MOCVD-Derived Highly Transparent, Conductive Zinc- and Tin-Doped Indium Oxide Thin Films:  Precursor Synthesis, Metastable Phase Film Growth and Characterization, and Application as Anodes in Polymer Light-Emitting Diodes

Abstract

Four diamine adducts of bis(hexafluoroacetylacetonato)zinc [Zn(hfa)(2).(diamine)] can be synthesized in a single-step reaction. Single crystal X-ray diffraction studies reveal monomeric, six-coordinate structures. The thermal stabilities and vapor phase transport properties of these new complexes are considerably greater than those of conventional solid zinc metal-organic chemical vapor deposition (MOCVD) precursors. One of the complexes in the series, bis(1,1,1,5,5,5-hexafluoro-2,4-pentadionato)(N,N'-diethylethylenediamine)zinc, is particularly effective in the growth of thin films of the transparent conducting oxide Zn-In-Sn-O (ZITO) because of its superior volatility and low melting point of 64 degrees C. ZITO thin films with In contents ranging from 40 to 70 cation % (a metastable phase) were grown by low-pressure MOCVD. These films exhibit conductivity as high as 2900 S/cm and optical transparency comparable to or greater than that of commercial Sn-doped indium oxide (ITO) films. ZITO films with the nominal composition of ZnIn(2.0)Sn(1.5)O(z)() were used in fabrication of polymer light-emitting diodes. These devices exhibit light outputs and current efficiencies almost 70% greater than those of ITO-based control devices.

Temperature‐Controlled Synthesis and Photocatalytic Performance of ZnO Nanoplatelets

“…Precursor Synthesis and Characterization: Zn(hfa) 2 ÁTMEDA was synthesized according to a recently described literature procedure [32]. The compound was subsequently purified by vacuum sublimation (90°C, 10 -2 mbar), until its melting point fell in the range 106-108°C (yield for the complete synthesis = 63 %).…”

“…In this work, we report for the first time the catalyst-free CVD of ZnO nanoplatelets on Si(100) from Zn(hfa) 2 ÁTMEDA, a second-generation source, whose synthesis was recently proposed by Ni et al [32] Such a precursor possesses a high volatility, and prevents undesired oligomerization phenomena thanks to the complete saturation of the Zn II coordination sphere. [32] To the best of our knowledge, despite the use of various base-stabilized Zn(hfa) 2 in CVD processes having already been reported, [32] the chosen compound has never been adopted, to date, in CVD applications. Adopting the above precursor, zinc oxide nanoplatelets were grown by CVD on Si(100).…”

p -Type semiconducting nickel oxide as an efficiency-enhancing anode interfacial layer in polymer bulk-heterojunction solar cells

“…This device design has achieved confirmed power efficiencies up to 4% (10). Despite these positive characteristics, note that aqueous PEDOT:PSS dispersions are at pH ϳ 1 and corrosive to the ITO anode (30,31). Furthermore, many researchers find that PE-DOT:PSS depositions yield inconsistent film morphologies and electrical properties in accord with the demonstrated electrical inhomogeneity of these films (32,33).…”

One‐Pot Synthesis of Highly Conductive Indium Tin Oxide Nanocrystals

“…[4][5][6] Conventionally, ITO layers are prepared by using gas-phase deposition techniques, for example, magnetron sputtering, chemical vapor deposition, vacuum evaporation, and spray pyrolysis. [7][8][9] Under optimum conditions resistivities on the order of 10 -4 X cm, sheet resistivities of ca. 10 X/ᮀ, and transparencies of 85-90 % can be achieved.…”