Programmable fuse and anti-fuse elements and methods of changing conduction states of same

摘要

A programmable anti-fuse element includes a substrate (224), an N-well (426) in the substrate, an electrically insulating layer (427) over the N-well, and a gate electrode (430) over the electrically insulating layer. The gate electrode has n-type doping so that the N-well is able to substantially contain within its boundaries a current generated following a programming event of the programmable anti-fuse element. In the same or another embodiment, a twice-programmable fuse element (100) includes a metal gate fuse (110) and an oxide anti-fuse (120) such as the programmable anti-fuse element just described.