film in the presence of a magnetic field applied perpendicularly to the sample surface for two different temperatures. The critical current is defined by the arbitrary electric field criterion E = Ecr= 10 V/cm. Fig. 2 shows the resulting magnetic field dependence of the critical current, I. The film shows the usually reported monotonic field dependence of Ic. The expected enhancements of the critical current for fields values close to the first matching field, H] a 1 Tesla, for T = 3.1 K was not detected. This result could be ascribed to the... 

Measurements of the temperature dependent current-voltage (J-V) characteristics of p a-SiC H/n c-Si heterojunction solar cells with different doping levels in the p a-SiC H layer have been made, and it is reported that as long as the p a-SiC H layer in these heterojunction cells is highly doped, collection problems do not occur under normal operating conditions. In some related work by the same authors, a study has been reported of the current-voltage... 

In this case, the effect observed is produced by temperature dependent current contacts and NOT by superconductivity. Here the room temperature current contact resistance was about 4K ohm. This resistance increased to around 109 ohms at 77 K, thus, over most of the temperature range of the measurement, the voltage source was not behaving as an ideal current source, resulting in an apparent drop in resistance as the temperature was lowered, producing the 220 K "onset" shown in Fig. 4. 

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