In another addition to the long list of advantages of graphene for nanotech applications, researchers at Columbia University have demonstrated that it is the strongest known material. From “Strongest Material Ever Tested“, at Technology Review, written by Katherine Bourzac (credit KurzweilAInet):
Materials scientists have been singing graphene’s praises since it was first isolated in 2005. The one-atom-thick sheets of carbon conduct electrons better than silicon and have been made into fast, low-power transistors. Now, for the first time, researchers have measured the intrinsic strength of graphene, and they’ve confirmed it to be the strongest material ever tested. The finding provides good evidence that graphene transistors could take the heat in future ultrafast microprocessors.
Jeffrey Kysar and James Hone, mechanical-engineering professors at Columbia University, tested graphene’s strength at the atomic level by measuring the force that it took to break it. They carved one-micrometer-wide holes into a silicon wafer, placed a perfect sample of graphene over each hole, and then indented the graphene with a sharp probe made of diamond. Such measurements had never been taken before because they must be performed on perfect samples of graphene, with no tears or missing atoms, say Kysar and Hone.
…the measurements are yet another demonstration of the remarkable properties of graphene. “We knew graphene was the strongest material; this work confirms it,” says Konstantin Novoselov, a fellow at the University of Manchester, who was the first to isolate two-dimensional sheets of the material.
The material’s strength is particularly good news for those in the semiconductor industry who hope to make computers faster by developing microprocessors that use graphene transistors. “The main liability concerning the microprocessing industry is strain,” says Julia Greer, a materials scientist at Caltech. Not only must the materials used to make transistors have good electrical properties, but they must also be able to survive the stresses of manufacturing processes and the heat generated by repeated operations. The processes used to pattern metal electrical connections onto microprocessors, for example, exert stresses that can cause chips to fail. And, says Greer, the main obstacle to making faster microprocessors is that “the heat is too much for materials to take.” Based on measurements of its strength, graphene transistors could take the heat.
The research was published in Science [abstract].
—Jim
