US6565729B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for electrochemically depositing metal on a semiconductor workpiece
Assignee: Applied Materials Inc
•
Filing: 2000-12-07
•
Granted: 2003-05-20
•
Expires: 2020-12-07
Abstract
Abstract A process for metallization of a workpiece, such as a semiconductor workpiece. In an embodiment, an alkaline electrolytic copper bath is used to electroplate copper onto a seed layer, electroplate copper directly onto a barrier layer material, or enhance an ultra-thin copper seed layer which has been deposited on the barrier layer using a deposition process such as PVD. The resulting copper layer provides an excellent conformal copper coating that fills trenches, vias, and other microstructures in the workpiece. When used for seed layer enhancement, the resulting copper seed layer provide an excellent conformal copper coating that allows the microstructures to be filled with a copper layer having good uniformity using electrochemical deposition techniques. Further, copper layers that are electroplated in the disclosed manner exhibit low sheet resistance and are readily annealed at low temperatures.
Inventors
- 👤 LinLin Chen
- 👤 Gregory J. Wilson
- 👤 Paul R. McHugh
- 👤 Robert A. Weaver
- 👤 Thomas L. Ritzdorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:25
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/041; C; C25; C25D; C25D17/00; C25D17/10; C25D3/00; C25D3/02; C25D3/38; C25D5/00; C25D5/08; C25D5/10; C25D5/48; C25D5/50; C25D5/67; C25D7/00; C25D7/12; C25D7/123; H10P; H10P14/00; H10P14/40; H10P14/46; H10P14/47; H10W20/033; H10W20/042; H10W20/043; H10W20/056; C25D17/02; C25D17/12; H10W20/0425; Y; Y10; Y10S; Y10S204/00; Y10S204/07; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493
Claims Analysis
Total Claims: 65
Claim 1
Independent Claim
170 words
A process for applying a metallization interconnect structure, comprising: (a) providing a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying barrier layer, and the ultra-thin metal seed layer being a non-continuous layer having voids; (b) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer within a principal fluid chamber of a reactor to provide an enhanced seed layer using a second deposition process, that is different from the first deposition process, comprising supplying electroplating power to a plurality of concentric anodes disposed at different positions within the principal fluid flow chamber relative to the workpiece; and (c) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 2
Dependent Claim
170 words
A process for applying a metallization interconnect structure, comprising: (a) providing a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying barrier layer, and the ultra-thin metal seed layer being a non-continuous layer having voids; (b) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer within a principal fluid chamber of a reactor to provide an enhanced seed layer using a second deposition process, that is different from the first deposition process, comprising supplying electroplating power to a plurality of concentric anodes disposed at different positions within the principal fluid flow chamber relative to the workpiece; and (c) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein the additional metal is copper.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein the first electrochemical deposition step occurs in an alkaline bath.
Claim 5
Dependent Claim
21 words
The process of claim 3 wherein the alkaline bath comprises metal ions and an agent effective in complexing the metal ions.
Claim 6
Dependent Claim
20 words
The process of claim 1 wherein the ultra-thin metal seed layer that is repaired is formed by physical vapor deposition.
Claim 7
Dependent Claim
25 words
The process of claim 1 wherein the ultra-thin metal seed layer that is repaired has a thickness of less than or equal to 500 Angstroms.
Claim 8
Dependent Claim
21 words
The process of claim 6 wherein the ultra-thin metal layer that is repaired has a thickness of 100 to 250 Angstroms.
Claim 9
Dependent Claim
22 words
The process of claim 1 wherein the complexing agent comprises one or more complexing agents selected from EDTA, ED, and polycarboxylic acid.
Claim 10
Dependent Claim
28 words
The process of claim 8 wherein the complexing agent comprises EDTA and the EDTA in the bath has a concentration within the range of 0.03 to 1.0 M.
Claim 11
Dependent Claim
30 words
The process of claim 8 wherein the complexing agent comprises ED and wherein the ED in the electrolytic bath has a concentration within the range of 0.03 to 1.0 M.
Claim 12
Dependent Claim
30 words
The process of claim 9 wherein the complexing agent comprises citric acid and the citric acid in the bath has a concentration within the range of 0.03 to 1.0 M.
Claim 13
Dependent Claim
41 words
The process of claim 1 wherein the step of subjecting the workpiece to a further electrochemical deposition process occurs in an acidic electrolytic solution to complete deposition of the metal to a thickness needed for the formation of the interconnect structure.
Claim 14
Dependent Claim
36 words
The process of claim 12 , further comprising subjecting the workpiece to a rinsing process after electrochemical deposition in the alkaline bath and prior to the further electrochemical metal deposition process in an acidic electrolytic solution.
