"We have demonstrated a principle that no one else has done before. Certainly, the wooden transistor is slow and clumsy, but it works and the development potential is great," Isak Engquist, assistant professor at the Laboratory of Organic Electronics at Linkoping University, said in a statement.
Transistors were invented nearly a hundred years ago, and are seen as an important milestone in technological development, on par with the telephone and the light bulb. Today, they are a key component in modern electronics and are manufactured down to the nanoscale. A transistor regulates the current that passes through it and can also function as a switch.Previous attempts to make transistors out of wood have only been able to regulate ion flux and stopped working when the ions ran out. The new development, on the other hand, can function continuously at a selected output signal level. It can also turn the power on and off, albeit quite slowly – “off” took about a second and “on” about five seconds.The transistor was created from balsa wood, which was chosen for its even structure and lack of annual rings. Then the researchers removed the lignin, an organic polymer that forms structural material in support tissues, and all that remained were long cellulose fibers with channels where the lignin had previously been. The final cellulose-based structure was coated with a conducting polymer.