Make-link programming of semiconductor devices using laser-enhanced thermal breakdown of insulator

• US 4,912,066 A
• Filed: 03/07/1988
• Issued: 03/27/1990
• Est. Priority Date: 07/18/1984
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Wills, Kendall S.
• Primary Examiner(s): Hearn, Brian E.
• Assistant Examiner(s): McAndrews, Kevin
• Application Number:
  US07/164,763
• Time in Patent Office: 750 Days
• Field of Search: 437/19, 437/173, 437/174, 437/922, 437/228, 437/233, 437/225, 437/247, 437/192, 437/193, 148/DIG. 55, 219/121 LG, 219/121 LH, 219/121 LJ, 357/71
• US Class Current: 438/600
• CPC Class Codes: H01L 21/76894 using a laser, e.g. laser cutting, laser direct writing, laser repair
• 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 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
• CPC Class Codes: Y10S 148/055 Fuse

Abstract

A semiconductor device is programmed by a laser beam which causes an insulator between two conductors on a silicon substrate to be permanently altered, as by breakdown of the insulator. The conductors may be metals such as aluminum or tungsten, and the insulator is a layer of deposited or thermal silicon oxide. The breakdown may be enhanced by voltage applied between the conductors while the laser beam is focused on the structure.

Claims

1. A method of making and programming a laser-beam programmable device at a face of a semiconductor body, comprising:

forming a first conductive layer over a portion of said face;

forming a second conductive layer over a portion of said face, said second conductive layer not touching said first conductive layer;

forming an insulating layer over a first target area of said first conductive strip and a second target area of said second conductive strip;

forming a conductive strip over said first and second target areas; and

exposing said first and second target areas to a laser beam, said first and second target areas lying within the area of said laser beam, said insulating layer being altered by the laser beam to create a conductive path from said first conductive layer through said conductive strip to said second conductive layer;

wherein said first and second conductive layers, and said conductive strip, are formed of materials different from one another.