| 摘要 |
PURPOSE:To make alignment of a contact hole in wiring layers with high precision thereby enabling multilayer wiring structure to be realized in high density by forming stopper layers on the first wiring layer. CONSTITUTION:Stopper layers 15 comprising AlNx or AlOx in high etching selection ratio to an interlayer insulating layer 24 are formed on the first wiring layer. Accordingly, when a contact hole 28 in the second wiring layer is made, the hole is formed in selfalignment using the stopper layers 18 as masks. Through these procedures, even if to some extent rough contact mask pattern is used, the contact hole in the second wiring layer can be aligned with high precision. At the same time, within the contact hole 28 previously made, the first wiring layer and the second wiring layer can be isolated completely by the stopper layers 18 on the upper part and the sides of the first wiring layer as well as the sidewall layers 24a thereby enabling the multilayer wiring structure to be realized with high density. |