Claim 15
Dependent Claim
50 words
The process of claim 1 , wherein the enhanced seed layer has a thickness at all points on sidewalls of substantially all recessed features distributed within the workpiece that is equal to or greater than 10% of the enhanced seed layer thickness over the exteriorly disposed surface of the workpiece.
Claim 16
Dependent Claim
32 words
The process of claim 1 , wherein one or more of the plurality of concentric anodes used to repair the ultra-thin metal seed layer is disposed in close proximity to the workpiece.
Claim 17
Dependent Claim
52 words
The process of claim 15 , wherein the plurality of concentric anodes used for the repair of the ultra-thin metal seed layer are arranged at varying distances may be from the workpiece from an innermost one of the plurality of concentric anodes to an outermost one of the plurality of concentric anodes.
Claim 18
Dependent Claim
50 words
The process of claim 15 , wherein the plurality of concentric anodes used for the repair of the ultra-thin metal seed layer are arranged at increasing distances from the workpiece from an innermost one of the plurality of concentric anodes to an outermost one of the plurality of concentric anodes.
Claim 19
Dependent Claim
28 words
The process of claim 1 , wherein one or more of the plurality of concentric anodes used to repair the ultra-thin metal seed layer is a virtual anode.
Claim 20
Dependent Claim
60 words
The process of claim 18 , wherein the virtual anode used in the repair of the ultra-thin metal seed layer comprises an anode chamber housing having a processing fluid inlet and a processing fluid outlet, the processing fluid outlet being disposed in close proximity to the workpiece, and at least one conductive anode element disposed in the anode chamber housing.
Claim 21
Dependent Claim
20 words
The process of claim 19 , wherein the at least one conductive anode element is formed from an inert material.
Claim 22
Dependent Claim
49 words
The process of claim 1 , wherein the principal fluid chamber in which the repair of the ultra-thin metal seed layer is carried out is defined in an upper portion thereof by an angled wall, the angled wall supporting one or more of the plurality of the concentric anodes.
Claim 23
Dependent Claim
61 words
The process of claim 1 , wherein the repair of the ultra-thin metal seed layer is carried out in a principal fluid flow chamber that comprises an inlet disposed at a lower portion thereof and that is configured to provide a venturi effect that facilitates recirculation of a chemical processing fluid in a lower portion of the principal fluid flow chamber.
Claim 24
Dependent Claim
51 words
The process of claim 1 , wherein during the repair of the ultra-thin metal seed layer, at least two of the plurality of anodes are independently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two of the plurality of anodes.
Claim 25
Dependent Claim
68 words
The process of claim 23 , wherein the controlling of the supply of power for at least one of the independently controlled anodes is based on one or more user input parameters and a plurality of predetermined sensitivity values associated with the workpiece, the predetermined sensitivity values corresponding to process perturbations resulting from perturbations of an electrical power supply parameter for the at least one independently controlled electrode.
Claim 26
Dependent Claim
14 words
The process of claim 24 , wherein the electrical power parameter is electrical current.
Claim 27
Dependent Claim
22 words
The process of claim 24 , wherein the sensitivity values are logically arranged within a controller as one or more Jacobian matrices.
Claim 28
Dependent Claim
30 words
The process of claim 24 , wherein the at least one user input parameter comprises a thickness of the additional metal to be deposited on the ultra-thin metal seed layer.
Claim 29
Dependent Claim
200 words
A process for applying a metallization interconnect structure, comprising: (a) providing a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids; (b) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer within a principal fluid chamber of a reactor to provide an enhanced seed layer using a second deposition process, that is different from the first deposition process, comprising supplying electroplating power to a plurality of electrodes within the principal fluid flow chamber, wherein at least two of the plurality of electrodes are interdependently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two electrodes during repair of the ultra-thin metal seed layer; and (c) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 30
Dependent Claim
200 words
A process for applying a metallization interconnect structure, comprising: (a) providing a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids; (b) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer within a principal fluid chamber of a reactor to provide an enhanced seed layer using a second deposition process, that is different from the first deposition process, comprising supplying electroplating power to a plurality of electrodes within the principal fluid flow chamber, wherein at least two of the plurality of electrodes are interdependently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two electrodes during repair of the ultra-thin metal seed layer; and (c) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 31
Dependent Claim
11 words
The process of claim 28 wherein the additional metal is copper.
Claim 32
Dependent Claim
23 words
The process of claim 28 wherein the ultra-thin seed layer is formed on a barrier layer deposited on a surface of the workpiece.
