Organic semiconductor phthalocyanines

Keywords Field effect transistors (FETs) Organic semiconductor Phthalocyanine Porphyrin Tetrapyrrole... 

Organic semiconductors are becoming increasingly important in the fabrication of electronic devices. For electron transport, metal complex pigments, such as hexa-deca-fluoro copper phthalocyanine (76), are showing potential.79... 

I.G. Hill and A. Kahn, Combined photoemission in vacuotransport study of the indium tin oxide/copper phthalocyanine/A, iV8-diphenyl- N, NR-bis. l-naphthyl.-l,18biphenyM,49diamine molecular organic semiconductor system, J. Appl. Phys., 86 2116-2122 (1991). 

A semiconductor sensor-based instrument was described for determination of the composition and concentrations of vapors of organic nitro compounds and nitrogen dioxide in the atmosphere. Four organic semiconductor sensors [e.g. aluminum phthalocyanine fluoride (222a)] were tested in conjunction with platinized platinum preconcentrators sensitivity is to ppm levels of nitrobenzene450. 

Photoelectrochemical behavior of metal phthalocyanine solid films (p-type photoconductors) have been studied at both metal (93,94,95,96) and semiconductor (97,98) electrodes. Copper phthalocyanine vacuum-deposited on a Sn02 OTE (97) displayed photocurrents with signs depending on the thickness of film as well as the electrode potential. Besides anodic photocurrents due to normal dye sensitization phenomenon on an n-type semiconductor, enhanced cathodic photocurrents were observed with thicker films due to a bulk effect (p-type photoconductivity) of the dye layer. Meier et al. (9j>) studied the cathodic photocurrent behavior of various metal phthalocyanines on platinum electrodes where the dye layer acted as a typical p-type organic semiconductor. 

Organic Semiconductors of Phthalocyanine Compounds for Field Effect Transistors (FETs)... 

Due to the great potential applications and the widespread interests of OFETs, several review articles with emphasis on different aspects of OFETs have been published [8-13], However, despite the extensive studies and increasing research interests in phthalocyanine as well as porphyrin semiconductors, there is still no review article that systematically generalizes the research achievements in the field of tetrapyrrole organic semiconductors for OFETs. Thus, the present contribution should interest scientists in both industrial and theoretical fields. The main contents of this chapter is as follows Firstly, some basic introduction of the structure and characteristics of OFET is provided then theoretical factors that influence the performance of OFET devices is discussed finally, the progress in phthalocyanine-based OFETs in the order of p-type, n-type, and ambipolar semiconductors is summarized. 

Phthalocyanines are organic semiconductors that strongly absorb visible light, and have been extensively investigated for use in photovoltaic (11), and photoelectrochemical cells (12.). The results however were somewhat inconsistent, and this was probably due to the presence of impurities which were not always clearly identified. Commercially available phthalocyanine was analyzed in order to determine the trace elements present, as well as the effect of heat treatment on the iodine contamination. The X-ray spectra, for an accumulated charge of 15 (1C, from untreated and from H2PC purified for... 

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