Fuse structure

A fuse window having a plurality of fuse structures, each of the fuse structures comprising:

• an optimal position of laser spot defined above a substrate;
• a first conductive layer is formed on part of the substrate;
• a first dielectric layer is formed on the substrate and the first conductive layer;
• a second conductive layer is formed on the first dielectric layer;
• a second dielectric layer is formed on the first dielectric layer and the second conductive layer;
• a third conductive layer comprising the position of laser spot is formed on part of the second dielectric layer;
• a plurality of first conductive plugs penetrating the first dielectric layer, to electrically connect the first conductive layer and the second conductive layer;
• and
• at least one second conductive plug penetrating the second dielectric layer, to electrically connect the second conductive layer and the third conductive layer;
• wherein each of the fuse structures has its own position of laser spot on the third conductive layer, and the fuse structures are insulated from one another, and the underside of the laterals of the third conductive layer having the position of laser spot of any the fuse structures corresponds to the second conductive layer of the adjoining fuse structure, and the first conductive layer serves as a backup layer if the second conductive layer is broken.