Electronic device and method for fabricating the same
An electronic device has an element formed in the chip region of a substrate, a plurality of interlayer insulating films formed on the substrate, a wire formed in the interlayer insulating films in the chip region, and a plug formed in the interlayer insulating films in the chip region and connecting to the wire. A seal ring extending through the plurality of interlayer insulating films and continuously surrounding the chip region is formed in the peripheral portion of the chip region. A stress absorbing wall extending through the plurality of interlayer insulating films and discretely surrounding the seal ring is formed outside the seal ring.
1. An electronic device comprising:
a substrate;
a multilayer structure composed of a plurality of interlayer insulating films formed on the substrate;
a seal ring structure formed to contact the substrate, to extend through the multilayer structure which is located in a peripheral portion of a chip region and to continuously surround the chip region; and
stress absorbing walls in a double or higher-order multiple structure formed to extend through the multilayer structure which are located outside the seal ring structure viewed from the chip region and to discretely surround the entirety of the seal ring structure in a plan view,
wherein each of components of one of the stress absorbing walls in the double or higher-order multiple structure which is formed at a position most distant from the seal ring structure has a shorter length along a direction in which the seal ring structure extends than each of components of the other stress absorbing wall or walls.
2. The electronic device of claim 1 , wherein gap portions between respective discrete portions of each of the stress absorbing walls in the double or higher-order multiple structure are not aligned in rows.
3. The electronic device of claim 1 , wherein each of the seal ring structure and one of the stress absorbing walls is composed of at least one of W, Al, and Cu.
4. The electronic device of claim 1 , wherein:
a piece of one of the stress absorbing walls has a substantially rectangular shape having a long side and a short side which is shorter than the long side, and
the long side of the stress absorbing wall is provided in a direction parallel to one side of the seal ring structure.
5. The electronic device of claim 1 , wherein the seal ring structure has a substantially planar shape with a winding in a portion corresponding to one side of the chip region.
6. The electronic device of claim 1 , wherein the seal ring structure has a substantially planar shape with a projection extending to the opposite side of the chip region in a portion corresponding to one side of the chip region.
7. The electronic device of claim 1 , wherein the seal ring structure is in a double or higher-order multiple configuration.
8. The electronic device of claim 1 , wherein:
a piece of at least one of the stress absorbing walls has a substantially rectangular shape having a long side and a short side which is shorter than the long side, and
a length of the long side is longer than a distance between said piece and another piece adjacent to said piece.
9. The electronic device of claim 1 , wherein the stress absorbing walls are located outside the seal ring structure but are not located inside the seal ring structure viewed from the chip region.