Abstract: A fabricating method of an anti-fuse structure, comprising: providing a substrate having a first conductive plug and a second conductive plug separated from the first conductive plug; forming an amorphous silicon layer on the substrate, wherein a portion of the amorphous silicon layer overlapping the first conductive plug is defined as a first region, and a portion of the amorphous silicon layer overlapping the second conductive plug is defined as a second region; performing an implantation process to the first region and the second region, wherein the first region has a higher doping concentration than the second region; forming a titanium nitride layer on the amorphous silicon layer; and patterning the titanium nitride layer and the amorphous silicon layer.