Semiconductor device and semiconductor device fabrication method
A multilayer wiring in a semiconductor device includes a first lower wiring formed in a first insulating layer, a via which is formed in a second insulating layer over the first insulating layer and which is connected to the first lower wiring, and an upper wiring connected to the via. The upper wiring has an outer edge at which a nick portion is formed beside a portion of the upper wiring to which the via is connected. The formation of the nick portion at the outer edge of the upper wiring prevents the via from enlarging.
1. A semiconductor device fabrication method comprising:
forming a first insulating layer;
forming a first wiring and a second wiring separated from the first wiring in the first insulating layer;
forming a second insulating layer over the first insulating layer;
forming in the second insulating layer a via hole that reaches the first wiring;
forming in the second insulating layer a trench that is connected to the via hole and that includes an outer edge at which a first nick portion is formed beside the via hole and that overlaps with the first wiring and a first part of the second wiring in a plan view; and
forming a conductive material in the via hole and the trench to form a via and a third wiring connected to the first wiring.