Capacitance-voltage characteristics

The capacitance, C, of the transistor can be changed by depleting or accumulating charge in the semiconductor at the interface with the insulator. In depletion, the 

The inset in the right panel shows the The samples are measured under vacuum 

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]. 

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Fig. 5. NMOS capacitance voltage characteristics where C is the oxide capacitance, A shows low frequency characteristics, and B shows high frequency characteristics. At low frequencies C approaches C for negative voltages (accumulation) and positive voltages (inversion). In the flat-band (FB) condition there is no voltage difference between the semiconductor s surface and bulk. The threshold voltage, Dp for channel formation is the point where the...

Capacitance-voltage characteristics of a bare and functionalized EIS structure... 

CAPACITANCE-VOLTAGE CHARACTERISTICS OF A BARE AND FUNCTIONALIZED EIS STRUCTURE... 

Figure 2.2 (a) Capacitance voltage characteristics of an n-type SiC-based capacitor at 400°C with a gate of sputtered Pt. (b) Current voltage characteristics of a Schottky diode at 400°C with a porous Pt gate electrode. 

Sodium contamination and drift effects have traditionally been measured using static bias-temperature stress on metal-oxide-silicon (MOS) capacitors (7). This technique depends upon the perfection of the oxidized silicon interface to permit its use as a sensitive detector of charges induced in the silicon surface as a result of the density and distribution of mobile ions in the oxide above it. To measure the sodium ion barrier properties of another insulator by an analogous procedure, oxidized silicon samples would be coated with the film in question, a measured amount of sodium contamination would be placed on the surface, and a top electrode would be affixed to attempt to drift the sodium through the film with an applied dc bias voltage. Resulting inward motion of the sodium would be sensed by shifts in the MOS capacitance-voltage characteristic. 

Despite these potential difficulties, Vuillaume and co-workers have reported electrical characteristics of octadecyl (Cig) monolayers on Si(lll) using evaporated A1 contacts [25,78]. These metal/monolayer/silicon junctions exhibit the expected capacitance-voltage characteristics for these types of junctions. Figure 13 shows the measured C-V curves for moderately... 

Capacitance-voltage characteristics of the samples at room temperature have been recorded. Temperature dependences of resistance and capacitance of the samples were measured as well by the two-probe method. The measurements have been carried out in temperature range of 20-100 C. 

Figure 2, Capacitance-voltage characteristics of VO2 thin films on Si02/Si substrate.

Design and fabrication of ISFET was described in Ref. [88] The interest in ISFET arises chiefly from their application as pH and ion sensors. A graphical procedure to find PZC from capacitance-voltage characteristics of electrolyte-insulator-semiconductor and metal-insulator-semiconductor structures was discussed [89]. Due to the choice of electrolyte (2 mol dm Na2S04) the PZC values reported in this study (2.5 for Si02, 2.8 for Ta20s and 3-3.4 for Si3N4) are not likely to be the pristine values due to specific adsorption of anions. 

Poghossian, A.A., Determination of the pHp, of insulators surface from capacitance-voltage characteristics of MIS and EIS structures. Sensors Actuators B, 44, 551, 1997. 

Figure 21.9 Top schematic of our capacitors. Bottom capacitance-voltage characteristic of a 100 nm Si02/110 nm P(VDF-TrFE) sample at room temperature and at 100 °C. The inset shows the flathand voltage shifts dependent on temperature.

A third strategy for determining the threshold voltage is to measure the capacitance-voltage characteristic of the transistor (or C — V curve), which directly indicates the carrier density [116]. The capacitance is measured between the source and drain held together and the gate (Fig. 6.7 (a)). 

In the fabrication of hyperabrupt diodes such as varactors, the flexibility in doping profiles that can be produced by ion implantation allows a wide range of capacitance-voltage characteristics to be designed. 

Chattopadhyay, R Sanyal, S. 1995. Capacitance-voltage characteristics of Schottky barrier diode in the presence of deep-level impurities and series resistance. Applied Surface Science, 89 205-209. 

Figure 13.11 Current-voltage and capacitance-voltage characteristics of metal/...

Fig. 2.28 Operating characteristics of heterostructure-based gas sensors, (a) CuO SnOj heterostructures configuration, (b) I-V characteristics in air and 100 ppm H S in

Studies of capacitance-voltage characteristics were done on metal insulator semiconductor (MIS) structures. The MIS structure consists of PCBM spin-coated on top of DNA-CTMA. For the metal electrode in the MIS device Cr/Au was chosen as the bottom as well as top electrode. Similarly, MIM devices were also fabricated and studied. For the MIM devices characteristics of capacitance vs frequency show no significant change in capacitance throughout the measured frequency range (see Fig. 21). On the other hand, MIS devices show rise in capacitance between frequency ranges of 10 to 10 Hz, corresponding to the dielectric relaxation of the PCBM semiconductor. At lower frequencies, capacitance further increases to an... 

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