Will power electronics soon say goodbye to gallium-nitride transistors? Possibly, according to researchers from the University of Utah and the University of Minnesota. Though there is still a lot of work to do, the combination of strontium titanate (STO) and neodymium titanate (NTO) looks like a promising way of synthesizing a material that has a much higher conductivity than both ordinary silicon and gallium nitride.

“When I look at the future, I see that we can perhaps improve conductivity by an order of magnitude through optimizing of the materials growth,” says University of Minnesota chemical engineering and materials science assistant professor Bharat Jalan. “We are bringing the possibility of high power, low energy oxide electronics closer to reality. It’s fundamentally a different road toward power electronics, and the results are very exciting” he says. “But we still need to do more research.”

Jalan worked with University of Utah electrical and computer engineering professor Ajay Nahata; Utah graduate students Sara Arezoomandan, Hugo Condori Quispe, Ashish Chanana; and Minnesota graduate student Peng Xu on a recent effort to measure the conductivity of the STO/NTO combination. Specifically, they studied the two-dimensional electron gas at the interface of NdTiO₃ and SrTiO₃ to understand its nanoscale transport properties. They say that at electron densities approaching 10¹⁵ cm⁻², a measurement technique employing terahertz spectroscopy shows conductivity levels that are up to six times larger than those extracted from dc electrical measurements. Moreover, they say their measurements show that because of an enhanced
nanoscale mobility, the two-dimensional electron gas (2DEG) at the interface between NTO and STO can reach conductivity levels that are on the same order of those in AlGaN/GaN or in typical quality large-area CVD graphene on silicon substrates.

More info: The University of Utah put out a press release about the work, available here.