Field-effect transistor, schematic

Fig. 12.13 An organic thin-film field-effect transistor, schematic. The current Id in a weakly semiconducting organic film (black) between two electrodes S (source) and D (drain) can be controlled by the gate (G) voltage Vc- The latter influences charge carriers capacitively in a thin layer of the...

Figure Bl.22.4. Differential IR absorption spectra from a metal-oxide silicon field-effect transistor (MOSFET) as a fiinction of gate voltage (or inversion layer density, n, which is the parameter reported in the figure). Clear peaks are seen in these spectra for the 0-1, 0-2 and 0-3 inter-electric-field subband transitions that develop for charge carriers when confined to a narrow (<100 A) region near the oxide-semiconductor interface. The inset shows a schematic representation of the attenuated total reflection (ATR) arrangement used in these experiments. These data provide an example of the use of ATR IR spectroscopy for the probing of electronic states in semiconductor surfaces [44]-...

The measurement of changes of the surface potential Vo at the interface between an insulator and a solution is made possible by incorporating a thin film of that insulator in an electrolyte/insulator/silicon (EIS) structure. The surface potential of the silicon can be determined either by measuring the capacitance of the structure, or by fabricating a field effect transistor to measure the lateral current flow. In the latter case, the device is called an ion-sensitive field effect transistor (ISFET). Figure 1 shows a schematic representation of an ISFET structure. The first authors to suggest the application of ISFETs or EIS capacitors as a measurement tool to determine the surface potential of insulators were Schenck (15) and Cichos and Geidel (16). 

Figure 4.22 Schematic diagram of a field effect transistor. The silicon-silicon dioxide system exhibits good semiconductor characteristics for use in FETs. The free charge carrier concentration, and hence the conductivity, of silicon can be increased by doping with impurities such as boron. This results in p-type silicon, the p describing the presence of excess positive mobile charges present. Silicon can also be doped with other impurities to form n-type silicon with an excess of negative mobile charges.

Fig. 38. Hall resistance Rnall of an insulated gate (ln.Mn)As field-effect transistor at 22.5 K as a function of the magnetic field for three different gate voltages. /tnaii s proportional to the magnetization of the (In.Mn)As channel. Upper right inset shows the temperature dependence of / Hall- Let inset shows schematically the gate voltage control of the hole concentration and the conesponding change of the magnetic phase (Ohno et al. 2000).

Figure 19.8—A selective electrode designed from a MOSFET (metal oxide semiconductor field effect transistor). A specific reaction can be monitored by putting an enzyme in contact with the electrodes. This schematic shows the three electrodes used for amperometric measurement.

Fig. 16. Schematic diagrams (not to scale) showing, in the upper diagram a metal-insulotor-semiconductor structure which forms an integral part of the field effect transistor shown in the luwer diagram...

MOSFETs. The metal-oxide-semiconductor field effect transistor (MOSFET or MOS transistor) (8) is the most important device for very-large-scale integrated circuits, and it is used extensively in memories and microprocessors. MOSFETs consume little power and can be scaled down readily. The process technology for MOSFETs is typically less complex than that for bipolar devices. Figure 12 shows a three-dimensional view of an n-channel MOS (NMOS) transistor and a schematic cross section. The device can be viewed as two p-n junctions separated by a MOS capacitor that consists of a p-type semiconductor with an oxide film and a metal film on top of the oxide. 

Fig. 6.20 Schematic of ion-sensitive field-effect transistor (ISFET)...

Fig. 6.30 Schematic diagram of the suspended gate field-effect transistor (SGFET). The selective layer is typically deposited electrochemically...

Figure 3. Ionic leakage paths in chemfet structures a.Schematic illustration of ionic leakage paths around the chemically sensitive membrane. Leakage through the membrane also occurs but is not illustrated b. Schematic illustration of leakage at the surface of a standard ion sensitive field effect transistor.

A schematic view of a microdielectrometer sensor is shown in Fig. 8 and illustrates the electrode array, the field-effect transistors and a silicon diode temperature indicator 15) which functions as a moderate accuracy ( 2 °C) thermometer between room temperature and 250 °C. The sensor is used either by placing a small sample of resin over the electrodes, or by embedding the sensor in a reaction vessel or laminate. Since all dielectric and conductivity properties are temperature dependent, the ability to make a temperature measurement at the same point as the dielectric measurement is a useful feature of this technique. 

Fig. 8. Schematic top view of actual microdielectrometer sensor, illustrating the comb electrode structure, field effect transistors and thermal diode temperature indicator. (Reprinted with permission of Micromet Instruments, Inc.)...

Figure 2. (a) Schematic cross section of an organic field-effect transistor (OFET). (b) Schematic cross section of an organic electrochemical transistor (OECT). The applied source-drain voltage Vd and gate voltage Vg are also shown. 

The attractiveness of silicon as a semiconductor material for ICs derives in part from the feet that this important material forms a naturally insulating surface oxide. Use is made of this fact, for example, in metal-oxide-semiconductor (MOS) field-effect transistors (FET), where the oxide serves as the gate insulator. No such naturally insulating oxide occurs with any of the compound semiconductors that offer improved performance over silicon in many device apphcations. Roberts et al. (38) demonstrated the feasibiUty of such metal-insulator-semiconductor (MIS) structures as FETs and chemical sensors shown schematically in Figure 1.23. These researchers... 

Fig. 8.12. Nanoelectronic devices (a) Schematic diagram [163] for a carbon NT-FET. Vsd, source-drain voltage Vg, gate voltage. Reproduced from ref [163], with permission, (b) Scanning tunneling microscope (STM) picture of a SWNT field-effect transistor made using the design of (a) the aluminum strip is overcoated with aluminum oxide, (c) Image and overlaying schematic representation for the effect of electrical pulses in removing...

Figure 4.3 Schematic of a metal oxide semiconductor field effect transistor (courtesy of U. Ravaioli, University of Illinois at Urbana-Champaign).

Figure 14-6. Schematic view of three kinds of field-effect transistors (FET) (a) metal-insulator-semiconductor FET (MISFET), (b) metal-semiconductor FET (MESFET), (c) thin-film transistor (TFT).

Figure 19. Schematic diagram of the (a) field-effect transistor and (b) ion-selective field-effect transistor (1) base, (2) source and drain, (3) insulating layer, (4) gate, (5) low-ohmic electric circuit, (6) high-ohmic electric circuit, (7) ion-selective membrane, (8) reference electrode, and (9) electrolyte solution under investigation.

Figure 12.1 Schematic of an organic field effect transistor with its relevant interfaces. The molecules are shown in green.

Figure 8.1 Schematic cross section of our pentacene (Pc) organic field effect transistors.

Figure 11.1 Schematic layout of organic field effect transistors with top (a) and bottom contacts (b).

Figure 3.14 (a) SEM images for single-walled carbon nanotubes (SWCNT) synthesized by chemical vapor deposition (CVD) with iron-rich ceramic particles derived from patterned PS-fc-PFF.MS islands as catalyst. (From Lu et al.57 Reproduced with permission.) (b) Schematic and AFM height image (11 pm2) of high-throughput field-effect transistors (FETs) from SWCNTs afforded from pyrolyzed PS- -PFEMS films. (From Lastella et al.59 Reproduced with permission.)... 

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