US4948458A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for producing magnetically-coupled planar plasma
Assignee: Lam Research Corp
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Filing: 1989-08-14
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Granted: 1990-08-14
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Expires: 2009-08-14
Abstract
Abstract An apparatus for producing a planar plasma in a low pressure process gas includes a chamber and an external planar coil. Radiofrequency resonant current is induced in the planar coil which in turn produces a planar magnetic field within the exclosure. The magnetic field causes circulating flux of electrons which in turn produces a planar region of ionic and radical species. The system may be used for plasma treatment of a variety of planar articles, typically semiconductor wafers which are oriented parallel to the plasma within the enclosure.
Inventors
- 👤 John S. Ogle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:11
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32009; H01J37/32082; H01J37/321; H10; H10P; H10P50/00; H05; H05H; H05H1/00; H05H1/24; H05H1/46
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
88 words
An apparatus for producing a planar plasma, said apparatus comprising: an enclosure having an interior bounded at least in part by a dielectric shield; means for introducing a process gas to the interior of the enclosure; an electrically-conductive substantially planar coil disposed outside the enclosure proximate the dielectric shield; and means for coupling a radiofrequency source to the coil, said coupling means including (1) means for matching the impedance of the radiofrequency source to the coil and (2) means for tuning the resulting circuit to provide for resonance.
Claim 2
Independent Claim
88 words
An apparatus for producing a planar plasma, said apparatus comprising: an enclosure having an interior bounded at least in part by a dielectric shield; means for introducing a process gas to the interior of the enclosure; an electrically-conductive substantially planar coil disposed outside the enclosure proximate the dielectric shield; and means for coupling a radiofrequency source to the coil, said coupling means including (1) means for matching the impedance of the radiofrequency source to the coil and (2) means for tuning the resulting circuit to provide for resonance.
Claim 3
Dependent Claim
15 words
An apparatus as in claim 1, wherein the planar coil is arranged as a spiral.
Claim 4
Dependent Claim
18 words
An apparatus as in claim 1, wherein the planar coil is arranged as a series of concentric loops.
Claim 5
Dependent Claim
14 words
An apparatus as in claim 1, wherein the dielectric shield is composed of quartz.
Claim 6
Dependent Claim
24 words
An apparatus as in claim 1, wherein the means for introducing a process gas includes a plurality of ports which circumscribe the dielectric shield.
Claim 7
Dependent Claim
18 words
An apparatus as in claim 1, wherein the impedance matching means includes a pair of mutually rotatable coils.
Claim 8
Dependent Claim
14 words
An apparatus as in claim 1, wherein the tuning means includes a variable capacitor.
Claim 9
Independent Claim
85 words
An apparatus for treating articles with a plasma, said apparatus comprising: an enclosure having an interior bounded at least in part by a dielectric shield; means within the enclosure for supporting the article to be treated in a preselected plane; an electrically conductive planar coil disposed outside the enclosure proximate the dielectric shield, said coil being oriented parallel to the preselected plane; means for coupling a radiofrequency source to the planar coil; and means for introducing a process gas into the enclosure under controlled pressure.
Claim 10
Independent Claim
85 words
An apparatus for treating articles with a plasma, said apparatus comprising: an enclosure having an interior bounded at least in part by a dielectric shield; means within the enclosure for supporting the article to be treated in a preselected plane; an electrically conductive planar coil disposed outside the enclosure proximate the dielectric shield, said coil being oriented parallel to the preselected plane; means for coupling a radiofrequency source to the planar coil; and means for introducing a process gas into the enclosure under controlled pressure.
Claim 11
Dependent Claim
14 words
An apparatus as in claim 8, wherein the coil is arranged as a spiral.
Claim 12
Dependent Claim
14 words
An apparatus as in claim 8, wherein the coil is arranged as concentric loops.
Claim 13
Dependent Claim
40 words
An apparatus as in claim 8, wherein the means for coupling the radiofrequency generator includes (1) means for matching the impedance of the radiofrequency source to the planar coil and (2) means for tuning the circuit to provide for resonance.
Claim 14
Dependent Claim
18 words
An apparatus as in claim 11, wherein the impedance matching means includes a pair of mutually rotatable coils.
Claim 15
Dependent Claim
14 words
An apparatus as in claim 11, wherein the tuning means includes a variable capacitor.
Claim 16
Dependent Claim
14 words
An apparatus as in claim 8, wherein the dielectric shield is composed of quartz.
Claim 17
Dependent Claim
24 words
An apparatus as in claim 8, wherein the means for introducing the process gas includes a plurality of ports which circumscribe the dielectric shield.
Claim 18
Dependent Claim
25 words
An apparatus as in claim 8, further comprising means for applying a radiofrequency potential across the planar coil and the supporting means within the enclosure.
Claim 19
Independent Claim
64 words
A method for treating article with a plasma, said method comprising: placing the article within an enclosure; introducing a process gas to the enclosure at a controlled pressure; and resonating a radiofrequency current in a substantially planar coil located outside the enclosure proximate a dielectric shield formed in the enclosure, whereby a planar plasma substantially parallel to the coil is formed inside the enclosure.
Claim 20
Independent Claim
64 words
A method for treating article with a plasma, said method comprising: placing the article within an enclosure; introducing a process gas to the enclosure at a controlled pressure; and resonating a radiofrequency current in a substantially planar coil located outside the enclosure proximate a dielectric shield formed in the enclosure, whereby a planar plasma substantially parallel to the coil is formed inside the enclosure.
Claim 21
Dependent Claim
24 words
A method as in claim 17, wherein the article is a planar article which is oriented in a plane parallel to the planar coil.
Claim 22
Dependent Claim
14 words
A method as in claim 18, wherein the planar article is a semiconductor wafer.
Claim 23
Dependent Claim
13 words
A method as in claim 17, wherein the process gas is an etchant.
Claim 24
Dependent Claim
12 words
A method as in claim 20, wherein the etchant is a halocarbon.
Claim 25
Dependent Claim
21 words
A method as in claim 17, wherein the planar coil is tuned to resonate at a frequency of about 13.56 MHz.
Claim 26
Dependent Claim
43 words
A method as in claim 17, further comprising applying a radiofrequency potential across the planar coil and a surface within the enclosure on which the article is supported, whereby plasma ions and radicals are accelerated in a direction normal to the planar article.
Claim 27
Dependent Claim
18 words
A method as in claim 23, wherein the radiofrequency potential is at a frequency of about 13.56 MHz.
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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) | 1993-08-13 | 1994-02-12 | 1994-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-13 | 1998-02-12 | 1998-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-13 | 2002-02-12 | 2002-08-14 | $7700.00 | Window Closed / Lapsed |