Organic Thin-Film Transistors Made with Speeds Comparable to Silicon Circuits
While silicon has served us well for decades in our electronics, the future may be dominated by carbon instead. One of the reasons for the change is that carbon-based electronics can be transparent and even flexible, but sadly those that have been built are slower than their inorganic counterparts. Researchers at Stanford School of Engineering however have developed a new method to produce carbon-based, thin-film transistors that returns transistors with carrier mobility comparable to that of modern polysilicon materials.
The key to what the researchers did was changing how the thin film was produced. Typically a solution of carbon-rich molecules and a complementary plastic is dropped onto a spinning platter, covering the intended substrate. The researchers decided to spin the platter at a high speed and kept the drop in a smaller area, about the size of a postage stamp. The result was a higher concentration of organic molecules in the thin film, and greater alignment among them. This increased the carrier mobility of the molecules, which is a measure of how quickly electrons can move through a material.
At present this research is still experimental, so we cannot expect to see such high-speed organic transistors replacing equally-fast silicon ones soon. As the method is further refined over time though, we could see the speeds of these transistors increase further.
Source: Stanford School of Engineering