Semiconductor wafer and its manufacture method, and semiconductor chip
A semiconductor wafer includes: a first semiconductor chip area formed with a semiconductor element; a second semiconductor chip area formed with a semiconductor element; and a scribe area sandwiched between the first and second semiconductor chip areas; wherein: the first semiconductor chip area includes a first metal ring surrounding the semiconductor element formed in the first semiconductor chip area; and the metal ring is constituted of a plurality of metal layers including a lower metal layer and an upper metal layer superposed upon the lower metal layer, and the upper metal layer is superposed upon the lower metal layer in such a manner that an outer side wall of the upper metal layer is flush with the outer side wall of the lower metal layer or is at an inner position of the first semiconductor chip area relative to the outer side wall of the lower metal layer.
1. A semiconductor device comprising:
a semiconductor substrate including a first semiconductor chip area formed with a semiconductor element;
laminated interlayer insulating films formed on said substrate;
a first metal ring formed in said laminated interlayer insulating films of said first semiconductor chip area, formed in a loop shape, and surrounding said semiconductor element;
an opening formed in said laminated interlayer insulating films and exposing a part of a first side wall and an upper surface of said first metal ring; and
a second metal ring formed on said semiconductor substrate and surrounding said first metal ring, an upper surface of said second metal ring being lower than said upper surface of said first metal ring.
2. The semiconductor device according to claim 1 , wherein:
said opening exposes a first part of an outer side wall of said first metal ring; and
a second part of said outer side wall of said first metal ring is covered by said laminated interlayer insulating films.
3. The semiconductor device according to claim 1 , further comprising a lower insulating film disposed lower than said first metal ring in a height direction, wherein an outer end of said lower insulating film is disposed outer relative to an outer end of a lowermost metal layer of said first metal ring.
4. The semiconductor device according to claim 1 , wherein said opening exposes said upper surface of said second metal ring.
5. The semiconductor device according to claim 1 wherein:
said semiconductor substrate has a first conductivity type; and
a lowermost metal layer of said first metal ring is formed on a semiconductor region of said semiconductor substrate into which impurities of said first conductivity type are implanted.
6. The semiconductor device according to claim 1 , wherein:
said first metal ring includes a first lower metal layer and a first upper metal layer formed directly on said first lower metal layer; and
said first lower metal layer and said first upper metal layer contain copper and are formed by dual damascene.
7. The semiconductor device according to claim 1 wherein:
said first metal ring includes a first lower metal layer and a first upper metal layer formed directly on said first lower metal layer;
said second metal ring includes a second lower metal layer and a second upper metal layer formed directly on said second lower metal layer;
an outer side wall of said first lower metal layer is nearer from a border of said first semiconductor chip area than an outer side wall of said first upper metal layer; and
an outer side wall of said second lower metal layer is nearer from said first metal ring than an outer side wall of said second upper metal layer.
8. The semiconductor device according to claim 1 wherein an outer side wall of said first metal ring is smooth.