US5730834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorine residue removal after tungsten etchback
Assignee: Adeia Semiconductor Technologies LLC
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Filing: 1996-03-29
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Granted: 1998-03-24
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Expires: 2016-03-29
Abstract
Abstract Forming tungsten plugs allows for a conformal step coverage into contacts in semiconductor wafer processing. By rinsing the wafers after the tungsten etchback but before the wafers have a chance to enter an oxygen-containing environment, the amount of fluorine-containing residue removed from the wafer can be increased. In this way, the connection between the tungsten plugs and a metallization layer can be improved.
Inventors
- 👤 Calvin Gabriel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:47
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/20; H10P70/27; H10P70/273; Y; Y10; Y10S; Y10S438/00; Y10S438/907; Y10S438/908
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
63 words
A method of processing a wafer, the wafer including a tungsten deposition layer comprising: etching back the tungsten deposition layer on the wafer in an enclosed processing equipment, the etching step producing fluorine-containing residue on the tungsten as a by-product; and rinsing the wafer in bath in the enclosed processing equipment before exposing the wafer to the atmosphere outside of the processing equipment.
Claim 2
Independent Claim
63 words
A method of processing a wafer, the wafer including a tungsten deposition layer comprising: etching back the tungsten deposition layer on the wafer in an enclosed processing equipment, the etching step producing fluorine-containing residue on the tungsten as a by-product; and rinsing the wafer in bath in the enclosed processing equipment before exposing the wafer to the atmosphere outside of the processing equipment.
Claim 3
Dependent Claim
15 words
The method of claim 1, wherein the rinsing step comprises rinsing the wafer in water.
Claim 4
Dependent Claim
15 words
The method of claim 1, wherein the rinsing step is done in an oxygen-free environment.
Claim 5
Dependent Claim
18 words
The method of claim 1, wherein the etching and rinsing steps are done in a multiple chamber etcher.
Claim 6
Dependent Claim
19 words
The method of claim 4, wherein the rinsing step is done in a separate chamber from the etching step.
Claim 7
Dependent Claim
15 words
The method of claim 1, wherein the etching step is done with a fluorine-containing gas.
Claim 8
Dependent Claim
19 words
The method of claim 6, wherein the rinsing step includes rinsing the wafer with water heated above room temperature.
Claim 9
Dependent Claim
13 words
The method of claim 6, wherein the etching step in an oxygen-free environment.
Claim 10
Dependent Claim
27 words
The method of claim 1, wherein the wafer contains a layer including titanium nitride and the rinsing step comprises rinsing a titanium fluoride product from the wafer.
Claim 11
Dependent Claim
20 words
The method of claim 1, wherein the etching step comprises etching the tungsten deposition layer back to form tungsten plugs.
Claim 12
Dependent Claim
17 words
The method of claim 1, wherein the rising step comprises supplying nitrogen to maintain an oxygen-free environment.
Claim 13
Dependent Claim
16 words
The method of claim 1, further comprising a metallization layer deposition step after the rinse step.
Claim 14
Independent Claim
61 words
A method of processing a wafer, the wafer including a tungsten deposition layer comprising: etching the tungsten deposition layer on the wafer to form tungsten plugs, the etching step producing a fluorine-containing residue on the tungsten plugs as a by-product; and rinsing the wafer in an oxygen-free environment to remove some of the fluorine before exposing the wafer to the atmosphere.
Claim 15
Independent Claim
61 words
A method of processing a wafer, the wafer including a tungsten deposition layer comprising: etching the tungsten deposition layer on the wafer to form tungsten plugs, the etching step producing a fluorine-containing residue on the tungsten plugs as a by-product; and rinsing the wafer in an oxygen-free environment to remove some of the fluorine before exposing the wafer to the atmosphere.
Claim 16
Dependent Claim
15 words
The method of claim 1, wherein the rinsing step comprises rinsing the wafer in water.
Claim 17
Dependent Claim
18 words
The method of claim 1, wherein the etching and rinsing steps are done in a multiple chamber etcher.
Claim 18
Dependent Claim
15 words
The method of claim 1, wherein the etching step is done with a fluorine-containing gas.
Claim 19
Dependent Claim
27 words
The method of claim 1, wherein the wafer contains a layer including titanium nitride and the rinsing step comprises rinsing a titanium fluoride product from the wafer.
Claim 20
Dependent Claim
16 words
The method of claim 1, further comprising a metallization layer deposition step after the rinse step.
Claim 21
Dependent Claim
17 words
The method of claim 1, wherein the rinsing step comprises rinsing in a liquid including ammonium fluoride.
Claim 22
Independent Claim
54 words
A method of processing a wafer, the wafer including a tungsten deposition layer comprising: etching tungsten on the wafer to form tungsten plugs, the etching step producing a fluorine-containing residue on the tungsten plugs as a by-product; and washing the wafer with a liquid including ammonium fluoride to remove some of the fluorine-containing residue.
Claim 23
Independent Claim
54 words
A method of processing a wafer, the wafer including a tungsten deposition layer comprising: etching tungsten on the wafer to form tungsten plugs, the etching step producing a fluorine-containing residue on the tungsten plugs as a by-product; and washing the wafer with a liquid including ammonium fluoride to remove some of the fluorine-containing residue.
References Cited (Backward Citations)
US5200017A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-03-23 | 2001-09-22 | 2002-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-03-23 | 2005-09-22 | 2006-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-03-23 | 2009-09-22 | 2010-03-24 | $7700.00 | Window Closed / Lapsed |