Researchers at the University of Illinois Urbana-Champaign have developed a semiconductor device made using diamond, that has the highest breakdown voltage and lowest leakage current compared to previously reported diamond devices. Such a device will enable more efficient technologies needed as the world transitions to renewable energies.<\/p>\n
According to a new report from the National Academies of Sciences, Engineering, and Medicine, \u201cPerhaps the single greatest technological danger to a successful energy transition is the risk that the nation fails to site, modernize, and build out the electrical grid. Without increased transmission capacity, renewables deployment would be delayed, and the net result could be at least a temporary increase in fossil fuel emissions, preventing the nation from achieving its emission reduction goals.\u201d<\/p>\n
\u201cTo meet those electricity demands and modernize the electrical grid, it’s very important that we move away from conventional materials, like silicon, to the new materials that we are seeing being adopted today like silicon carbide and the next generation of semiconductors\u2014ultra-wide bandgap materials\u2014such as aluminum nitride, diamond and related compounds,\u201d says electrical and computer engineering professor Can Bayram, who led this research, published in the journal IEEE Electron Device Letter<\/em>s.<\/p>\n Most semiconductors are built using silicon and thus far, have met society’s electrical needs. But as Bayram points out, \u201cWe want to make sure that we have enough resources for everyone, while our needs are evolving. Right now, we are using more and more bandwidth, we are creating more data (that also comes with more storage), and we are using more power, more electricity and more energy in general. The question is: is there a way we can make all of this more efficient, rather than generating more energy and building more power plants?\u201d<\/p>\n Diamond is an ultra-wide gap semiconductor with the highest thermal conductivity, which is the ability of a material to transfer heat. Due to these properties, diamond semiconductor devices can operate at much higher voltages and currents (with less material) and will still dissipate the heat without causing a reduction in electrical performance, compared to traditional semiconductor materials like silicon.<\/p>\n \u201cTo have an electricity grid where you need high current and high voltage, which makes everything more efficient for applications such as solar panels and wind turbines, then we need a technology that has no thermal limit. That’s where diamond comes in,\u201d Bayram says.<\/p>\n Diamond can be made affordably and sustainably in the lab, making it a viable and important semiconductor alternative. Natural diamond is formed deep below Earth’s surface under immense pressure and heat, but since it is essentially just carbon\u2014of which there is an abundance of\u2014artificially synthesized diamond can be made in weeks rather than billions of years, while also producing 100 times less carbon emissions.<\/p>\n In this work, Bayram’s team shows that their diamond device can sustain high voltage, approximately 5 kV, although the voltage was limited by setup of measurement and not from the device itself. In theory, the device can sustain up to 9 kV. This is the highest voltage reported for a diamond device. Besides the highest breakdown voltage, the device also demonstrates the lowest leakage current, which can be thought of like a leaking faucet but with energy. Leakage current affects the overall efficiency and reliability of the device.<\/p>\n The team built an electronic device better suited for high power, high voltage applications for the future electric grid and other power applications on an ultra-wide band gap material, synthetic diamond, which promises better efficiency and better performance than current generation devices. Hopefully, the team will continue optimizing this device and other configurations to approach the performance limits of diamond’s material potential.<\/p>\n <\/p>\n