Issue link: https://iconnect007.uberflip.com/i/978458
MAY 2018 I PCB007 MAGAZINE 27 Shaughnessy: John, is there anything you'd like to add? Hendricks: I would just say that everything I've heard has been correct. The millimeter wave does present a lot of challenges, purely from the RF point of view, as has been pointed out. Millimeter wave is nothing new. Not even any- thing new in consumer applications because you'll see millions of 77-gigahertz radars be- ing produced every year for the automotive industry now, and things like adaptive cruise control. So, from the RF point of view, it's not such a huge challenge. But people are develop- ing new modulation technologies and all kinds of stuff that go with that, which is complete- ly new. From the PCB side of things, it's the com- plexity of the boards at those frequencies that's rather new. Even the 77-gigahertz radar is a relatively simple PCB, compared to some of the designs we are starting to see coming along in 5G. The only other thing that I would point out is when we talk about sub-six gigahertz versus millimeter wave; it's going to be a long time before the millimeter wave really grows that quickly. The initial applications look more like fixed broadband access, and people are work- ing on mobile applications at millimeter wave, so that is a lot more challenging. In the ini- tial, let's say, five-year period, the vast majori- ty of 5G designs are not going to be millimeter wave, at least in terms of production volumes. They're going to be down below six gigahertz. Shaughnessy: Sounds like pretty interesting stuff. It sounds like it's going to make some little disruption, every step of the way. More change. Hendricks: It's the one thing that never chang- es. Shaughnessy: Well, I appreciate all of you join- ing us for this talk. I know you're all busy. Jordan: You too, Andy. Thank you. PCB007 One-Dimensional Material Packs a Powerful Punch for Next Generation Electronics Engineers at the University of California, Riverside, have demonstrated prototype devices made of an exotic material that can conduct a current density 50 times greater than conventional copper intercon- nect technology. As transistors in integrated circuits become small- er and smaller, they need higher and higher current densities to perform at the desired level. Most con- ventional electrical conductors, such as copper, tend to break due to overheating or other factors at high current densities. The advent of graphene resulted in a massive, worldwide effort directed at investigation of other two-dimensional, or 2D, layered materials that would meet the need for nanoscale electronic components that can sustain a high-current density. 2D materials consist of a single layer of atoms, while 1D materials consist of individual chains of atoms. One can think of 2D materials as thin slices of bread while 1D materials are like spaghetti. Compared to 1D materials, 2D materials seem huge. A group of researchers led by Alexander A. Balandin, a distinguished professor of electrical and computer engineering in the Marlan and Rosemary Bourns Col- lege of Engineering at UC Riverside, discovered that zirconium tritelluride, or ZrTe3, nanoribbons have an exceptionally high current density that far exceeds that of any conventional metals like copper. The new strategy undertaken by the UC Riverside team pushes research from two-dimensional to one- dimensional materials—an important advance for the future generation of electronics.