EP0163446A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus for and method of controlling magnetron sputter device having separate confining magnetic fields to separate targets subject to separate discharges
Assignee: Varian Semiconductor Equipment Associates Inc
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Filing: 1985-05-10
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Granted: —
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Expires: 2005-05-10
Abstract
Abstract A cathode sputter magnetron device is controlled so that there is a uniformity of material supplied to workpieces over the lives of plural geometrically spaced targets from which material is sputtered. Each target is subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field. The relative powers of the separate plasma discharges are controlled so that the relative powers change as a function of target erosion condition. The impedances of the separate discharges are controlled by varying each separate magnetic field in response to variable currents applied to electromagnets.
Inventors
- 👤 Donald M. Mintz
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 13:17
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/34; H; H01; H01J; H01J37/00; H01J37/32; H01J37/34; H01J37/3411; H01J37/345; H01J37/3458; C23C14/54; H01J37/3402; H01J37/3405; H01J37/3408
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
101 words
Apparatus for controlling a cathode sputter magnetron device so that there is a uniformity of material supplied to a work piece over the lives of plural geometrically spaced targets from which material is sputtered, each target being subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field, the control apparatus comprising means for deriving a first signal indicative of the target erosion condition, and means responsive to the first signal for controlling the relative powers of the separate plasma discharges so that the relative powers change as a function of the erosion condition.
Claim 2
Dependent Claim
101 words
Apparatus for controlling a cathode sputter magnetron device so that there is a uniformity of material supplied to a work piece over the lives of plural geometrically spaced targets from which material is sputtered, each target being subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field, the control apparatus comprising means for deriving a first signal indicative of the target erosion condition, and means responsive to the first signal for controlling the relative powers of the separate plasma discharges so that the relative powers change as a function of the erosion condition.
Claim 3
Dependent Claim
16 words
The apparatus of claim 1 further including means for controlling the impedances of the separate discharges.
Claim 4
Dependent Claim
18 words
The apparatus of claim 2 wherein the impedance control means includes means for varying each separate magnetic field.
Claim 5
Dependent Claim
76 words
The apparatus of claim 3 wherein each magnetic field is derived by an electromagnet, the impedance control means including means for comparing the impedance of a first of the discharges with a set value therefor to derive an error signal, means responsive to the error signal for controlling the current applied to the electromagnet for the first discharge to the set value therefor and for controlling the current applied to the electromagnet for a- second discharge.
Claim 6
Dependent Claim
41 words
The apparatus of claim 4 wherein the current control means includes means for controlling the current applied to the electromagnet for the second discharge so it is a constant factor of the current applied to the electromagnet for the first discharge.
Claim 7
Dependent Claim
105 words
The apparatus of claim 1 wherein a first of the targets is initially closer to the center of the workpiece than a second of the targets and the distance of the second target to the center of the target relative to the distance of the first target to the center of the target increases as the targets erode during use, said means for controlling including means for adjusting-the powers of the discharges for the first and second targets so that as target erosion occurs the amount of power supplied to the second target relative to the amount of power supplied to the first target increases.
Claim 8
Dependent Claim
93 words
A cathode sputter device for uniformly sup - plying material to a work piece over the lives of plural geometrically spaced targets from which material is sputtered, comprising means for subjecting each target to a separate plasma discharge, said subjecting means including a separate magnetic field source for each plasma discharge, means for deriving a first signal indicative of the target erosion condition, and means responsive to the first signal for controlling the relative powers of the separate plasma discharges so that the relative powers change as a function of the erosion condition.
Claim 9
Dependent Claim
93 words
A cathode sputter device for uniformly sup - plying material to a work piece over the lives of plural geometrically spaced targets from which material is sputtered, comprising means for subjecting each target to a separate plasma discharge, said subjecting means including a separate magnetic field source for each plasma discharge, means for deriving a first signal indicative of the target erosion condition, and means responsive to the first signal for controlling the relative powers of the separate plasma discharges so that the relative powers change as a function of the erosion condition.
Claim 10
Dependent Claim
16 words
The device of claim 7 further including means for controlling the impedances of the separate discharges.
Claim 11
Dependent Claim
18 words
The device of claim 8 wherein the impedance control means includes means for varying each separate magnetic field.
Claim 12
Dependent Claim
76 words
The device of claim 9 wherein each magnetic field is derived by an electromagnet, the impedance control means including means for comparing the impedance of a first of the discharges with a set value therefor to derive an error signal, means responsive to the error signal for controlling the current applied to the electromagnet for the first discharge to the set value therefor and for controlling the current applied to the electromagnet for a second discharge.
