US5804091A
Expired / Lapsed
US
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Method of preventing defects and particles produced after tungsten etch back
Assignee: Chang Liao Holdings LLC
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Filing: 1996-07-18
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Granted: 1998-09-08
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Expires: 2016-07-18
Abstract
Abstract The present invention is a method of preventing defects and particles produced after tungsten etch back. The method utilizes the Ar plasma process, baking process, and D.I. water flushing with megasonic shacking to reduce a lot of defects and particles on the surface of a wafer. Thus, the present invention can prevent defects and particles produced after tungsten etch back.
Inventors
- 👤 Yung Tsun Lo
- 👤 Guan Jiun Yi
- 👤 Chi Hen Lin
- 👤 Jyh Ming Jih
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:14
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/20; H10P70/27; H10P70/273
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
130 words
A method of preventing defects and particles produced after tungsten etch back in a wafer, the method comprising: forming a first conductive layer on a titanium nitride (TiN) layer, wherein said titanium nitride (TiN) layer is formed on the substrate of a wafer; removing said first conductive layer until said titanium nitride (TiN) layer is exposed, thereby some residues are produced on the surface of said titanium nitride (TiN) layer, wherein said residues include defects and particles; removing the residues on the surface of said titanium nitride (TiN) layer by using a plasma etch; baking the wafer; secondly removing the residues on the surface of said titanium nitride (TiN) layer again by using megasonic shaking in deionized water; and forming a second conductive layer on said titanium nitride (TiN) layer.
Claim 2
Independent Claim
130 words
A method of preventing defects and particles produced after tungsten etch back in a wafer, the method comprising: forming a first conductive layer on a titanium nitride (TiN) layer, wherein said titanium nitride (TiN) layer is formed on the substrate of a wafer; removing said first conductive layer until said titanium nitride (TiN) layer is exposed, thereby some residues are produced on the surface of said titanium nitride (TiN) layer, wherein said residues include defects and particles; removing the residues on the surface of said titanium nitride (TiN) layer by using a plasma etch; baking the wafer; secondly removing the residues on the surface of said titanium nitride (TiN) layer again by using megasonic shaking in deionized water; and forming a second conductive layer on said titanium nitride (TiN) layer.
Claim 3
Dependent Claim
22 words
The method according to claim 1, wherein forming the first conductive layer comprises depositing conductive metal using a chemical vapor deposit method.
Claim 4
Dependent Claim
15 words
The method according to claim 1, wherein said first conductive layer comprises a metal layer.
Claim 5
Dependent Claim
12 words
The method according to claim 3, wherein said metal layer comprises tungsten.
Claim 6
Dependent Claim
23 words
The method according to claim 1, wherein removing said first conductive layer comprises etching said conductive layer using a plasma etch back method.
Claim 7
Dependent Claim
23 words
The method according to claim 5, wherein said titanium nitride (TiN) layer acts as a stop point of said plasma etch back method.
Claim 8
Dependent Claim
21 words
The method according to claim 1, wherein said plasma etching process comprises using Ar ion vapor as a source of plasma.
Claim 9
Dependent Claim
27 words
The method according to claim 1, wherein the step of baking the wafer is done using a baking process with a temperature range of about 100°-200° C.
Claim 10
Dependent Claim
27 words
The method according to claim 1, wherein the step of baking the wafer is done using a baking process in a time range of about 1-20 min.
Claim 11
Dependent Claim
24 words
The method according to claim 1, wherein forming the second conductive layer comprises sputtering conductive material using sputter method of a physical vapor deposit.
Claim 12
Dependent Claim
15 words
The method according to claim 1, wherein said second conductive layer comprises a metal layer.
Claim 13
Independent Claim
115 words
A method of preventing defects and particles produced after tungsten etch back in a wafer, the method comprising the steps of: depositing, by a chemical vapor deposition process, a first metal layer comprising tungsten atop a titanium nitride (TiN) layer; etching back the tungsten until a TiN surface is exposed, a residue comprising defects and particles remaining on said exposed TiN surface; argon plasma etching the TiN surface to clean at least a portion of said residue; baking the wafer for between 1-20 minutes at a temperature between 100°-200° C.; flushing the resultant wafer with deionized water with megasonic shaking to clean the wafer surface; and sputtering a second metal layer on said TiN layer.
Claim 14
Independent Claim
115 words
A method of preventing defects and particles produced after tungsten etch back in a wafer, the method comprising the steps of: depositing, by a chemical vapor deposition process, a first metal layer comprising tungsten atop a titanium nitride (TiN) layer; etching back the tungsten until a TiN surface is exposed, a residue comprising defects and particles remaining on said exposed TiN surface; argon plasma etching the TiN surface to clean at least a portion of said residue; baking the wafer for between 1-20 minutes at a temperature between 100°-200° C.; flushing the resultant wafer with deionized water with megasonic shaking to clean the wafer surface; and sputtering a second metal layer on said TiN layer.
Claim 15
Independent Claim
123 words
A method of preventing defects and particles produced after tungsten etch back in a wafer, the method comprising the steps of: depositing, by a chemical vapor deposition process, a first metal layer comprising tungsten atop a titanium nitride (TiN) layer; etching back the tungsten until a TiN surface is exposed, a residue comprising defects and particles remaining on said exposed TiN surface; flushing the TiN surface with an argon ion vapor in a plasma process to thereby clean at least a portion of said residue; baking the wafer for between 1-20 minutes at a temperature between 100°-200° C.; flushing the resultant wafer with deionized water with megasonic shaking to clean the wafer surface; and sputtering a second metal layer on said TiN layer.
Claim 16
Independent Claim
123 words
A method of preventing defects and particles produced after tungsten etch back in a wafer, the method comprising the steps of: depositing, by a chemical vapor deposition process, a first metal layer comprising tungsten atop a titanium nitride (TiN) layer; etching back the tungsten until a TiN surface is exposed, a residue comprising defects and particles remaining on said exposed TiN surface; flushing the TiN surface with an argon ion vapor in a plasma process to thereby clean at least a portion of said residue; baking the wafer for between 1-20 minutes at a temperature between 100°-200° C.; flushing the resultant wafer with deionized water with megasonic shaking to clean the wafer surface; and sputtering a second metal layer on said TiN layer.
References Cited (Backward Citations)
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