US5074456A
Expired / Lapsed
US
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Composite electrode for plasma processes
Assignee: Lam Research Corp
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Filing: 1990-09-18
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Granted: 1991-12-24
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Expires: 2010-09-18
Abstract
Abstract An electrode assembly for a plasma reactor, such as a plasma etch or plasma-enhanced chemical vapor deposition reactor, comprises an electrode plate having a support frame attached to one surface thereof. The electrode plate is composed of a substantially pure material which is compatible with a particular reaction being performed in the reactor, while the support frame is composed of a material having desirable thermal, electrical, and structural characteristics. The support frame is bonded to the electrode plate using a bonding layer, usually a ductile metallic bonding layer, which provides effective thermal and electrical coupling while permitting a degree of thermal expansion mismatch between the support frame and the electrode plate.
Inventors
- 👤 Raymond L. Degner
- 👤 Eric H. Lenz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:32
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32431; H01J37/32532; H01J37/3255; Y; Y10; Y10S; Y10S156/00; Y10S156/914; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
125 words
An improved reactor of the type having a first electrode for supporting a substrate, an opposed electrode, and means for producing a plasma therebetween, wherein the opposed electrode has one face exposed to the first electrode and an opposite face connected to an electrical source and a thermal sink, the improvement comprising an opposed electrode including (a) an electrode plate composed of a substantially pure material and having a substantially uniform thickness and (b) a support frame composed of an electrically and thermally conductive material bonded to a back face of the plate, whereby the support frame is connected to the electrical source and thermal sink and a front face of the plate which is exposed to the first electrode is substantially free from protuberances.
Claim 2
Dependent Claim
125 words
An improved reactor of the type having a first electrode for supporting a substrate, an opposed electrode, and means for producing a plasma therebetween, wherein the opposed electrode has one face exposed to the first electrode and an opposite face connected to an electrical source and a thermal sink, the improvement comprising an opposed electrode including (a) an electrode plate composed of a substantially pure material and having a substantially uniform thickness and (b) a support frame composed of an electrically and thermally conductive material bonded to a back face of the plate, whereby the support frame is connected to the electrical source and thermal sink and a front face of the plate which is exposed to the first electrode is substantially free from protuberances.
Claim 3
Dependent Claim
42 words
An improved reactor as in claim 1, wherein the opposed electrode is mounted in an assembly having an insulating ring which is flush with the entire periphery of the exposed face, whereby the support frame is protected from exposure to the plasma.
Claim 4
Dependent Claim
14 words
An improved reactor as in claim 1, wherein the electrode plate comprises a disk.
Claim 5
Dependent Claim
30 words
An improved reactor as in claim 3, wherein the disk includes a plurality of apertures therethrough to permit the flow of a reactant gas into the space between the electrodes.
Claim 6
Dependent Claim
23 words
An improved reactor as in claim 3, wherein the support frame comprises a ring which is secured about the periphery of the disk.
Claim 7
Dependent Claim
26 words
An improved reactor as in claim 3, wherein the support frame comprises a plurality of concentric rings secured to the opposite face of the electrode disk.
Claim 8
Dependent Claim
30 words
An improved reactor as in claim 3, wherein the support frame comprises a flat plate which is secured to and covers substantially the entire opposite face of the electrode disk.
Claim 9
Dependent Claim
36 words
An improved parallel electrode reactor as in claim 5, wherein the disk as a diameter in the range from about 12 to 32 cm and a thickness in the range from about 0.1 to 2 cm.
Claim 10
Dependent Claim
35 words
An improved reactor as in claim 8, wherein the ring has an annular width in the range from about 0.5 to 5 cm and a thickness in the range from about 0.2 to 3 cm.
Claim 11
Dependent Claim
22 words
An improved reactor as in claim 1, wherein the plate is bonded to the support frame by means of a bonding layer.
Claim 12
Dependent Claim
21 words
An improved reactor as in claim 10, wherein the bonding layer is composed of a material having a low vapor pressure.
Claim 13
Dependent Claim
24 words
An improved reactor as in claim 11, wherein the bonding layer material is selected from the group consisting of indium, silver, and metal-filled epoxies.
Claim 14
Dependent Claim
18 words
An improved reactor as in claim 12, wherein the bonding layer is formed by brazing, soldering, or adhesion.
Claim 15
Dependent Claim
32 words
An improved reactor as in claim 13, wherein at least one of the plate and the support frame is metallized in the region to be bonded prior to brazing, soldering, or adhesion.
Claim 16
Dependent Claim
29 words
An improved reactor as in claim 10, wherein the bonding layer is substantially free from voids and has substantially uniform electrical and thermal conductivities through the region of bonding.
Claim 17
Dependent Claim
43 words
An improved reactor as in claim 1, wherein the electrode plate is composed of a pure material selected from the group consisting of graphite, polycrystalline silicon, quartz, glassy carbon, single crystal silicon, pyrolytic graphite, silicon carbide, alumina, zirconium, diamond-coated materials, and titanium oxides.
