US5545591A
Expired / Lapsed
US
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Method for forming an aluminum film used as an interconnect in a semiconductor device
Assignee: NEC Corp
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Filing: 1995-11-06
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Granted: 1996-08-13
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Expires: 2015-11-06
Abstract
Abstract A method for forming an interconnect comprises the steps of first covering an overall surface including a surface of a contact hole or a via-hole with a film of one of refractory metal and refractory metal compound and then depositing on the covered surface an aluminum film grown by a chemical vapor deposition (CVD) process using organic aluminum or trialkylamine-alane as a source material under a substrate temperature between 100° C. and 180° C. The organic aluminum is one of dimethylaluminum hydride, tri-isobutyl aluminum, trimethylamine-alane, and diethylaluminum hydride. The trialkylamine-alane is one of trimethylamine-alane and triethylamine-alane. Such aluminum film has good step-coverage so that, even when the diameter is small and the aspect ratio is high, the film can be deposited without an void being formed in the deposited film in the contact hole or the via-hole.
Inventors
- 👤 Kazumi Sugai
- 👤 Hidekazu Okabayashi
- 👤 Shunji Kishida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:58
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10P; H10P14/00; H10P14/40; H10P14/42; H10P14/43
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
126 words
A method for forming an interconnect which includes an interconnect hole having a depth/diameter aspect ratio α larger than 1, said method comprising the steps of: providing said interconnect hole on a surface of a semiconductor substrate; covering a surface including a surface of said interconnect hole with a film of one of refractory metal and refractory metal compound; and depositing on the covered surface an aluminum film grown by a chemical vapor deposition process using dimethylaluminum hydride as a source material at a substrate temperature selected such that a ratio between a rate of deposition and a maximum deposition rate becomes 1/(1+4α), said maximum deposition rate being a maximum rate of deposition obtained when all film formation conditions other than said substrate temperature are unchanged.
Claim 2
Independent Claim
126 words
A method for forming an interconnect which includes an interconnect hole having a depth/diameter aspect ratio α larger than 1, said method comprising the steps of: providing said interconnect hole on a surface of a semiconductor substrate; covering a surface including a surface of said interconnect hole with a film of one of refractory metal and refractory metal compound; and depositing on the covered surface an aluminum film grown by a chemical vapor deposition process using dimethylaluminum hydride as a source material at a substrate temperature selected such that a ratio between a rate of deposition and a maximum deposition rate becomes 1/(1+4α), said maximum deposition rate being a maximum rate of deposition obtained when all film formation conditions other than said substrate temperature are unchanged.
Claim 3
Dependent Claim
19 words
A method for forming an interconnect according to claim 1, in which said interconnect hole is a contact hole.
Claim 4
Dependent Claim
18 words
A method for forming an interconnect according to claim 1, in which said interconnect hole is a via-hole.
Claim 5
Dependent Claim
21 words
A method for forming an interconnect according to claim 1, in which said film of refractory metal is a titanium film.
Claim 6
Dependent Claim
24 words
A method for forming an interconnect according to claim 1, in which said film of refractory metal compound is a film of titanium nitride.
Claim 7
Dependent Claim
24 words
A method for forming an interconnect according to claim 1, in which said film of refractory metal compound is a film of titanium tungsten.
Claim 8
Dependent Claim
69 words
A method for forming an interconnect according to claim 1, wherein a lower limit of said substrate temperature is 100° C. and an optimum substrate temperature is about 130° C., said optimum temperature being a temperature at which said interconnect hole is covered by TiN, has an aspect ratio α of about 3, and is filled with uniform step coverage utilizing a chemical vapor deposition process using dimethylaluminum hydride.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-08-13 | 2000-02-12 | 2000-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-08-13 | 2004-02-12 | 2004-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-08-13 | 2008-02-12 | 2008-08-13 | $7700.00 | Window Closed / Lapsed |