| 摘要 |
PURPOSE:To form good contacts between wiring layers with good yield even in very fine contacts in a semiconductor IC, by using a specific etchant. CONSTITUTION:The addition of a non-ion activator to an etchant made mainly of phosphoric acid is used as the etchant. When this etchant is used, an aluminum oxide film 6 on the first wiring layer 3 can be completely removed because of filling a contact hole 5 with the etchant. This results in good contact of the first layer wiring 3 with the second layer wiring 7. Such a use of an acid etchant with the addition of an acid-resistant non-ion activator which improves wetting without giving bad effects on semiconductor elements allows the etchant to sufficiently infiltrate into and fill contact holes even with diameters 5-1mum, and the remaining oxide film to be completely removed. |
