US5401675A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of depositing conductors in high aspect ratio apertures using a collimator
Assignee: Individual
•
Filing: 1993-03-24
•
Granted: 1995-03-28
•
Expires: 2013-03-24
Abstract
Abstract A process for sputter deposition wherein high aspect ratio apertures are coated with conductive films exhibiting low bulk resistivity, low impurity concentrations, and regular morphologies. A collimator is used having an aspect ratio that approximates the aspect ratio of the apertures.
Inventors
- 👤 Pei-Ing P. Lee
- 👤 Thomas J. Licata
- 👤 Thomas L. McDevitt
- 👤 Paul C. Parries
- 👤 Scott L. Pennington
- 👤 James G. Ryan
- 👤 David C. Strippe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:24
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; C; C23; C23C; C23C14/00; C23C14/04; C23C14/042; C23C14/044; H10P; H10P14/00; H10P14/40; H10P14/42; H10P14/44; H10W20/056; H05; H05K; H05K3/00; H05K3/40; H05K3/4038; H05K3/4076
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
141 words
In a process for sputtering a barrier layer metallurgy comprising a refractory metal or refractory metal alloy from a sputter target into contact holes having side and bottom surfaces defined in an insulator arranged on a semiconductor substrate, at least some of the contact holes having an aspect ratio on the order of 2:1, the improvement comprising disposing a collimator between said sputter target and the substrate, said collimator being spaced from the substrate, said collimator having at least some openings with an aspect ratio of at least 1:1, and sputtering said refractory metal or refractory metal alloy at a pressure between approximately 0.7 mTorr and 3 mTorr, said refractory metal or refractory metal alloy being formed on said side and bottom surfaces of said contact holes and having a substantially uniform thickness at said side surfaces of said contact holes.
Claim 2
Dependent Claim
141 words
In a process for sputtering a barrier layer metallurgy comprising a refractory metal or refractory metal alloy from a sputter target into contact holes having side and bottom surfaces defined in an insulator arranged on a semiconductor substrate, at least some of the contact holes having an aspect ratio on the order of 2:1, the improvement comprising disposing a collimator between said sputter target and the substrate, said collimator being spaced from the substrate, said collimator having at least some openings with an aspect ratio of at least 1:1, and sputtering said refractory metal or refractory metal alloy at a pressure between approximately 0.7 mTorr and 3 mTorr, said refractory metal or refractory metal alloy being formed on said side and bottom surfaces of said contact holes and having a substantially uniform thickness at said side surfaces of said contact holes.
Claim 3
Dependent Claim
21 words
The process as recited in claim 1, wherein said refractory metal is sputtered at a pressure of less than 1.0 mTorr.
Claim 4
Dependent Claim
13 words
The process as recited in claim 2, wherein said refractory metal comprises titanium.
Claim 5
Dependent Claim
15 words
The process as recited in claim 2, wherein said refractory metal alloy comprises titanium nitride.
Claim 6
Dependent Claim
17 words
The process as recited in claim 4, wherein said deposition is carried out in an N2 ambient.
Claim 7
Dependent Claim
125 words
In a sputtering process for depositing a refractory metal or refractory metal alloy layer from a sputter target onto a substrate having at least some depressions therein with aspect ratios on the order of 2:1, each of said depressions having bottom and side surfaces, the improvement comprising disposing a collimator between the sputter target and the substrate, said collimator being spaced from the substrate, and sputtering said refractory metal or refractory metal alloy layer at a pressure between approximately 0.7 mTorr and 3 mTorr and at a substrate temperature of approximately 150° C., said refractory metal or refractory metal alloy layer being formed on said side and bottom surfaces of said depressions and having a substantially uniform thickness at said side surfaces of said depressions.
Claim 8
Dependent Claim
125 words
In a sputtering process for depositing a refractory metal or refractory metal alloy layer from a sputter target onto a substrate having at least some depressions therein with aspect ratios on the order of 2:1, each of said depressions having bottom and side surfaces, the improvement comprising disposing a collimator between the sputter target and the substrate, said collimator being spaced from the substrate, and sputtering said refractory metal or refractory metal alloy layer at a pressure between approximately 0.7 mTorr and 3 mTorr and at a substrate temperature of approximately 150° C., said refractory metal or refractory metal alloy layer being formed on said side and bottom surfaces of said depressions and having a substantially uniform thickness at said side surfaces of said depressions.
