Patent US5198884A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5198884A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor devices having a double-layer interconnection structure

Assignee: Panasonic Holdings Corp
•
Filing: 1991-03-27
•
Granted: 1993-03-30
•
Expires: 2011-03-27
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A semiconductor device having a double-layer interconnection with contact portions between first and second metal films covered with at least a silicon nitride film is provided wherein an electromigration characteristic at the contact portions is improved. The improvement is achieved by defining a value obtained by multiplying a thickness of the silicon nitride film by a stress of the nitride film formed at the contact portions is not larger than 2/5 of a value obtained by multiplying a thickness of the silicon nitride film by a stress of the nitride film formed at non-contact portions. By this, the stress exerted on the second metal film is reduced to improve the electromigration life at the contact portions by about one order of magnitude. The first and second metal films are made of Al or Al-based alloys.

Inventors

  • 👤 Kohsaku Yano
  • 👤 Tetsuya Ueda
  • 👤 Teruhito Ohnishi
  • 👤 Hiroshi Nishimura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 02:29
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/41; H10W20/42; H10W20/45; H10W20/48

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 141 words
In a semiconductor device of the type which comprises a first metal film formed on a semiconductor substrate, an insulating film having openings and formed on the first metal film, a second metal film provided in electric contact with the first metal film through the openings of the insulating film, and a protective layer made of a phosphosilicate glass film and silicon nitride film formed on the second metal film, the improvement in that a value obtained by multiplying a thickness of the silicon nitride film formed on the second metal film layer at the openings by a stress of the film is not larger than 2/5 of a value of a thickness of the silicon nitride film formed on the second metal film on portions other than the openings by a stress of the silicon nitride film on the portions.
Claim 2
Dependent Claim 141 words
In a semiconductor device of the type which comprises a first metal film formed on a semiconductor substrate, an insulating film having openings and formed on the first metal film, a second metal film provided in electric contact with the first metal film through the openings of the insulating film, and a protective layer made of a phosphosilicate glass film and silicon nitride film formed on the second metal film, the improvement in that a value obtained by multiplying a thickness of the silicon nitride film formed on the second metal film layer at the openings by a stress of the film is not larger than 2/5 of a value of a thickness of the silicon nitride film formed on the second metal film on portions other than the openings by a stress of the silicon nitride film on the portions.
Claim 3
Dependent Claim 18 words
The semiconductor device according to claim 1, wherein the first-mentioned value is not less than 6×10 4 dynes/cm.
Claim 4
Dependent Claim 13 words
The semiconductor device according to claim 1, wherein the openings are each tapered.
Claim 5
Dependent Claim 43 words
The semiconductor device according to claim 1, wherein the first and second metal films are each made of a metal selected from the group consisting of Al and Al alloys containing at least one alloying element selected from Si, Ti, Pd and Cu.
Claim 6
Dependent Claim 12 words
The semiconductor device according to claim 4, wherein the metal is Al.
Claim 7
Dependent Claim 21 words
The semiconductor device according to claim 4, wherein the metal is an Al alloy containing the at least one alloying element.
Claim 8
Dependent Claim 22 words
The semiconductor device according to claim 6, wherein the content of alloying element in the alloy ranges up to 5 wt %.

References Cited (Backward Citations)

US5060050A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-03-29 1996-09-28 1997-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-03-29 2000-09-28 2001-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-03-29 2004-09-28 2005-03-30 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag