EMA Bray plen

EMA Bray plen Q

One sure sign of a successful talk is a queue of audience members with follow-up questions. EMA’s opening plenary speaker James Bray (blue shirt) answers a question from ACerS president David Green (yellow sweater). Credit: ACerS.

The deep freeze and latest round of snowstorms afflicting North America and dipping into Central Florida seem to have had little affect on the Electronic Materials and Applications conference in Orlando this week. It is chilly, but the sun is shining and the science is stimulating. This meeting, now in its fifth year and a collaboration between the Electronics Division and the Basic Science Division, welcomed nearly 300 scientists and engineers from the US and abroad.

Yesterday, James Bray opened the conference with the plenary talk, “Electrical and Electronic Materials for Industrial Application.” Bray is chief scientist for electrical technologies and systems at GE Global Research. In his talk he outlined the materials challenges GE has identified for three product categories: electrical insulation, energy storage, and power electronics. A common theme that emerged across all three is the need for materials that allow devices to operate at elevated temperatures. Also on the wish list are materials that will allow devices to operate at higher voltages, with lower losses, higher efficiency, and—by the way—cheaper.

Bray spent most of his time discussing energy storage and power electronics, which present some interesting opportunities and commensurate materials challenges. He characterized the area of energy storage as increasingly important. For example, as hybrid vehicles gain popularity, automakers feel increasing pressure to reduce battery size. Interestingly, he pointed out that GE founder Thomas Edison and early GE engineer Charles Steinmetz (aka Karl Steinmetz), drove electric cars.

Besides transportation, renewable energy storage technologies drive materials research efforts. The transient nature of renewable energy “jerks the grid around,” he says. “If you do that too much, the grid blacks out and nobody likes that.” Telecommunications providers and facilities like hospitals cannot afford to be without power and comprise a market for uninterrupted power supply systems. Bray outlined materials requirements for next-generation capacitors, solid oxide fuel cells, and batteries that are needed to meet energy storage needs.

On the topic of power electronics, Bray discussed semiconductors, thermal management, photovoltaics, white organic LEDs, microelectromechanical systems, and superconductors. Thermal management, he says, is a field with “lots of opportunities and they are never going to end.” That is, once device designers optimize device performance for one set of parameters, they will start looking for the next increment of improvement, which will certainly bring them back around for another improvement in heat management.

Bray noted that processing is a key consideration—and sometimes the deciding factor in whether a material is selected for an application—and cited high-temperature oxide  superconductors as an example. For example, today’s MRI instruments use NbTi superconductors. The material superconducts at liquid helium (4 K) temperatures. Oxide superconductors can be used at liquid nitrogen temperatures (>20 K), but they are so expensive to process, that they are not feasible for commercial products, yet.