Patent ID: 6180503
Filing Date: 2001-01-30
Classification: H01L

Abstract:
A method for forming a laser accessible fuse comprising:(a) providing a silicon wafer having a first insulative layer;(b) depositing a layer of fusible material on said first insulative layer;(c) patterning said layer of fusible material to form a fuse with a rupture zone;(d) depositing a second insulative layer over said wafer;(e) forming conductive contacts to said fuse through openings in said second insulative layer, whereby said rupture zone is connected between, and in electrical series with, at least two of said conductive contacts;(f) depositing a first metal layer on said second insulative layer;(g) patterning said first metal layer to form conductive wiring connected to each of said at least of two conductive contacts, a plate over said rupture zone, and a wiring pad;(h) depositing a third insulative layer over said wafer;(i) patterning said third insulative layer to form a via opening to said wiring pad and a window opening over said rupture zone;(j) depositing a second metal layer on said wafer;(k) depositing an anti-reflective coating on said second metal layer;(l) patterning a bonding pad in said second metal later over said via opening and removing said anti-reflective coating, said second metal layer, and said first metal layer in said window opening;(m) depositing a passivation layer over said wafer; and(n) patterning said passivation layer by anisotropically etching said passivation layer and said anti-reflective coating over said bonding pad while simultaneously etching a region within said window opening, penetrating said second insulative layer to a final second insulative layer thickness over said rupture zone thereby forming a laser access window.