The University of Minnesota, Minneapolis, announces that a team of researchers has developed a barium-tin-oxide transparent and highly conductive thin film in which they replaced elemental tin with a chemical precursor of tin. The precursor has unique, radical properties that enhance the chemical reactivity and greatly improve the metal oxide formation process. Both barium and tin are significantly cheaper than indium and are abundantly available.
“We were quite surprised at how well this unconventional approach worked the very first time we used the tin chemical precursor,” said University of Minnesota chemical engineering and materials science graduate student Abhinav Prakash, the first author of the paper. “It was a big risk, but it was quite a big breakthrough for us.”
The new process allows them to make the material with unprecedented control over thickness, composition, and defect concentration. The process should also be highly suitable for a number of other material systems in which the element is hard to oxidize. The new process is also reproducible and scalable.Researchers say that what makes this new material so unique is that it has a high conductivity, which helps electronics conduct more electricity and become more powerful. But the material also has a wide bandgap, which means light can easily pass through, making it optically transparent. In most cases, materials with wide bandgap have either low conductivity or poor transparency.
“The high conductivity and wide bandgap make this an ideal material for making optically transparent conducting films that could be used in a wide variety of electronic devices, including high power electronics, electronic displays, touchscreens, and even solar cells in which light needs to pass through the device,” said Bharat Jalan, a University of Minnesota chemical engineering and materials science professor and the lead researcher on the study.
