Organic thin films, molecular

This approach works quite well for species at metal surfaces. It has been used extensively in recent years to ascertain information about organic thin films on metal surfaces. Of particular interest in many of these studies, and indeed the real forte of this technique, has been the deterrnination of molecular orientation on surfaces from such studies. Few other techniques are quite so useful for unambiguously ascertaining molecular orientation. 

Holmlin RE, Ismagilov RF, Haag R, Mujica V, Ratner MA, Rampi MA, Whitesides GM (2001) Correlating electron transport and molecular structure in organic thin films. Angew Chem Int Ed 40 2316-2320... 

Peumans, P. Uchida, S. Forrest, S. R. 2003. Efficient bulk heterojunction photovoltaic cells using small-molecular-weight organic thin films. Nature 425 158-162. 

Molecular organized thin films containing thiophene derivatives. 

Fabrication of organic thin films based on sponfaneous molecular assembly has been considered as one of fhe powerful approaches to create novel supramolecular systems. In this context, multilayer films were fabricated by layer-by-layer electrostatic deposition techniques based on the electrostatic interaction between dsDNA and the positively charged polymer poly(diallyldimethylammonium chloride) (PDDA) on GC surfaces. A uniform assembly of PDDA/DNA multilayer films was achieved, based on the adsorption of the negatively charged DNA molecules on the positively charged substrate [55]. 

Figure 3.18. Thin TTF-TCNQ film (thickness 1 um) HV-grown on a KCl(lOO) substrate, (a) Topography and (b) amplitude TMAFM images. The scale is 5 p.m x 5 ]xm. (c) FTIR spectra of the CN stretching mode in neutral TCNQ (powder) and in a TTF-TCNQ thin film (thickness 1 um) HV-grown on KBr(lOO). Reprinted from Surface Science, Vol. 482 85, C. Rojas, J. Caro, M. Grioni and J. Fraxedas, Surface characterization of metallic molecular organic thin films tetrathiaful-valene tetracyanoquinodimethane, 546-551, Copyright (2001), with permission from Elsevier.

Figure 5.11. TMAFM image of a thin film (thickness 1 am) of a -/7-NPNN on NaCl(lOO) 1 am x 1 am. Reprinted from Surface Science, Vol. 415, J. Fraxedas, J. Caro, A. Figueras, R Gorostiza andF. SsLnz,Dislocationhollow cores observedon surfaces of molecular organic thin films p-nitrophenyl nitronyl nitroxide radical, 241-250, Copyright (1998), with permission from Elsevier.

Heteroacene derivatives, (I), were prepared by Park et al. (1), which were effective as organic thin-film transistors. Low-molecular-weight thiophene oligomers were also prepared by Hahn et aL (2) and used as organic semiconductors. 

M = Tb, Lu) into organic thin-film transistors by LB technique and reported their field effect mobility, which represented the first report for p-type OFETs based on bis(phthalocyaninato) rare earth complexes prepared via LB method [88], Due to the highly ordered molecular arrangement of M(Pc)[Pc(OC8Hi7)g] (M = Tb, Lu) in LB films and the appropriate HOMO energy level of these double-deckers relative to the Au source-drain electrodes, the OFETs reported in that work exhibited higher hole transfer mobility of 1.7 x 10-3 cm2 V-1 s-1 in comparison with those fabricated from monomeric phthalocyanine LB films. 

The organic thin films used in lithography are polymer casting films, Langmuir-Blodgett (LB) films, SAMs and plasma-polymerized films. The molecular designs and syntheses of organic monolayer materials are studied for SPNL resists [89]. 

Penmans P. Yakimov A. Forrest S. R. Small molecular weight organic thin-film photodetectors and solar cells (2003) J. Appl. Phys., 93 3693-3723. 

T. Tsutsui, C. Adachi, S. Saito, Electroluminescence in Organic Thin Films, in Photochemical Progress in Organized Molecular Systems (Ed. K. Honda) Elsevier Science Publishers, B. V., Amsterdam 1991, 437-450. 

Most of the phenomena described in this monograph on photoreactive organic thin films are based on the isomerization of units deliberately built into molecules, molecular assemblies, or polymers. Most especially, the spectroscopic and isomerization behavior of these units determines the switching and triggering properties of the photoreactive systems and devices. Information storage and nonlinear optical properties, as well as photo-control of equilibria and of polymer, membrane, and other properties are exploited in applications. 

---