Ionized Cluster Beam deposition method

Toward Organic Electronic Devices Using an Ionized Cluster Beam Deposition Method... 

Tetracyanoquinodimethane (TCNQ) and related compounds [10], have been extensively investigated in the last decades. When combined with tetrathiafulvalene (TTF) and some metals such as Ag and Cu, it may show very useful properties such as electrical and optical bistability. However, to apply these organic thin films in electronic or photoelectric devices, it is of great importance that the films should exhibit few impurities and defects and it is also desired that the films crystallinity can be controlled. For these reasons, we explore an ionized cluster beam deposition method to fabricate organic crystalline thin films. 

Gao, H. J., Xue, Z. Q., and Pang, S. J., Fabrication of crystalline functional polymer thin films using an ionized cluster beam deposition method. Thin Solid Films, 292, 40-42 (1997). 

Physical vapor deposition (PVD) includes the following methods [IJ Evaporation in its simplest form involves heating the source material in vacuum to a temperature at which its partial pressure reaches about 10 - mbar. The preci.se control of composition using multiple. sources for multicomponent films is difficult. A sophisticated version of this method is molecular beam epitaxy (MBE), (requiring UHV conditions, precise control of the temperature of the sources, computer controlled shutters, etc.) capable of producing layers from multi- to monoatomic thicknes.ses. Laser-ablation-a.ssi.sted deposition (LAPVD) and cluster evaporation with ionized cluster beam deposition are among the new developments used to grow films by evaporation. 

The main characteristics of the various titanium oxide catalysts used in this chapter are summarized in Table 1. Titanium oxide thin film photocatalysts were prepared using an ionized cluster beam (ICB) deposition method [13-16]. In ICB deposition method, the titanium metal target was heated to 2200 K in a crucible and Ti vapor was introduced into the high vacuum chamber to produce Ti clusters. These clusters then reacted with O2 in die chamber and stoichiometric titanium oxide clusters were formed. Tlie ionized titanium oxide clusters formed by electron beam irradiation were accelerated by a high electric field and bombarded onto the glass substrate to form titanium oxide thin films. 

Zhou, J. K., Takeuchi, M., Zhao, X. S., Ray, A. K. and Anpo, M. (2006). Photocatalytic decomposition of formic acid under visible light irradiation over V-ion-implanted Ti02 thin film photocatalysts prepared on quartz substrate by ionized cluster beam (ICB) deposition method. Catal. Lett. 106(1-2), 67-70. 

Thin films of polyPCN (PPCN) and poly TDCN (PTDCN) for electrical activity tests were prepared by the ionized cluster beam-time-of-flight mass spectrometer (ICB-TOFMS) deposition method [23] (see also the chapters by Z. Q. Xue and H. J. Gao in this book). 

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