The National Research Foundation of Korea announced on April 13 that a research team led by professor Ham Moon-ho at the Gwangju Institute of Science and Technology developed an oxide thin film transistor production technique utilizing lithium instead of a more expensive rare earth element.
At present, the production of large display screens in which electrons flow quickly without loss requires indium doping. Indium, which is an expensive rare earth element, tends to be entangled in the solution, which has hindered the commercialization of oxide thin film transistors.
The research team dealt with this problem by replacing indium with lithium. In addition, it utilized acid treatment so that lithium can be better mixed with the raw material solution. In most cases, thin film transistors are produced by the solution containing various raw materials being injected onto semiconductor substrates.
According to the research team, the charge transfer rate of an oxide thin film transistor employing its technique is 20 times and five times those of a zinc oxide thin film transistor and a lithium-added zinc oxide thin film transistor, respectively. “We are expecting that this oxide thin film transistor will have a variety of applications with regard to the production of flexible display panels, transparent display panels and the like,” the professor explained.