Process development of inverted-staggered amorphous InGaZnO thin-film transistors with wet-etched electrodes

摘要

Process development of inverted-staggered amorphous InGaZnO thin-film transistors (a-IGZO TFTs) with wet-etched electrodes was employed in this paper. Five metals (Al, Cu, Ti, Ta, and Cr) as well as various etchants were comparatively investigated, indicating H_2O_2 based solution etched Ta films were good candidates for the wet-etched electrodes of a-IGZO TFTs. The aforementioned findings along with other improving attempts successfully established inexpensive processing steps and conditions with which stable a-IGZO TFTs were finally fabricated. The device performance was reasonably good enough (μ_(FE) of 6.0cm~2/V·s, V_(th) of 2.5V, SS of 1.8V/decade, and l_(on)/l_(off) of 10~6) to meet the requirements of applications especially for small-sized flat panel displays.