Performance enhancement in oxide thin-film transistors and memory devices

Abstract

In this study, we present performance enhancement in amorphous oxide semiconductor (AOS) thin-film transistors and memory devices. By improving the performance of oxide transistors, it could be used as a various application technology for ultrahigh resolution display backplane, high speed operation circuit and memory devices application. We developed a high-mobility back channel etch (BCE) Al-In-Zn-Sn-O/In-Zn-O (AIZTO/IZO) double-layer channel thin-film transistors. The field-effect mobility of 53.2 $cm^2$/Vs was obtained with thin IZO-inserted double-layer channel TFT. The positive bias stability was also improved. We fabricated ring oscillators, which exhibited oscillating frequency of 296 kHz. For the application of oxide transistors, nonvolatile memories have been developed using oxide TFTs. Based on the BCE structure, we have fabricated a non-volatile memory with charge storage layer inserted between $SiO_2$ insulators. The proposed body-contacted memory structure improved memory erase speed, which is the most important issue in oxide memory TFTs. These results will be a cornerstone in developing novel applications for next-generation display and wearable devices.