Investigation of link formation in a novel planar-type antifuse structure

Abstract

A novel antifuse structure with planar-type polysilican pad is described. The formation of a link between the aluminum electrodes after application of a programming voltage was also investigated. The structure consists of Al/SiOJpoly-Si/SiOa/AI layers. The poly-Si pad was doped with boron and the thickness of the antifuse dielectric was 9 rim. When a programming voltage is applied, the electrodes are connoted by the mass transfer of aluminum through the dielectric and the doped polysilican pad. The an-state resistance of about 10 ~, which is the lowest an-state resistance ever reported, is obtained after breakdown with 9.9 V programming voltage. Scanning Auger microscopy analyses show the propagation of a link, as mass transfer of aluminum in the boron doped polysilicon pad. The elliptical link has a maximum diameter of 1.0 I~m in the horizontal direction and a minimum diameter of 320 nm in the vertical direction.