Fabrication and laser deletion of microfuses
US5374590A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1993 |
| Grant date | Dec 20, 1994 |
| Priority date | — |
| Expiry date | Apr 28, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of fabricating a microfuse, deletable by laser pulses utilizes laser pulses of a predetermined spot diameter and beam alignment accuracy. A fusible link forming a portion of the microfuse is defined such that its length is at least equal to the sum of the laser spot diameter and the beam alignment accuracy and its width is no greater than half the laser spot diameter. A method of deleting the microfuse by laser pulses is provided where the microfuse has a predetermined composition, length and width having an axis bisecting the width and parallel to the length and is covered with a passivation layer at least 3 .mu.m thick. The method includes adjusting the diameter of the beam of laser light (i) to at least a minimum diameter of W+.DELTA.P.sub.w, where W equals the width of the microfuse fuse link and .DELTA. P.sub.w equals the accuracy of the beam in the direction of W and (ii) to no more than a maximum diameter of L+.DELTA.P.sub.L, where L equals the length of the microfuse fuse link and .DELTA.P.sub.L equals the accuracy of the beam in the direction of L.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.