New nanocluster to boost thin films for semiconductors

Oregon researchers push printed inorganic electronics to higher levels of performance by synthesizing an elusive metal-hydroxide compound in sufficient and rapidly produced yields, potentially paving the way for improved precursor inks that could boost semiconductor capabilities for large-area applications.

 

The scientists from University of Oregon substitued nitrosobenzene with nitroso-butylamine as an additive to achieve "bottom-up" production of possibly the first heterometallic gallium-indium hydroxide nanocluster. The additive acts to optimize and speed crystallization, allowing for reaction yields up to 95 percent. Comparable compounds traditionally made under caustic conditions often take months or even years to crystallize and result in low yields. The team can control the ratio of gallium and indium in the structures at molecular levels and tailor the properties for specific applications or for different performance levels.

 

The nitroso compound is still present at the end of the reaction, so it can be removed and used in future reactions and although it produces usable amounts of nanoclusters for potential semiconductor applications it is toxic. The team say that it is not a truly green-chemistry but they are looking at how it works and hope to replace it with a more benign reagent.

 

 

"Researchers working in the solid-state materials community are looking at these kinds of nanoclusters as precursors for thin films and other advanced materials, but you typically cannot get them in high enough yields," said Assistant Professor, Darren Johnson, Inorganic, organic, supramolecular & Materials chemistry, Oregon State University, also a member of the UO's Materials Science Institute. "Our synthesis, however, allows for gram-scale quantities."

 

The results represent a significant breakthrough in the way liquids are produced for semiconductor fabrication, said co-author Douglas A. Keszler, distinguished professor of chemistry at Oregon State and adjunct UO chemistry professor. "We now have new methods for pushing printed inorganic electronics to higher levels of performance within a useful class of materials."

 

Researchers in Johnson's lab have been experimenting with low-temperature production of a series of such heterometallic nanoclusters, which consist of 13 atoms and contain two different metals in the metal 13 framework, which may prove desirable for long-term applications in solid-state electronics. The nanocluster identified in the paper is labeled a Ga7In6 hydroxide.

 

For more attend Printed Electronics USA 2008  and read Inorganic and Composite Printed Electronics 2008-2018 .