Structure and programming of laser fuse

• US 7,384,824 B2
• Filed: 02/27/2006
• Issued: 06/10/2008
• Est. Priority Date: 11/04/2003
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: International Business Machines Corporation
• Inventors: Muzzy, Christopher D., Lee, Tom C., Wynne, Jean E., Watson, Kimball M., Matusiewicz, Gerald, Li, Baozhen, Badami, Dinesh A., Motsiff, William T.
• Primary Examiner(s): Nadav; Ori
• Application Number:
  US11/362,680
• Publication Number:
  US 20060145291A1
• Time in Patent Office: 834 Days
• Field of Search: 438/132, 438/215, 438/281, 438/333, 438/467, 257/529
• US Class Current: 438/132
• CPC Class Codes: H01L 23/525 with adaptable interconnections
• CPC Class Codes: H01L 23/5254 the change of state resulting from the use of an external beam, e.g. laser beam or ion beam
• CPC Class Codes: H01L 23/5258 the change of state resulting from the use of an external beam, e.g. laser beam or ion beam
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method and structure for fabricating a laser fuse and a method for programming the laser fuse. The laser fuse includes a dielectric layer having two vias filled with a first self-passivated electrically conducting material. A fuse link is on top of the dielectric layer. The fuse link electrically connects the two vias and includes a second material having a characteristic of changing its electrical resistance after being exposed to a laser beam. Two mesas are over the fuse link and directly over the two vias. The two mesas each include a third self-passivated electrically conducting material. The laser fuse is programmed by directing a laser beam to the fuse link. The laser beam is controlled such that, in response to the impact of the laser beam upon the fuse link, the electrical resistance of the fuse link changes but the fuse link is not blown off. Such electrical resistance change is sensed and converted to digital signal.

Claims

1. A method for forming an electronic structure, comprising the steps of:

providing a dielectric layer;

forming a first via and a second via in the dielectric layer;

filling the first and second vias with a first self-passivated electrically conducting material;

forming a fuse link layer on top of the dielectric layer, the fuse link layer comprising a second material having a characteristic of changing its electrical resistance after being exposed to a laser beam;

forming a mesa layer on top of the fuse link layer, the mesa layer comprising a third self-passivated electrically conducting material; and

forming (i) a fuse link from the fuse link layer and (ii) a first mesa and a second mesa from the mesa layer,

wherein the fuse link electrically connects the first and second filled vias,

wherein the first and second mesas are directly above the fuse link and directly above the first and second vias, respectively,

wherein the fuse link is disposed between the first mesa and the dielectric layer, and

wherein the fuse link is disposed between the second mesa and the dielectric layer.

2. The method of claim 1, wherein the second material comprises a substance selected from the group consisting of TaN, TiN, and WN.

3. The method of claim 1, wherein the first self-passivated electrically conducting material comprises a substance selected from the group consisting of Al and W.

4. The method of claim 1, wherein the third self-passivated electrically conducting material comprises a substance selected from the group consisting of Al and W.

5. The method of claim 1, further comprising the step of exposing the fuse link to an ambient atmosphere after the fuse link is formed.