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Airdate: Sep 16, 2020
Scientist: Sean Muir

Electric Sandwich

Electric Sandwich
The technology behind your computer screen is, in effect, a layered electronic "sandwich".

Sustainable Chemistry Electric SandwichMusic; Ambience: Atomic layer deposition system - vacuum releaseJM: I used to think of electricity as something that happens through a wire circuit. But in the world of computer chips and display monitors, electricity flows through thin layers of material. How thin? Down to layers of atoms. I'm Jim Metzner and this is the Pulse of the Planet.JM: We're in a laboratory at Oregon State University, with Sean Muir, a former graduate research fellow.SM: And we use this system for laying down ultra-thin layers of various materials. The reason we would like to have ultra-thin layers of various materials is because in a lot of devices we ultimately need to enable to control how the electrons move through the device. So, the atomic layer deposition system can be used to lay down materials that are called semiconductors or other materials that are called metals. JM: I think of these layers of materials as ultra thin electronic sandwiches.SM: Any sandwich requires first a base layer of bread in this case we're gonna use a conductive material such as a metal. In the middle we're gonna have an insulating layer. On top of that we have another conductive layer. By using the system we can deposit insulating or semiconducting layers in between two conducting layers. Ultimately this sandwich makes a thin film diode device.JM: And just to give you a sense of the scale of these layers.SM: We're depositing layers that are on the order of 10 to 50 nanometers thick and so this is the range of most viruses as far as size. JM: Our thanks to the Center for Sustainable Materials Chemistry. Pulse of the Planet is made possible by the National Science Foundation. I'm Jim Metzner.