Field-effect transistor performance

Ando, S. et al.. Characterization and field-effect transistor performance of heterocyclic... 

Murphy, A.R., J. Liu, C. Luscombe, D. Kavulak, J.M.J. Frechet, R.J. Kline, and M.D. McGehee. 2005. Synthesis, characteri2ation, and field-effect transistor performance of carboxylate-functionalized polythiophenes with increased air stability. Chem Mater 17 4892-4899. 

Gate oxide dielectrics are a cmcial element in the down-scaling of n- and -channel metal-oxide semiconductor field-effect transistors (MOSEETs) in CMOS technology. Ultrathin dielectric films are required, and the 12.0-nm thick layers are expected to shrink to 6.0 nm by the year 2000 (2). Gate dielectrics have been made by growing thermal oxides, whereas development has turned to the use of oxide/nitride/oxide (ONO) sandwich stmctures, or to oxynitrides, SiO N. Oxynitrides are formed by growing thermal oxides in the presence of a nitrogen source such as ammonia or nitrous oxide, N2O. Oxidation and nitridation are also performed in rapid thermal processors (RTP), which reduce the temperature exposure of a substrate. 

H. Morkoc and H. Vnlu, Factors Affecting the Performance of (Al, Ga)As/GaAs and (Al, Ga)As/InGaAs Modulation-Doped Field-Effect Transistors Microwave and Digital Applications... 

Ju, S. Lee, K. Yoon, M.-H. Facchetti, A. Marks, T. J. Janes, D. B. 2007. High performance ZnO nanowire field effect transistors with organic gate nanodielec-... 

Lin, H. C. Ye, P. D. Xuan, Y. Lu, G. Facchetti, A. Marks T. J. 2006. High-performance GaAs metal-insulator-semiconductor field-effect transistors enabled by self-assembled nanodiclcctrics. Appl.. Phys. Lett. 89 142101/1-142101/3. 

Cui, Y. Zhong, Z. Wang, D. Wang, W. U. Lieber, C. M. 2003. High performance silicon nanowire field effect transistors. Nano Lett. 3 149-152. 

Sun, B. Sirringhaus, H. 2006. Surface tension and fluid flow driven self-assembly of ordered ZnO nanorod films for high-performance field effect transistors. /. Am. Chem. Soc. 128 16231-16237. 

Control of alignment of n-conjugated polymers on the substrate is important for excellent performance of the polymer in electronic devices (e.g., higher mobility of carrier in field-effect transistors [134,136]). Details of the molecular structure and molecular assembly of PAEs will be discussed in other chapters. 

Fig. 20 Charge carrier mobility in P3HT as a function of the charge carrier concentration. Squares refer to an experiment performed on a field effect transistor while circles refer to experiments done on an electrochemically doped sample. In the latter case the mobility is inferred from the steady state current at a given doping level. Solid and dashed lines have been fitted using the theory of [101]. The fit parameters are the site separation a, the prefactor Vq in the Miller-Abrahams-type hopping rate, the inverse wavefunction decay parameter y and the dielectric constant e. From [101] with permission. Copyright (2005) by the American Institute of Physics...

Ebata H, Izawa T, Miyazaki E, Takimiya K, Ikeda M, Kuwabara H, Yui T (2007) Highly soluble [l]benzothieno[3,2-b]benzothiophene (BTBT) derivatives for high-performance, solution-processed organic field-effect transistors. J Am Chem Soc 129 15732-15733... 

Javey A, Tu R, Farmer DB et al (2005) High performance n-type carbon nanotube field-effect transistors with chemically doped contacts. Nano Lett 5 345-348... 

Ding L, Wang S, Zhang Z et al (2009) Y-contacted high-performance n-type single-walled carbon nanotube field-effect transistors scaling and comparison with Sc-contacted devices. Nano Lett 9 4209-4214... 

Katsura T, Yamamoto Y, Maehashi K et al (2008) High-performance carbon nanotube field-effect transistors with local electrolyte gates. Jpn J Appl Phys 47 2060-2063... 

Munoz-Rojas F, Femandez-Rossier J, Brey L et al (2008) Performance limits of graphene-ribbon field-effect transistors. Phys Rev B 77 045301... 

Symmetrical placement of the ion-selective membrane is typical for the conventional ISE. It helped us to define the operating principles of these sensors and most important, to highlight the importance of the interfaces. Although such electrodes are fundamentally sound and proven to be useful in practice, the future belongs to the miniaturized ion sensors. The reason for this is basic there is neither surface area nor size restriction implied in the Nernst or in the Nikolskij-Eisenman equations. Moreover, multivariate analysis (Chapter 10) enhances the information content in chemical sensing. It is predicated by the miniaturization of individual sensors. The miniaturization has led to the development of potentiometric sensors with solid internal contact. They include Coated Wire Electrodes (CWE), hybrid ion sensors, and ion-sensitive field-effect transistors. The internal contact can be a conductor, semiconductor, or even an insulator. The price to be paid for the convenience of these sensors is in the more restrictive design parameters. These must be followed in order to obtain sensors with performance comparable to the conventional symmetrical ion-selective electrodes. 

Let us pause and take an inventory of the situation up to this point. (1) We have a plausible mechanism of modulation of both components of WF of a selective layer (palladium) and (2) we have at least two methods of measurement of this effect, the macroscopic Kelvin probe and a field-effect transistor. However, the placement of the selective layer within the structure used for either measurement determines whether the effect is observable. In order to explain this caveat, we add another layer of the same metal M between Pd and the insulator in the structure shown in Fig. 6.33. This would correspond to the real life situation when we would try to connect a selective layer by a wire to the IGFET or a Kelvin Probe. It is not necessary to perform the same cycle as we did in Fig. 6.33. Instead, we add the individual energy contributions in the cycle, which begins and ends at the silicon Fermi level (moving again anticlockwise) ... 

The transistor performance is generally characterized by field-effect transistor (FET) mobility (j i), current on/off ratio (f n/f0ff), and threshold voltage (Vj)-... 

While the discussion in this chapter has focused on molecular layers on single crystal silicon surfaces, the attachment chemistries discussed here could easily be applied to functionalize silicon nanowires or nanoparticles. Silicon nanowires have been shown to exhibit interesting electrical transport characteristics and have been used to fabricate nanoscale pn junctions [95], field effect transistors [96] and biochemical sensors [97-100]. However, all these interesting phenomena have been reported on oxidized silicon nanowires. It is likely that better control over the surface properties, as could be achieved by employing some of the chemistry discussed here, could significantly improve the performance of these nanowire-based devices. From another perspective, silicon nanowires could prove extremely... 

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