Claim 9
Dependent Claim
159 words
A process for forming a Ti/TiN barrier layer within a 2:1 aspect ratio aperture formed within a passivation layer arranged on a substrate, comprising the steps of: sputtering a layer of titanium onto the substrate through a collimator having 1:1 aspect ratio openings therein, said collimator being spaced from the substrate, said layer of titanium being sputtered at a pressure between 0.7 mTorr and 3 mTorr; sputtering a layer of titanium nitride onto said layer of titanium through said collimator, said second sputtering step being carried out in a working gas consisting essentially of N2 and a pressure between 0.7 mTorr and 3 mTorr, said layers of titanium and titanium nitfide being formed on said sides and bottom of said aperture, and having a substantially uniform thickness on said sides of said aperture; and annealing said layers of titanium and titanium nitride in an N 2 ambient to convert titanium on said sides of said aperture to titanium nitride.
Claim 10
Dependent Claim
159 words
A process for forming a Ti/TiN barrier layer within a 2:1 aspect ratio aperture formed within a passivation layer arranged on a substrate, comprising the steps of: sputtering a layer of titanium onto the substrate through a collimator having 1:1 aspect ratio openings therein, said collimator being spaced from the substrate, said layer of titanium being sputtered at a pressure between 0.7 mTorr and 3 mTorr; sputtering a layer of titanium nitride onto said layer of titanium through said collimator, said second sputtering step being carried out in a working gas consisting essentially of N2 and a pressure between 0.7 mTorr and 3 mTorr, said layers of titanium and titanium nitfide being formed on said sides and bottom of said aperture, and having a substantially uniform thickness on said sides of said aperture; and annealing said layers of titanium and titanium nitride in an N 2 ambient to convert titanium on said sides of said aperture to titanium nitride.
Claim 11
Dependent Claim
17 words
The process as recited in claim 7, wherein said pressure is not greater than approximately 1 mTorr.
Claim 12
Dependent Claim
132 words
A process for sputtering a layer of titanium nitride onto a substrate having at least one depression having side and bottom surfaces, said at least one depression having an aspect ratio on the order of 2:1, comprising the steps of forming said at least one depression on said substrate, and sputtering said layer of titanium nitfide onto the substrate through a collimator spaced from the substrate, said sputtering step being carded out at a pressure between approximately 0.7 mTorr and 3 mTorr, and in a working gas consisting essentially of N2, said layer of titanium nitride being deposited on said side and bottom surfaces of said at least one depression, said layer of titanium nitride being deposited at a substantially uniform thickness on said side surfaces of said at least one depression.
Claim 13
Dependent Claim
132 words
A process for sputtering a layer of titanium nitride onto a substrate having at least one depression having side and bottom surfaces, said at least one depression having an aspect ratio on the order of 2:1, comprising the steps of forming said at least one depression on said substrate, and sputtering said layer of titanium nitfide onto the substrate through a collimator spaced from the substrate, said sputtering step being carded out at a pressure between approximately 0.7 mTorr and 3 mTorr, and in a working gas consisting essentially of N2, said layer of titanium nitride being deposited on said side and bottom surfaces of said at least one depression, said layer of titanium nitride being deposited at a substantially uniform thickness on said side surfaces of said at least one depression.
Claim 14
Dependent Claim
17 words
The process as recited in claim 9, wherein said pressure is not greater than approximately 1 mTorr.
Claim 15
Dependent Claim
20 words
The process as recited in claim 10, wherein said substrate is heated to approximately 1500° C. during said sputtering step.
Claim 16
Dependent Claim
22 words
The process as recited in claim 6, wherein said sputtering process is carried out at a pressure of less than 1.0 mTorr.
References Cited (Backward Citations)
US4116791A
Cited
US4226082A
Cited
EP0044372A2
Cited
US4724060A
Cited
US4725566A
Cited
JPS6217173A
Cited
JPS62199033A
Cited
US4849079A
Cited
US4756810A
Cited
US4783248A
Cited
JPS63310965A
Cited
US4824544A
Cited
US4962414A
Cited
US4897709A
Cited
US4822753A
Cited
US5112693A
Cited
US4920073A
Cited
US4994162A
Cited
US5026470A
Cited
US5008217A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-03-27 | 1998-09-26 | 1999-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-03-27 | 2002-09-26 | 2003-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-03-27 | 2006-09-26 | 2007-03-28 | $7700.00 | Window Closed / Lapsed |