US4330384A
Expired / Lapsed
US
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Process for plasma etching
Assignee: Hitachi Ltd
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Filing: 1979-10-29
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Granted: 1982-05-18
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Expires: 1999-10-29
Abstract
Abstract Micro-wave plasma etching is carried out with a gas containing at least SF 6 as an etching gas at a high etching rate of silicon, and a high selectivity, with an easy monitoring and a low temperature dependency.
Inventors
- 👤 Sadayuki Okudaira
- 👤 Keizo Suzuki
- 👤 Shigeru Nishimatsu
- 👤 Ichiro Kanomata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:44
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/24; H10P50/242; H10P50/267; H10P50/268
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
75 words
A process for plasma etching which comprises etching a material to be etched with a plasma in contact with said material, said plasma being formed by absorbing a micro-wave generated by a magnetron in an etching gas, said plasma being formed in a mirror magnetic field, formed by a magnetic field coil, at a position such that ions of said plasma can contact said material, wherein the etching gas contains at least SF 6 .
Claim 2
Dependent Claim
75 words
A process for plasma etching which comprises etching a material to be etched with a plasma in contact with said material, said plasma being formed by absorbing a micro-wave generated by a magnetron in an etching gas, said plasma being formed in a mirror magnetic field, formed by a magnetic field coil, at a position such that ions of said plasma can contact said material, wherein the etching gas contains at least SF 6 .
Claim 3
Dependent Claim
20 words
A process according to claim 1, wherein a pressure of the SF 6 is 2×10 -2 Pa to 10 Pa.
Claim 4
Dependent Claim
44 words
A process according to claim 1 or 2, wherein said etching gas contains, in addition to SF 6 , at least one gas selected from the group consisting of O 2 , N 2 , NH 3 , CF 4 and CH 4 .
Claim 5
Dependent Claim
30 words
A process according to claim 3, wherein the etching gas contains 3 to 20% by volume of said at least one gas on the basis of said SF 6 .
Claim 6
Dependent Claim
27 words
A process according to claim 4, wherein the material to be etched is selected from the group consisting of single crystal silicon, polycrystal silicon and amorphous silicon.
Claim 7
Dependent Claim
51 words
A process according to claim 5, wherein the material to be etched is coated with a mask of SiO 2 , Si 3 N 4 , phosphorus glass or photoresist film, whereby said plasma etches said material to be etched at a much faster rate than it etches the mask material.
Claim 8
Dependent Claim
25 words
A process according to claim 6, wherein the etching rate ratio of the material to be etched to the mask material is at least 10.
Claim 9
Dependent Claim
42 words
A process according to claim 5, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored, whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 10
Dependent Claim
28 words
A process according to claim 8, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 11
Dependent Claim
42 words
A process according to claim 4, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored, whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 12
Dependent Claim
28 words
A process according to claim 10, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 13
Dependent Claim
27 words
A process according to claim 3, wherein the material to be etched is selected from the group consisting of single crystal silicon, polycrystal silicon and amorphous silicon.
Claim 14
Dependent Claim
51 words
A process according to claim 12, wherein the material to be etched is coated with a mask of SiO 2 , Si 3 N 4 , phosphorus glass or photoresist film, whereby said plasma etches said material to be etched at a much faster rate than it etches the mask material.
Claim 15
Dependent Claim
25 words
A process according to claim 13, wherein the etching rate ratio of the material to be etched to the mask material is at least 10.
Claim 16
Dependent Claim
42 words
A process according to claim 12, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 17
Dependent Claim
28 words
A process according to claim 15, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 18
Dependent Claim
42 words
A process according to claim 3, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored, whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 19
Dependent Claim
28 words
A process according to claim 17, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 20
Dependent Claim
29 words
A process according to claim 1 or 2, wherein the material to be etched is selected from the group consisting of single crystal silicon, polycrystal silicon and amorphous silicon.
Claim 21
Dependent Claim
51 words
A process according to claim 19, wherein the material to be etched is coated with a mask of SiO 2 , Si 3 N 4 , phosphorus glass or photoresist film, whereby said plasma etches said material to be etched at a much faster rate than it etches the mask material.
Claim 22
Dependent Claim
42 words
A process according to claim 20, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored, whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 23
Dependent Claim
28 words
A process according to claim 21, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 24
Dependent Claim
25 words
A process according to claim 20, wherein the etching rate ratio of the material to be etched to the mask material is at least 10.
Claim 25
Dependent Claim
42 words
A process according to claim 19, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored, whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 26
Dependent Claim
28 words
A process according to claim 24, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 27
Dependent Claim
44 words
A process according to claim 1 or 2, wherein during the etching a bluish green light emission, emitted during the etching of said material, is monitored, whereby the end point of said etching, occurring when said bluish green light emission ceases, can be determined.
Claim 28
Dependent Claim
28 words
A process according to claim 26, wherein the emission is monitored by measuring a light emission intensity of desired wavelength within a range of 4,300 to 5,300 A.
Claim 29
Dependent Claim
79 words
A process for plasma etching which comprises etching a material to be etched with a plasma in contact with said material, said plasma being formed by absorbing a microwave generated by a magnetron in an etching gas, said plasma being formed in a mirror magnetic field, formed by a magnetic field coil and an additional magnet, at a position such that ions of said plasma can contact said material, wherein the etching gas contains at least SF 6 .
Claim 30
Dependent Claim
79 words
A process for plasma etching which comprises etching a material to be etched with a plasma in contact with said material, said plasma being formed by absorbing a microwave generated by a magnetron in an etching gas, said plasma being formed in a mirror magnetic field, formed by a magnetic field coil and an additional magnet, at a position such that ions of said plasma can contact said material, wherein the etching gas contains at least SF 6 .
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