Claim 18
Dependent Claim
27 words
An improved reactor as in claim 1, wherein the electrically and thermally conductive material is selected from the group consisting of graphite, aluminum, copper, and stainless steel.
Claim 19
Dependent Claim
55 words
An electrode assembly comprising: an electrode composed of a substantially pure material and having a substantially uniform thickness; and a support ring bonded about the periphery of one face of the disk, leaving the other face substantially flat and free from protuberances, wherein the support ring is composed of an electrically and thermally conductive material
Claim 20
Dependent Claim
55 words
An electrode assembly comprising: an electrode composed of a substantially pure material and having a substantially uniform thickness; and a support ring bonded about the periphery of one face of the disk, leaving the other face substantially flat and free from protuberances, wherein the support ring is composed of an electrically and thermally conductive material
Claim 21
Dependent Claim
20 words
An electrode assembly as in claim 18, wherein the disk includes a plurality of apertures to permit gas flow therethrough.
Claim 22
Dependent Claim
29 words
An electrode assembly as in claim 18, further comprising at least one additional support ring mounted concentrically within the peripheral support ring or the one face of the disk.
Claim 23
Dependent Claim
25 words
An electrode assembly as in claim 18, wherein the support ring includes an interior plate which contacts substantially the entire one face of the disk.
Claim 24
Dependent Claim
34 words
An electrode assembly as in claim 18, wherein the disk has a diameter in the range from about 12 to 32 cm and a thickness in the range from about 0.1 to 2 cm.
Claim 25
Dependent Claim
35 words
An electrode assembly as in claim 18, wherein the ring has an annular width in the range from about 0.5 to 5 cm and a thickness in the range from about 0.2 to 3 cm.
Claim 26
Dependent Claim
21 words
An electrode assembly as in claim 18, wherein the disk is bonded to the ring by means of a bonding layer.
Claim 27
Dependent Claim
28 words
An electrode assembly as in claim 24, wherein the bonding layer is composed of a ductile metal or alloy or a metal-filled epoxy having a low vapor pressure.
Claim 28
Dependent Claim
25 words
An electrode assembly as in claim 25, wherein the ductile metal or alloy is selected from the group consisting of indium, silver, and metal-filled epoxies.
Claim 29
Dependent Claim
18 words
An electrode assembly as in claim 26, wherein the bonding layer is formed by brazing, soldering, or adhesion.
Claim 30
Dependent Claim
31 words
An electrode assembly as in claim 27, wherein at least one of the disk and the ring is metallized in the region to be bonded prior to brazing, soldering, or adhesion.
Claim 31
Dependent Claim
29 words
An electrode assembly as in claim 24, wherein the bonding layer is substantially free from voids and has substantially uniform electrical and thermal conductivities through the region of bonding.
Claim 32
Dependent Claim
37 words
An electrode assembly as in claim 18, wherein the material is selected from the group consisting of graphite, polycrystalline silicon, quartz, glassy carbon, single crystal silicon, pyrolytic graphite, silicon carbide, alumina, zirconium, diamond-coated materials, and titanium oxides.
Claim 33
Dependent Claim
27 words
An electrode assembly as in claim 18, wherein the electrically and thermally conductive material is selected from the group consisting of graphite, aluminum, copper, and stainless steel.
Claim 34
Dependent Claim
23 words
An electrode assembly as in claim 18, wherein the support ring is pre-stressed to impart a radially inward compression on the electrode disk.
Claim 35
Independent Claim
70 words
A method for forming an electrode assembly including a support ring and an electrode plate, said method comprising: bonding the support ring about the periphery of the electrode plate at elevated temperature, wherein the material of the electrode plate has a higher coefficient of thermal expansion than that of the electrode plate; and allowing the bonded assembly to return to room temperature, whereby the differential contraction imparts the desired stress.
Claim 36
Independent Claim
70 words
A method for forming an electrode assembly including a support ring and an electrode plate, said method comprising: bonding the support ring about the periphery of the electrode plate at elevated temperature, wherein the material of the electrode plate has a higher coefficient of thermal expansion than that of the electrode plate; and allowing the bonded assembly to return to room temperature, whereby the differential contraction imparts the desired stress.
Claim 37
Dependent Claim
23 words
A method as in claim 33, wherein the elevated temperature is chosen to be above an expected operating temperature of the electrode assembly.
Claim 38
Dependent Claim
43 words
A method as in claim 33, wherein the electrode plate is formed from a substantially pure material selected from the group consisting of graphite, polycrystalline silicon, quartz, glassy carbon, single crystal silicon, pyrolytic graphite, silicon carbide, alumina, zirconium, diamond-coated materials, and titanium oxides.
Claim 39
Dependent Claim
10 words
An electrode assembly formed by the method of claim 33.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-12-23 | 1995-06-24 | 1995-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-23 | 1999-06-24 | 1999-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-23 | 2003-06-24 | 2003-12-24 | $7700.00 | Window Closed / Lapsed |