Claim 13
Dependent Claim
41 words
The device of claim 10 wherein the current control means includes means for controlling the current applied to the electromagnet for the second discharge so it is a constant factor of the current applied to the electromagnet for the first discharge.
Claim 14
Dependent Claim
105 words
The device of claim 7 wherein a first of the targets is initially closer to the center of the workpiece than a second of the targets and the distance of the second target to the center of the target relative to the distance of the first target to the center of the target increases as the targets erode during use, said means for controlling including means for adjusting the powers of the discharges for the first and second targets'so that as target erosion occurs the amount of power supplied to the second target relative to the amount of power supplied to the first target increases.
Claim 15
Dependent Claim
37 words
The device of claim 12 further including means for mounting the targets so they are concentric with an axis that extends through the center of the workpiece, with the second target being outside of the first target.
Claim 16
Dependent Claim
79 words
The device of claim 13 wherein the workpiece has a planar surface at right angles to the axis, the planar workpiece surface being responsive to material sputtered from the targets, the first target having a planar particle emitting surface and the second target having a concave emitting surface, said mounting means including means for mounting the lowest portion of the concave emitting surface in a plane that is closer to the workpiece planar surface than the planar emitting surface.
Claim 17
Independent Claim
79 words
A method of controlling a cathode sputter magnetron device so that there is a uniformity of material supplied to workpieces over the lives of plural geometrically spaced targets from which material is sputtered, each target being subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field, the method comprising controlling the relative powers of the separate plasma discharges so that the relative powers change as a function of target erosion condition.
Claim 18
Independent Claim
79 words
A method of controlling a cathode sputter magnetron device so that there is a uniformity of material supplied to workpieces over the lives of plural geometrically spaced targets from which material is sputtered, each target being subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field, the method comprising controlling the relative powers of the separate plasma discharges so that the relative powers change as a function of target erosion condition.
Claim 19
Dependent Claim
14 words
The method of claim 15 further including controlling the impedances of the separate discharges.
Claim 20
Dependent Claim
16 words
The method of claim 16 wherein the impedances are controlled by varying each separate magnetic field.
Claim 21
Dependent Claim
71 words
The method of claim 17 wherein each magnetic field is derived by an electromagnet, the impedance being controlled by comparing the impedance of a first of the discharges with a set value therefor, controlling the current applied to the electromagnet for the first discharge in response to the comparison of the first discharge impedance with the set value therefor, and controlling the current applied to the electromagnet for a second discharge.
Claim 22
Dependent Claim
34 words
The method of claim 18 wherein the current for the electromagnet for the second discharge is controlled so it is a constant factor of the current applied to the electromagnet for the first discharge.
Claim 23
Dependent Claim
103 words
The method of claim 15 wherein a first of the targets is initially closer to the center of the workpiece than a second of the targets and the distance of the second target to the center of the target relative to the distance of the first target to the center of the target increases as the targets erode during use, said control step including adjusting the powers of the discharges for the first and second targets so that as target erosion occurs the amount of power supplied to the second target relative to the amount of power supplied to the first target increases.
Claim 24
Dependent Claim
118 words
Apparatus for controlling a cathode sputter magnetron device so that there is a uniformity of material supplied to workpieces over the lives of plural geometrically spaced targets from which material is sputtered, each target being subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field, the control apparatus including means for deriving a first.signal indicative of the impedance of a first of the discharges, and means responsive to the first signal for controlling the impedance of the first discharge to a set value therefor and for controlling the impedance of a second discharge in response to an indication of the deviation of the first signal from a set value therefor.
Claim 25
Dependent Claim
118 words
Apparatus for controlling a cathode sputter magnetron device so that there is a uniformity of material supplied to workpieces over the lives of plural geometrically spaced targets from which material is sputtered, each target being subjected to a separate plasma discharge that is confined to the associated target by a separate magnetic field, the control apparatus including means for deriving a first.signal indicative of the impedance of a first of the discharges, and means responsive to the first signal for controlling the impedance of the first discharge to a set value therefor and for controlling the impedance of a second discharge in response to an indication of the deviation of the first signal from a set value therefor.
Claim 26
Dependent Claim
18 words
The apparatus of claim 21 wherein the impedance control means includes means for varying each separate magnetic field.
Claim 27
Dependent Claim
55 words
The apparatus of claim 22 wherein each magnetic field is derived by an electromagnet, the impedance control means including means responsive to the deviation indication for controlling (a) the current applied to the electromagnet for the first discharge to a set value therefor and (b) the current applied to the electromagnet for a second discharge.
Claim 28
Dependent Claim
41 words
The apparatus of claim 23 wherein the current control means includes means for controlling the current applied to the electromagnet for the second discharge so it is a constant factor of the current applied to the electromagnet for the first discharge.
References Cited (Backward Citations)
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