Characteristics of rectifying devices with thin films of polyphthalocyanine

Abstract

Chemically and thermally stable thin films of polyphthalocyanine were prepared by a simple evaporation-polymerization method. The rectifying characteristics of metal/semiconductor/ metal (MSM) type sandwich devices with the film were studied. A Schottky type device metal (Cu, Al, Ti)/polyphthalocyanine/Cu shows reproducible rectifying characteristics when Ti is selected as a counter electrode. The reproducibility is improved by pre-oxidation treatment of the surface of Cu substrate. Best electric parameters for the device are as follows: rectifying ratio = 14; threshold potential difference = 0,61 V; saturation current = 2,5 .A . cm -2 ; barrier height = 0,75 eV; diode ideality parameter = 4,23. Doping of five kinds of quinones [p-benzoquinone (p-BQ), tetrabromo-p-benzoquinone (pTBBQ) tetrachloro-p-benzoquinone (p-TCBQ)) tetrachloro-o-benzoquinone (oTCBQ) 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ)] and 2,5-cyclohexadien-l,4-diylidenedimalodinitrile (TNCR) in thin films of polyphthalocyanine affected electrocharacteristics in some cases. The diode ideality parameter decreases to 2,17 at 0,90. 1 0-6 mol . cm-' of pTBBQ, and the rectifying ratio increases to about fourteen times by doping p-TBBQ and p-TCBQ. The doped device shows a rectifying response up to 1 kHz.

Phthalocyaninatoindium(III) Acetylacetonates for Nonlinear Optics

“…The axial (acac) ligand has little influence on the position of the nonsplit Qband maximum in comparison with the chlorine ligand in 1a [7b] (697 nm) ( Figure 1). (RO) 8 PcIn(acac) (12) (R ϭ 2-ethylhexyl) was prepared by treating (RO) 8 PcH 2 (6) (R ‫؍‬ 2-ethylhexyl) with In(acac) 3 in DMF at 140°C (Scheme 2). Compound 6 was isolated from the mixture of Pcs obtained from the reaction between 1 equiv.…”

“…(Tetra-tert-butylphthalocyaninato)indium() acetylacetonate (tBu) 4 PcInacac (3) was obtained in good yield by treating the metal-free (tBu) 4 PcH 2 (2) [15] with an excess of In(acac) 3 in refluxing DMF (Scheme 1).…”

“…(tBu) 4 PcIn(acac) (3): A mixture of (tBu) 4 PcH 2 (2) [15] (0.73 g, 1 mmol) and In(acac) 3 (acac ϭ acetylacetonate) (0.12 g, 0.3 mmol) was refluxed in anhydrous DMF (15 mL) for 2 h under nitrogen. The mixture was cooled and methanol was added to precipitate the product.…”

“…The optical limiting properties of 3, 12 and 17 are compared with Scheme 1. Synthesis of (tBu) 4 PcIn(acac) (3) the ''state-of-the-art'' molecule, [7a,10] (tetra-tert-butylphthalocyaninato)indium() chloride (1a).…”

Influence of Oxygen Adsorption on Electronic Structure of Iron Phthalocyanine

“…Various Pcs compounds are mostly used in the electronics, e.g. as semiconducting devices [1][2][3], solar cells [4,5], rectifying devices [6] and, more recently, liquid crystals [7], gas sensors [8] and low-dimensional conducting materials [9].…”