Claim 33
Dependent Claim
15 words
The process of claim 28 wherein the electrochemical deposition step occurs in an alkaline bath.
Claim 34
Dependent Claim
25 words
The process of claim 28 wherein the ultra-thin metal seed layer that is repaired has a thickness of less than or equal to 500 Angstroms.
Claim 35
Dependent Claim
68 words
The process of claim 28 , wherein the controlling of the supply of power for at least one of the independently controlled electrodes is based on one or more user input parameters and a plurality of predetermined sensitivity values associated with the workpiece, the predetermined sensitivity values corresponding to process perturbations resulting from perturbations of an electrical power supply parameter for the at least one independently controlled electrode.
Claim 36
Dependent Claim
17 words
At The process of claim 33 , wherein the electrical power parameter is electrical current or potential.
Claim 37
Dependent Claim
22 words
The process of claim 33 , wherein the sensitivity values are logically arranged within a controller as one or more Jacobian matrices.
Claim 38
Dependent Claim
30 words
The process of claim 33 , wherein the at least one user input parameter comprises a thickness of the additional metal to be deposited on the ultra-thin metal seed layer.
Claim 39
Dependent Claim
187 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids, comprising (a) subjecting the workpiece to an electrochemical deposition process that is different from the first deposition process in an alkaline electroplating bath comprising metal ions complexed with a complexing agent such that additional metal is deposited on the ultra-thin copper seed layer to thereby repair the seed layer resulting in an enhanced seed layer, the second deposition process being carried out by supplying electroplating power to a plurality of concentric anodes disposed at different positions relative to the workpiece within a principal fluid flow chamber of a reactor; and (b) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 40
Dependent Claim
187 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids, comprising (a) subjecting the workpiece to an electrochemical deposition process that is different from the first deposition process in an alkaline electroplating bath comprising metal ions complexed with a complexing agent such that additional metal is deposited on the ultra-thin copper seed layer to thereby repair the seed layer resulting in an enhanced seed layer, the second deposition process being carried out by supplying electroplating power to a plurality of concentric anodes disposed at different positions relative to the workpiece within a principal fluid flow chamber of a reactor; and (b) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 41
Dependent Claim
11 words
The process of claim 37 wherein the additional metal is copper.
Claim 42
Dependent Claim
24 words
The process of claim 37 wherein the ultra-thin seed layer is formed on a barrier layer deposited on a sur ace of the workpiece.
Claim 43
Dependent Claim
22 words
The process of claim 37 wherein the complexing agent comprises one or more complexing agents selected from EDTA, ED, and polycarboxylic acid.
Claim 44
Dependent Claim
25 words
The process of claim 37 wherein the ultra-thin metal seed layer that is repaired has a thickness of less than or equal to 500 Angstroms.
Claim 45
Dependent Claim
51 words
The process of claim 37 , wherein during the repair of the ultra-thin metal seed layer, at least two of the plurality of anodes are independently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two of the plurality of anodes.
Claim 46
Dependent Claim
68 words
The process of claim 42 , wherein the controlling of the supply of power for a given one of the independently controlled electrodes is based on one or more user input parameters and the plurality of predetermined sensitivity values associated with the workpiece, the predetermined sensitivity values corresponding to process perturbations resulting from perturbations of an electrical power supply parameter for the at least one independently controlled electrode.
Claim 47
Dependent Claim
22 words
The process of claim 43 , wherein the sensitivity values are logically arranged within a controller as one or more Jacobian matrices.
Claim 48
Dependent Claim
30 words
The process of claim 43 , wherein the at least one user input parameter comprises a thickness of the additional metal to be deposited on the ultra-thin metal seed layer.
Claim 49
Dependent Claim
208 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin copper seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin copper seed layer to an underlying layer, and the ultra-thin copper seed layer being a non-continuous layer having voids, comprising: (a) subjecting the workpiece to an electrochemical deposition process that is different from the first deposition process in an alkaline electroplating bath comprising metal ions complexed with a complexing agent such that additional metal is deposited on the ultra-thin copper seed layer to thereby repair the seed layer resulting in an enhanced seed layer, comprising supplying electroplating power to a plurality of electrodes within the principal fluid flow chamber, wherein at least two of the plurality of electrodes are independently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two electrodes during repair of the ultra-thin copper seed layer; and (b) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 50
Dependent Claim
208 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin copper seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin copper seed layer to an underlying layer, and the ultra-thin copper seed layer being a non-continuous layer having voids, comprising: (a) subjecting the workpiece to an electrochemical deposition process that is different from the first deposition process in an alkaline electroplating bath comprising metal ions complexed with a complexing agent such that additional metal is deposited on the ultra-thin copper seed layer to thereby repair the seed layer resulting in an enhanced seed layer, comprising supplying electroplating power to a plurality of electrodes within the principal fluid flow chamber, wherein at least two of the plurality of electrodes are independently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two electrodes during repair of the ultra-thin copper seed layer; and (b) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer.
