摘要 |
Method for forming dual damascene etch structures in wafers, and semiconductor devices formed according to the method. The present invention utilizes the two-step etch process to form dual damascene structures in organosilicate dielectric layers. According to one embodiment of the present invention, a first etch step is undertaken utilizing a first, low selectivity etchant, which etches completely through the trench dielectric and almost completely through the via dielectric, leaving a small remainder of the via dielectric over the barrier layer protecting metalized objects protected by the barrier layer. After the first etch step, a second etch step is performed utilizing a second, highly selective etchant. This second etch step is conducted with little damage to the barrier layer.An alternative embodiment of the present invention contemplates a "trench-first" etch strategy. |