Paper transistor Could offer alternative to silicon
“The problem with silicon is that it is toxic and fragile,” Kim Jaehwan PhysOrg.com. “An increase in polymer transistors can solve the problem of fragility, but many of these polymers are also toxic to humans and may also produce a large amount of pollution in their manufacture.”
Kim is a scientist at the University of INHA in South Korea. Along with Sungryul Yun, Sang-Dong Jang, Gyu-Young Yun and Joo-Hyung Kim, Kim has been studying how to develop a transistor that is more environmentally friendly and meets the requirements of flexibility and ease of use in the advancement of electronic devices. “What we found,” he says, “is that it is possible to make a transistor of a special kind of paper pulp.” The results of the team’s efforts are available in Applied Physics Letters: “The paper made with transistors covalently multiwall carbon nanotubes and cellulose.”
“This paper pulp is flexible and more environmentally friendly,” explains Kim. “We changed the cellulose paper that has the properties of a transistor. Nanontube We have added carbon to improve electrical properties of cellulose, since a transistor must be a semiconductor. We invented the transistor, tasted it and found that worked. ”
The South Korean team had to deposit the electrodes on the top and the bottom of the transistor to produce the appropriate electric field. “This is a very unique property,” Kim says. “This is a challenge of technology, placing electrodes and cables in this document, and the use of nanotubes as part of the transistor. You can see why there are challenges ahead for the full implementation of this.”
Although this is a good first step, Kim realizes that there is still much to be done before mass production of this type of transistor can move forward. “First, we must understand why this material offers an interesting phenomenon. They will also improve performance. While the works, the transistor can do better, and we must work on improving it.”
He continues: “We have to study the mechanics of the document and find out how it can be mass produced. Our laboratory can not start mass production, and we’re going to have to develop a system that can capture the only process required to make these transistors .
However, Kim is hoping that the answers can be found. “We’ve been working on this for about six years, and we are pleased with progress so far. Although this technology is not fully available to us immediately, we are still taking the first steps to make the transistors that are flexible, biocompatible and more environmentally sustainable. “
• Visit CRI EAPap from INHA University.
• Sungryul Yun, et. al., “Paper transistor made with covalently bonded multiwalled carbon nanotube and cellulose,” Applied Physics Letters (2009). Available online: http://link.aip.org/link/?APPLAB/95/104102/1.