US5789321A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming a barrier metal layer made of titanium nitride on a silicon substrate
Assignee: NEC Corp
•
Filing: 1997-06-19
•
Granted: 1998-08-04
•
Expires: 2017-06-19
Abstract
Abstract A low pressure chloride chemical vapor deposition method for depositing a titanium nitride film within a contact hole formed in an insulation film overlying a silicon substrate is carried out by reacting a nitrogen source gas in plasma state, which contains gas molecules decomposed or excited, with a titanium source gas in non-plasma state, which contains titanium chloride undecomposed so that the titanium nitride film has a good step coverage and a low concentration of residual chlorine.
Inventors
- 👤 Yoshio Ohshita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:18
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/40; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
180 words
A method of depositing a titanium nitride film on exposed silicon in a semiconductor device comprising the steps of: heating the exposed silicon on which the titanium nitride film is to be deposited; and reacting on the heated silicon (A) a nitrogen source gas which is the primary source of reactant nitrogen for the titanium nitride film, the nitrogen source gas being in a plasma state, and (B) a titanium source gas which is the primary source of the reactant titanium for the titanium nitride film, the titanium source gas being in a non-plasma state, reacting said source gas (A) and said source gas (B) on the heated silicon in the presence of (C) a nitrogen gas in a non-plasma state which is not a source of reactant nitrogen for the titanium nitride film at a pressure of 30 Pa, and a flow rate of said gas (C) is three times a flow rate of said source gas (B), whereby the nitrogen source gas and the titanium source gas react to form the titanium nitride film on the heated silicon.
Claim 2
Independent Claim
180 words
A method of depositing a titanium nitride film on exposed silicon in a semiconductor device comprising the steps of: heating the exposed silicon on which the titanium nitride film is to be deposited; and reacting on the heated silicon (A) a nitrogen source gas which is the primary source of reactant nitrogen for the titanium nitride film, the nitrogen source gas being in a plasma state, and (B) a titanium source gas which is the primary source of the reactant titanium for the titanium nitride film, the titanium source gas being in a non-plasma state, reacting said source gas (A) and said source gas (B) on the heated silicon in the presence of (C) a nitrogen gas in a non-plasma state which is not a source of reactant nitrogen for the titanium nitride film at a pressure of 30 Pa, and a flow rate of said gas (C) is three times a flow rate of said source gas (B), whereby the nitrogen source gas and the titanium source gas react to form the titanium nitride film on the heated silicon.
Claim 3
Dependent Claim
31 words
The method of claim 1, wherein said source gas (A) comprises a gas selected from the group consisting of NH 3 , N 2 , and N 2 H 4 .
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein said source gas (B) is TiCl 4 .
Claim 5
Dependent Claim
30 words
The method of claim 1, wherein said gas (C) comprises a gas selected from the group consisting of NH 3 , N 2 , and N 2 H 4 .
Claim 6
Dependent Claim
17 words
the method of claim 4, wherein said gas (C) is the same as said source gas (A).
Claim 7
Independent Claim
244 words
A method of depositing a thin titanium nitride film with a low concentration of residual chlorine on exposed silicon substrate at a bottom of a contact hole in a semiconductor device comprising the steps of: heating the exposed silicon substrate on which the titanium nitride film is to be deposited; and introducing into a chamber containing the heated silicon substrate (A) a high reactivity, decomposed, nitrogen source gas selected from the group consisting of NH 3 , N 2 , and N 2 H 4 which is the primary source of reactant nitrogen for the titanium nitride film, the nitrogen source gas being in a plasma state, and (B) a low reactivity, undecomposed, TiCl 4 source gas which is the primary source of the reactant titanium for the titanium nitride film, the TiCl 4 source gas being in a non-plasma state, reacting said source gas (A) and said source gas (B) on the heated silicon in the presence of (C) a nitrogen gas in a non-plasma state which is not a source of reactant nitrogen for the titanium nitride film at a pressure of 30 Pa, and a flow rate of said gas (C) is three times a flow rate of said source gas (B), whereby said source gas (A) and said source gas (B) react to form a monatomic titanium nitride film on the exposed silicon at the bottom of the contact hole with a low concentration of residual chlorine in the film.
Claim 8
Independent Claim
244 words
A method of depositing a thin titanium nitride film with a low concentration of residual chlorine on exposed silicon substrate at a bottom of a contact hole in a semiconductor device comprising the steps of: heating the exposed silicon substrate on which the titanium nitride film is to be deposited; and introducing into a chamber containing the heated silicon substrate (A) a high reactivity, decomposed, nitrogen source gas selected from the group consisting of NH 3 , N 2 , and N 2 H 4 which is the primary source of reactant nitrogen for the titanium nitride film, the nitrogen source gas being in a plasma state, and (B) a low reactivity, undecomposed, TiCl 4 source gas which is the primary source of the reactant titanium for the titanium nitride film, the TiCl 4 source gas being in a non-plasma state, reacting said source gas (A) and said source gas (B) on the heated silicon in the presence of (C) a nitrogen gas in a non-plasma state which is not a source of reactant nitrogen for the titanium nitride film at a pressure of 30 Pa, and a flow rate of said gas (C) is three times a flow rate of said source gas (B), whereby said source gas (A) and said source gas (B) react to form a monatomic titanium nitride film on the exposed silicon at the bottom of the contact hole with a low concentration of residual chlorine in the film.
Claim 9
Independent Claim
15 words
The method of claims, wherein the contact hole has a diameter of about 0.5 micrometers.
Claim 10
Dependent Claim
30 words
The method of claim 6, wherein said gas (C) comprises a gas selected from the group consisting of NH 3 , N 2 , and N 2 H 4 .
Claim 11
Dependent Claim
17 words
The method of claim 8, wherein said gas (C) is the same as said source gas (A).
References Cited (Backward Citations)
US4022872A
Cited
US5002646A
Cited
US4987102A
Cited
US5616518A
Cited
US5525543A
Cited
US5271963A
Cited
US5348587A
Cited
US5508881A
Cited
US5567243A
Cited
US5593511A
Cited
US5665640A
Cited
US5591483A
Cited
US5567483A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-08-03 | 2002-02-02 | 2002-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-08-03 | 2006-02-02 | 2006-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-08-03 | 2010-02-02 | 2010-08-04 | $7700.00 | Window Closed / Lapsed |