Patent ID: 6627969
Filing Date: 2003-09-30
Classification: H01L

Abstract:
An antifuse structure, comprising:a conductive plug disposed in an opening in a dielectric layer; a programmable material layer feature disposed over a top surface of the conductive plug, the programmable material comprising amorphous silicon, the programmable material layer having a lateral edge; a first barrier metal layer disposed over the programmable material layer feature and extending beyond the lateral edge of the programmable material, wherein at least a portion of the first barrier metal layer is disposed over the dielectric layer without having the programmable material layer disposed between the first barrier metal layer and the dielectric layer, the first barrier metal layer having a top surface; a second barrier metal layer disposed over the top surface of the first barrier metal layer, wherein the barrier metal of the first barrier metal layer at the top surface of the first barrier metal layer has a higher concentration of at least one of oxygen and nitrogen than the barrier metal of the second barrier metal layer at the bottom surface of the second barrier metal layer; and a metal layer comprising one of aluminum and copper, the metal layer comprising one of aluminum and copper being disposed over and directly contacting the second barrier metal layer.