Titanium nitride film in contact hole with large aspect ratio

• US 4,897,709 A
• Filed: 05/26/1988
• Issued: 01/30/1990
• Est. Priority Date: 04/15/1988
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yokoyama, Natsuki, Hinode, Kenji, Homma, Yoshio, Mukai, Kiichiro
• Primary Examiner(s): Mintel, William
• Application Number:
  US07/199,269
• Time in Patent Office: 614 Days
• Field of Search: 357/68, 357/54, 357/54 N, 357/71, 357/55, 357/55 R, 357/55 C, 357/23.6, 437/197, 437/203, 437/190, 437/243
• US Class Current: 257/301
• CPC Class Codes: H01L 21/76841 Barrier, adhesion or liner layers
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76877 Filling of holes, grooves or trenches, e.g. vias, with conductive material
• CPC Class Codes: H01L 23/53223 Additional layers associated with aluminium layers, e.g. adhesion, barrier, cladding layers
• 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: H10B 12/31 having a storage electrode stacked over the transistor

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.

Claims

1. 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.

5. A semiconductor device according to claim 1, wherein the titanium nitride film includes chlorine in an amount of at most 2 at %.

8. 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.

9. 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.

10. A semiconductor device according to claim 1, wherein the titanium nitride film has a principal orientation of (200).

11. 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.

12. A semiconductor device according to claim 1, wherein the titanium nitride film has an inner stress that is a tensile stress.

2. 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 μ

m, 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.

3. 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.

4. 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.

6. 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.

7. 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.