Electrical Conduction across the Direct Contact between Indium–Tin Oxide and Al–Ni Alloy Layers

Abstract

The electrical conduction across direct contacts between indium–tin oxide (ITO) and the newly developed Al–Ni alloys, used for amorphous silicon thin-film transistors (a-Si TFTs) in liquid crystal displays (LCDs), has been studied. The ITO/Al–Ni alloy interfaces were examined by both electrical measurements using nanoprobes and cross-sectional transmission electron microscopy (XTEM). It was found that the major conduction path across the ITO/Al–Ni alloy interface was via Al3Ni precipitates, and that the resistivity of the ITO/Al–Ni alloy contact strongly depended on the conditions of the Al–Ni alloy surface. It was thus concluded that the generation of non-oxidized Al3Ni precipitates after photoresist stripping is important for high-quality direct contacts. The present results on the Al–Ni alloy compositions and ITO/Al–Ni alloy interfaces have already been considered in the actual production of a-Si TFTs for LCDs.