Poly n- doped

In VLSI-MOS based circuits, where doped poly-crystalline silicon (poly-Si) is used as the gate electrode, the performance of the IC is limited by the RC time delays in the poly-Si runners (see for detailed discussions Murarka86, Sachdev et al.212). The main reason for this delay is the high resistivity (500 fiftcm) of n+ doped poly-Si. In addition, the trend to a larger die size worsens the problem because these poly-Si lines become longer. 

Ferraris et al. [165] chemically synthesized a processible, self-n-doped, poly(2-(2 -thienyl)3-(4-dimethyl dodecyl ammonium phenyl)thiophene triflate) using the monomer shown in Figure 1.27A. This polymer was reportedly soluble in N-methylpyrrolidone to a concentration of 53mg/mL. Similarly, the polymer was prepared electrochemically in tetramethyl ammonium trifluromethane sulfonate. The polymer prepared chemically and electrochemically exhibited reversible redox behaviour in the p- and n-doping regions. The presence of bound cations to the polymer backbone provides the ability to p- and n-... 

FI G U RE 14.4 SVET current density map showing cathodic protection of A A 2024-T3 by a n-doped poly(2,3 -dihexylthieno[3,4-ij]pyrazine) film containing an artificial defect (scratch) after 5 min immersion in 0.35 wt% (NH4>2S04. 0.05 wt% NaCl (reduction current is negative). (Reprinted from Yan, M.C. et aL, J. Electrochem. Soc., 156, C360 (color online). 2009. Reproduced with permission of The Electrochemical Society.)... 

The stoichiometry of the redox reactions of conducting polymers (n and m in reactions 1 and 2) is quite variable. Under the most widely used conditions, polypyrroles and polythiophenes can be reversibly oxidized to a level of one hole per ca. 3 monomer units (i.e., a degree of oxidation, n, of ca. 0.3).7 However, this limit is dictated by the stability of the oxidized film under the conditions employed (Section V). With particularly dry and unreactive solvents, degrees of oxidation of 0.5 can be reversibly attained,37 and for poly-(4,4 -dimethoxybithiophene), a value of n = 1 has been reported.38 Although much fewer data are available for n-doping, it appears to involve similar stoichiometries [i.e., m in Eq. (2) is typically ca. 0.3].34,39"41 Polyanilines can in principle be reversibly p-doped to one... 

In the present work, we have examined poly(N-vinylcarbazole) (abbreviated hereafter as PVCz) and pyrene-doped poly(aethyl methacrylate) (PMMA) films by using a tine-resolved fluorescence spectroscopic aethod. Fluorescence spectra and their dynanic behavior of the forner fila were elucidated with a high intensity laser pulse and a streak camera, which nakes it possible to neasure dynaaics just upon laser ablation. This aethod reveals aolecular and electronic aspects of laser ablation phenomena (17). For the latter fila a laser pulse with weak intensity was used for characterizing the ablated and Basked areas. On the basis of these results, we demonstrate a high potential of fluorescence spectroscopy in aolecular studies on laser ablation and consider its mechanism. Experimental... 

Li G, Mianami N (2003) Increase of photoluminescence from fullerenes-doped poly (alkyl methacrylate) under laser irradiation. Journal of Photoluminescence 104 207. 

Recently, intense interest has been paid on doped poly(acetylene) because its film 68) showed markedly high conductivity on doping69 70 71 and the n- and p-type conductivities are depending on the dopants. The confirmation of p-n junction formation with the p- and n-type -fCH T, has roused great expectations to produce a polymer film solar cell.72a)... 

The doped poly(acetylene) forms various junctions such as a) a p-n junction from p- and n- -f CH, b) a hetero-Schottky junction from the inorganic semiconductor and metalic -f CH-, and c) a heterojunction from the inorganic semiconductor and semiconducting The bandgaps of -(-CH (trans- 0.6 eV, cis- 0.9 eV)... 

In poly[2,5-bis(3,4-ethylene-dioxy-2-thienyl)pyridine], a copolymer of thiophene and pyridine in a 2 1 ratio, the effective HOMO and LUMO energy levels of the ir-system are controlled in such a way that both p-doped and n-doped states are accessible (Scheme 9) [43]. The thin fdms display multicolor... 

If the principles, so far outlined, are valid then it is to be expected that n-type doping of polyacetylene would lead to a decrease in stability towards oxidation, and this is indeed so 578). However, the introduction of electrons into the chain can also give a new instability in that the oxidation potential can fall to the point where the polymer is able to reduce water and it becomes hydrolytically unstable. Thus n-type doped polyacetylene reacts rapidly with water and with alcohols, with partial hydrogenation of the chain and a rapid decrease in conductivity 579,580,581). Whitney and Wnek 582) have used the reaction of n-doped polyacetylene with alkyl halides and other reagents to prepare functionalized poly acetylene films. 

H NMR study of I2 doped poly[2-buthoxy-5-methoxy phenylene vinylene] (PBMPV) has been carried out by Lee et al.114 They found magnetization recovery to follow a stretched-exponential form M(f) =Mo[l — exp(f/Ti) ] with n = 0.8 0.03, which is characteristic of a system with distribution of the correlation time. 1/Tj versus/ 172 in samples with different conductivity follows/ 172 dependence over 20 40 MPIz range indicating the main SLR is ID spin diffusion. A correlation between 1/T1 and dc conductivity has been made which is found follow a simple power law. 

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