Particle-free gold metal–organic decomposition ink for inkjet printing of gold structures

• Published in: Thin solid films 2013-03, Vol.531, p.147-151
• Main Authors: Schoner, Claudia, Tuchscherer, André, Blaudeck, Thomas, Jahn, Stephan F., Baumann, Reinhard R., Lang, Heinrich
• Format: Article
• Language: English
• Subjects: Bonding; Carboxylate; Composition and phase identification; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Decomposition; Electrical properties of specific thin films; Electrically conductive; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Ethylene glycol; Exact sciences and technology; Glass; Gold; Heating; Homogeneity; Inkjet printing; Metal–organic decomposition; Physics; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2013.01.027

The application of liquid [AuO2CCH2(OCH2CH2)2OCH3(nBu3P)] (1) as a metal–organic decomposition ink containing 34.2wt.% of gold is reported. Chemical and physical properties of 1 are discussed. The ink formulated of 20wt.% of 1 in toluene (gold concentration 6.9wt.%) exhibits rheological properties well-suited for piezo inkjet printing. Conversion into electrically conductive gold was accomplished by thermal treatment optimized to provide best possible conductivity, contour accuracy, and layer homogeneity. The thermal decomposition of 1 was studied by thermogravimetry–mass spectrometry coupling experiments. It was found that at first decarboxylation takes place forming [AuCH2(OCH2CH2)2OCH3(PnBu3)], further heating cleaves the AuP bond and releases PnBu3. This resulting compound decomposes via AuC, CC and CO bond cleavage processes giving gold and appropriate organics (CxHyOz (x≥3)). The printed features exhibit conductivities of up to 1.9×107S·m−1 on glass which corresponds to 43% of bulk gold conductivity. ► Particle-free, metal–organic gold ink suitable for inkjet-printing ► Experiments are based on liquid gold(I) precursor [Au(O2CCH2(OCH2CH2)2OCH3)(nBu3P)]. ► Study of decomposition mechanism ► Study of sintering profile and conductivity