Fabricating electrical metal fuses without additional masking

摘要

A method of forming an electrical metal fuse comprising the following steps. A substrate is provided. A first patterned dielectric layer is formed over the substrate. The first patterned dielectric layer having at least one first opening exposing at least a portion of the substrate. A first planarized structure is formed within the at least one first opening. A second patterned dielectric layer is formed over the first planarized structure. The second patterned dielectric layer having a second opening exposing at least a portion of the first planarized structure. A second planarized structure is formed within the second opening whereby the first planarized structure and the second planarized structure comprise the electrical metal fuse. The electrical metal fuse having a middle portion, having a thickness and a width, between two end portions each having a thickness and a width. The thickness and width of the middle portion being less than the respective thickness and width of the end portions.