Claim 51
Dependent Claim
11 words
The process of claim 46 wherein the additional metal is copper.
Claim 52
Dependent Claim
23 words
The process of claim 46 wherein the ultra-thin seed layer is formed on a barrier layer deposited on a surface of the workpiece.
Claim 53
Dependent Claim
22 words
The process of claim 46 wherein the complexing agent comprises one or more complexing agents selected from EDTA, ED, and polycarboxylic acid.
Claim 54
Dependent Claim
25 words
The process of claim 46 wherein the ultra-thin metal seed layer that is repaired has a thickness of less than or equal to 500 Angstroms.
Claim 55
Dependent Claim
69 words
An The process of claim 46 , wherein the controlling of the supply of power for at least one of the independently controlled electrodes is based on one or more user input parameters and a plurality of predetermined sensitivity values associated with the workpiece, the predetermined sensitivity values corresponding to process perturbations resulting from perturbations of an electrical power supply parameter for the at least one independently controlled electrode.
Claim 56
Dependent Claim
14 words
The process of claim 51 , wherein the electrical power parameter is electrical current.
Claim 57
Dependent Claim
22 words
The process of claim 51 , wherein the sensitivity values are logically arranged within a controller as one or more Jacobian matrices.
Claim 58
Dependent Claim
30 words
The process of claim 51 , wherein the at least one user input parameter comprises a thickness of the additional metal to be deposited on the ultra-thin metal seed layer.
Claim 59
Dependent Claim
169 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids, comprising: (a) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer within a principal fluid flow chamber of a reactor to provide an enhanced seed layer using a second deposition process that is different from the first deposition process; and (b) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer, comprising supplying electroplating power to a plurality of concentric anodes disposed at different positions within the principal fluid flow chamber relative to the workpiece.
Claim 60
Dependent Claim
169 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids, comprising: (a) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer within a principal fluid flow chamber of a reactor to provide an enhanced seed layer using a second deposition process that is different from the first deposition process; and (b) electrolytically depositing a metal on the enhanced seed layer under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer, comprising supplying electroplating power to a plurality of concentric anodes disposed at different positions within the principal fluid flow chamber relative to the workpiece.
Claim 61
Dependent Claim
21 words
The process of claim 55 , wherein the second deposition process that repairs the seed layer is an electroless plating process.
Claim 62
Dependent Claim
41 words
The process of claim 55 , wherein the second deposition process that repairs the said layer also comprises supplying electroplating power to a plurality of concentric anodes disposed at different positions within the principal fluid flow chamber relative to the workpiece.
Claim 63
Dependent Claim
193 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids, comprising: (a) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer to provide an enhanced seed layer using a second deposition process that is different from the first deposition process; and (b) electrolytically depositing a metal on the enhanced seed layer within a principal fluid chamber of a reactor under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer, comprising supplying electroplating power to a plurality of electrodes within the principal fluid flow chamber wherein at least two of the plurality of electrodes are independently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two electrodes during deposition.
Claim 64
Dependent Claim
193 words
A process for applying a metallization interconnect structure to a workpiece on which an ultra-thin metal seed layer has been formed using a first deposition process, the first deposition process being a vapor-phase deposition process that anchors the ultra-thin metal seed layer to an underlying layer, and the ultra-thin metal seed layer being a non-continuous layer having voids, comprising: (a) repairing the ultra-thin metal seed layer by electrochemically depositing additional metal on the ultra-thin metal seed layer to provide an enhanced seed layer using a second deposition process that is different from the first deposition process; and (b) electrolytically depositing a metal on the enhanced seed layer within a principal fluid chamber of a reactor under conditions in which the deposition rate of the electrolytic deposition process is substantially greater than the deposition rate of the process used to repair the metal seed layer, comprising supplying electroplating power to a plurality of electrodes within the principal fluid flow chamber wherein at least two of the plurality of electrodes are independently connected to an electrical power supply, further comprising independently controlling the supply of electrical power to the at least two electrodes during deposition.
Claim 65
Dependent Claim
21 words
The process of claim 58 , wherein the second deposition process that repairs the seed layer is an electroless plating process.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-05-19 | 2006-11-18 | 2007-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-05-19 | 2010-11-18 | 2011-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-05-19 | 2014-11-18 | 2015-05-20 | $7700.00 | Window Closed / Lapsed |