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US4897709A Expired / Lapsed US ⏱️ 0.0 years remaining

Titanium nitride film in contact hole with large aspect ratio

Assignee: Hitachi Ltd
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Filing: 1988-05-26
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Granted: 1990-01-30
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Expires: 2008-05-26
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Abstract

Abstract A semiconductor device includes a titanium nitride film as a barrier which is formed in a hole. The width or diameter of the hole is smaller than 1 μm, and the aspect ratio thereof is larger than 0.7. The sidewall of the hole is substantially perpendicular to the surface of a semiconductor substrate. By the low pressure CVD method with a cold wall type CVD apparatus, it becomes possible to form the titanium nitride film having excellent characteristics with a good step coverage in a considerably fine hole having a large aspect ratio.

Inventors

  • 👤 Natsuki Yokoyama
  • 👤 Yoshio Homma
  • 👤 Kenji Hinode
  • 👤 Kiichiro Mukai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 01:04
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10B; H10B12/00; H10B12/30; H10B12/31; H10W20/056; H10W20/40; H10W20/41; H10W20/425

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 131 words
A semiconductor device comprising: an insulating film, having a surface, formed on a surface of a semiconductor substrate, and having at least a hole whose side wall is substantially perpendicular to said substrate surface; and a titanium nitride film disposed thereon, extending from the surface of said semiconductor substrate, exposed by said hole, along said side wall, and having a portion on the insulating film surface, said titanium nitride film extending along said side wall having a thinnest portion, the portion of the titanium nitride film on the insulating film surface having a film thickness, the thickness of said thinnest portion of said titanium nitride film within said hole, being more than 0.6 times as large as the film thickness of the titanium nitride film portion on said insulating film surface.
Claim 2
Dependent Claim 131 words
A semiconductor device comprising: an insulating film, having a surface, formed on a surface of a semiconductor substrate, and having at least a hole whose side wall is substantially perpendicular to said substrate surface; and a titanium nitride film disposed thereon, extending from the surface of said semiconductor substrate, exposed by said hole, along said side wall, and having a portion on the insulating film surface, said titanium nitride film extending along said side wall having a thinnest portion, the portion of the titanium nitride film on the insulating film surface having a film thickness, the thickness of said thinnest portion of said titanium nitride film within said hole, being more than 0.6 times as large as the film thickness of the titanium nitride film portion on said insulating film surface.
Claim 3
Dependent Claim 158 words
A semiconductor device comprising: an insulating film, having a surface, formed on a surface of a semiconductor substrate, and having at least a hole whose diameter is smaller than 1 μm, the hole having an aspect ratio, the aspect ratio of the hole being greater than 0.7, the hole having a side wall that is substantially perpendicular to said substrate surface; and a titanium nitride film disposed thereon, extending from the surface of said semiconductor substrate, exposed by said hole, along said side wall, and having a portion on the insulating film surface, said titanium nitride film extending along said side wall having a thinnest portion, the portion of the titanium nitride film on the insulating film surface having a film thickness, the thickness of said thinnest portion of said titanium nitride film, within said hole, being more than 0.6 times as large as the film thickness of the titanium nitride film portion on said insulating film surface.
Claim 4
Dependent Claim 158 words
A semiconductor device comprising: an insulating film, having a surface, formed on a surface of a semiconductor substrate, and having at least a hole whose diameter is smaller than 1 μm, the hole having an aspect ratio, the aspect ratio of the hole being greater than 0.7, the hole having a side wall that is substantially perpendicular to said substrate surface; and a titanium nitride film disposed thereon, extending from the surface of said semiconductor substrate, exposed by said hole, along said side wall, and having a portion on the insulating film surface, said titanium nitride film extending along said side wall having a thinnest portion, the portion of the titanium nitride film on the insulating film surface having a film thickness, the thickness of said thinnest portion of said titanium nitride film, within said hole, being more than 0.6 times as large as the film thickness of the titanium nitride film portion on said insulating film surface.
Claim 5
Dependent Claim 26 words
A semiconductor device according to claim 2, wherein the thickness of said titanium nitride film on said insulating film is between 5 nm and 700 nm.
Claim 6
Dependent Claim 31 words
A semiconductor device according to claim 2, wherein a film made of a material selected from the group consisting of aluminum and aluminum alloys is superposed on said titanium nitride film.
Claim 7
Dependent Claim 23 words
A semiconductor device according to claim 1, wherein the titanium nitride film includes chlorine in an amount of at most 2 at %.
Claim 8
Dependent Claim 30 words
A semiconductor device according to claim I, wherein the device is a memory cell including a trench-shaped capacitor, and said titanium nitride film constitutes an electrode of said trench-shaped capacitor.
Claim 9
Dependent Claim 27 words
A semiconductor device according to claim 6, wherein the titanium nitride film has an insulating material film thereon serving as a dielectric film of the trench-shaped capacitor.
Claim 10
Dependent Claim 42 words
A semiconductor device according to claim 1, wherein the surface of the semiconductor substrate exposed in the hole is a surface of an impurity-containing region provided in the substrate, the titanium nitride film being provided in direct contact with said impurity-containing region.
Claim 11
Dependent Claim 53 words
A semiconductor device according to claim 8, further comprising a conductive film made of a material selected from the group consisting of aluminum and aluminum alloys positioned on the titanium nitride film, the titanium nitride film acting as a barrier layer between the conductive film and the impurity-containing region provided in the substrate.
Claim 12
Dependent Claim 18 words
A semiconductor device according to claim 1, wherein the titanium nitride film has a principal orientation of (200).
Claim 13
Dependent Claim 29 words
A semiconductor device according to claim 10, wherein the ratio of (200) peak height to (111) peak height, for orientation of the titanium nitride film, is greater than 10.
Claim 14
Dependent Claim 21 words
A semiconductor device according to claim 1, wherein the titanium nitride film has an inner stress that is a tensile stress.

References Cited (Backward Citations)

US4743953A Cited
US4556897A Cited
US4570328A Cited
US4782380A Cited
US4784973A Cited
JPH06169969A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-01-29 1993-07-31 1994-01-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-01-29 1997-07-31 1998-01-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-01-29 2001-07-31 2002-01-30 $7700.00 Window Closed / Lapsed

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