Click for the transcript of Plastic Electronics: Inventing the Future.
Plastic electronics are electronic devices in which the active components are made out of carbon-based materials. So these are plastics, or polymers, or small molecules and the reason you want to make plastic electronics is because you want to make use of the attributes of these plastic materials. These include their mechanical flexibility, they're lightweight, they can be produced with tunable properties, and this is something you can't easily do with inorganic materials. My name is Yu Lin Lieu and I work in the field of plastic electronics.
In the field of plastic electronics, it all starts with chemistry. We need to make or synthesize new materials that are conductive or semiconductive, so they have the electrical properties that we would like so that when we incorporate them into electronic devices they're active. So in our group, some of the researchers make new materials, some of the researchers characterize the structures are these materials, and some other incorporate these materials to understand their potential in applications like transistors and solar cells.
Polyaniline is a conducting polymer that changes color. In here, this color change is triggered by applying a voltage to the sample. So the potential applications for polyaniline, in addition to being electrodes, we can use it as electrochromic displays, as well as sensors that change color when exposed to a specific chemical or reagent.
We use a process called spin coating to make thin layers of these compounds. The layers end up to be about a hundred nanometers thick that's about a thousand times thinner than my hair.
Here we examine the films we make under the microscope to see how the crystals grow during spin coating. We try to control the size of the crystals in the film. The bigger the crystals, the better the devices will turn out.
To make devices, we have to make electrical contact to the film by evaporating gold. Gold is evaporated through a mask. The pattern of the mask determines where gold is cooled. After the placement of a mask, we put the sample in the gold evaporator. Alternatively, we can evaporate gold electrodes on a clear silicone rubber-stamp, and laminate the rubber stamp onto the polymer film to make our devices. The structure of the devices depends on their function. In my opinion, their beauty derives from their functionality. Compared to inorganics like silicon, classics had unique attributes which include their lightweightness and their mechanical flexibility, their potential in their tunability in terms of their properties and soon to incorporate all these attributes into electronic devices would be really nice.
Well, the field's really exciting because it's a young field and it's growing and it's directly tied to applications that can have direct implications on the quality of our lives. Imagine electronic wallpaper that changes patterns from green stripes to pink polka dots at a click of a switch. Imagine tinted windows that can also generate power during the day. Imagine disposable sensors that would change color if the water sources contaminated or yet think of smart plastic patches that can monitor your health and deliver medication when you're sick. The possibilities are endless.