Back-channel-etched thin-film transistor using c-axis-aligned crystal In–Ga–Zn oxide

Our crystalline In–Ga–Zn oxide (IGZO) thin film has a c-axis-aligned crystal (CAAC) structure and maintains crystallinity even on an amorphous base layer. Although the crystal has c-axis alignment, its a-axis and b-axis have random arrangement; moreover, a clear grain boundary is not observed. We fabricated a back-channel-etched thin-film transistor (TFT) using the CAAC-IGZO film. Using the CAAC-IGZO film, more stable TFT characteristics, even with a short channel length, can be obtained, and the instability of the back channel, which is one of the biggest problems of IGZO TFTs, is solved. As a result, we improved the process of manufacturing back-channel-etched TFTs.