US4444617A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reactive ion etching of molybdenum silicide and N+ polysilicon
Assignee: Newport Fab LLC
•
Filing: 1983-01-06
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Granted: 1984-04-24
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Expires: 2003-01-06
Abstract
Abstract An anisotropic etching processing for fabricating a solid state device which consists of the steps of providing a layer of silicon on the substrate and depositing a layer of molysilicide on the silicon layer. The molysilicide layer is then masked to define a pattern thereon. The unmasked portions of the molysilicide layer is then etched using a plasma etch gas mixture consisting essentially of CF4, C2F6, O2 in the approximate ratio 50:5:2 in percent by volume. Etching through polysilicon is performed anisotropically using a plasma etch gas mixture consisting essentially of CCl2F2 and C2F6 in approximately the ratio 10:1 in percent by volume.
Inventors
- 👤 Eugene C. Whitcomb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:14
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
93 words
An anisotropic etching processing for fabricating a solid state device on a substrate comprising the steps of: providing a layer of silicon on said substrate; depositing a layer of molysilicide on said silicon layer; masking portions of said molysilicide layer to define a pattern thereon; and etching through the unmasked portions of said molysilicide layer using a plasma etch gas mixture consisting essentially of a mixture of CF 4 , C 2 F 6 , O 2 in percent by volume in the range: ______________________________________
CF.sub.4
76-94%
C.sub.2 F.sub.6
4-16%
O.sub.2
2-8%
______________________________________
Claim 2
Dependent Claim
93 words
An anisotropic etching processing for fabricating a solid state device on a substrate comprising the steps of: providing a layer of silicon on said substrate; depositing a layer of molysilicide on said silicon layer; masking portions of said molysilicide layer to define a pattern thereon; and etching through the unmasked portions of said molysilicide layer using a plasma etch gas mixture consisting essentially of a mixture of CF 4 , C 2 F 6 , O 2 in percent by volume in the range: ______________________________________
CF.sub.4
76-94%
C.sub.2 F.sub.6
4-16%
O.sub.2
2-8%
______________________________________
Claim 3
Dependent Claim
16 words
A process as defined in claim 1 wherein said layer of silicon consists of N+ polysilicon.
Claim 4
Dependent Claim
15 words
The process as defined in claim 1, wherein said layer of silicon consists of monosilicon.
Claim 5
Dependent Claim
30 words
The process as defined in claim 1, wherein said masking step comprises depositing a layer of photoresist over said molysilicide layer and etching said photoresist layer to form a pattern.
Claim 6
Dependent Claim
22 words
A method as defined in claim 4 further comprising the step of subsequently stripping the remaining portions of said layer of photoresist.
Claim 7
Dependent Claim
32 words
A method as defined in claim 1, wherein said mixture of CF 4 , C 2 F 6 , and O 2 in percent by volume is approximately in the ratio 50:5:2.
Claim 8
Dependent Claim
40 words
A gas for use in reactive ion etching of molysilicide consisting essentially of: CF 4 , C 2 F 6 , and O 2 in percent by volume in the range: ______________________________________
CF.sub.4
76-94%
C.sub.2 F.sub.6
4-16%
O.sub.2
2-8%
______________________________________
Claim 9
Dependent Claim
40 words
A gas for use in reactive ion etching of molysilicide consisting essentially of: CF 4 , C 2 F 6 , and O 2 in percent by volume in the range: ______________________________________
CF.sub.4
76-94%
C.sub.2 F.sub.6
4-16%
O.sub.2
2-8%
______________________________________
Claim 10
Dependent Claim
27 words
A gas as defined in claim 1, consisting essentially of the composition, in percent by volume, of approximately: ______________________________________
CF.sub.4
89%
C.sub.2 F.sub.6
7%
O.sub.2
4%
______________________________________
Claim 11
Dependent Claim
117 words
An anisotropic etching processing for fabricating a solid state device on a substrate comprising the steps of: providing a layer of silicon on said substrate; depositing a layer of polysilicon on said silicon layer; depositing a layer of molysilicide on said polysilicon layer; masking portions of said molysilicide layer to define a pattern thereon; etching through the unmasked portions of said molysilicide layer using a first plasma etch gas mixture consisting essentially of CF 4 , C 2 F 6 , and O 2 in percent by volume in the range: ______________________________________
CF.sub.4 76-94%
C.sub.2 F.sub.6
4-16%
O.sub.2 2-8%; and
______________________________________ etching through the unmasked portions of said polysilicon layer using a second plasma etch gas mixture.
Claim 12
Dependent Claim
117 words
An anisotropic etching processing for fabricating a solid state device on a substrate comprising the steps of: providing a layer of silicon on said substrate; depositing a layer of polysilicon on said silicon layer; depositing a layer of molysilicide on said polysilicon layer; masking portions of said molysilicide layer to define a pattern thereon; etching through the unmasked portions of said molysilicide layer using a first plasma etch gas mixture consisting essentially of CF 4 , C 2 F 6 , and O 2 in percent by volume in the range: ______________________________________
CF.sub.4 76-94%
C.sub.2 F.sub.6
4-16%
O.sub.2 2-8%; and
______________________________________ etching through the unmasked portions of said polysilicon layer using a second plasma etch gas mixture.
Claim 13
Dependent Claim
82 words
An anisotropic etching processing for fabricating a solid state device on a substrate comprising the steps of: providing a layer of silicon on said substrate; depositing a layer of N+ polysilicon on said silicon layer; masking portions of said polysilicon layer to define a pattern thereon; etching through the unmasked portions of said polysilicon layer using a plasma etch gas mixture consisting essentially of CCl 2 F 2 , and C 2 F 6 in the ratio 10:1 in percent by volume.
Claim 14
Dependent Claim
82 words
An anisotropic etching processing for fabricating a solid state device on a substrate comprising the steps of: providing a layer of silicon on said substrate; depositing a layer of N+ polysilicon on said silicon layer; masking portions of said polysilicon layer to define a pattern thereon; etching through the unmasked portions of said polysilicon layer using a plasma etch gas mixture consisting essentially of CCl 2 F 2 , and C 2 F 6 in the ratio 10:1 in percent by volume.
Claim 15
Dependent Claim
15 words
The process as defined in claim 10, wherein said layer of silicon consists of monosilicon.
Claim 16
Dependent Claim
30 words
The process as defined in claim 10, wherein said masking step comprises depositing a layer of photoresist over said polysilicon layer and etching said photoresist layer to form a pattern.
Claim 17
Dependent Claim
22 words
A method as defined in claim 12, further comprising the step of subsequently stripping the remaining portions of said layer of photoresist.
Claim 18
Dependent Claim
32 words
A gas for use in reactive ion etching of polysilicon consisting of substantially of: CCl 2 F 2 , and C 2 F 6 in the ratio 10:1 in percent by volume.
Claim 19
Dependent Claim
32 words
A gas for use in reactive ion etching of polysilicon consisting of substantially of: CCl 2 F 2 , and C 2 F 6 in the ratio 10:1 in percent by volume.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-04-24 | 1987-10-24 | 1988-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-24 | 1991-10-24 | 1992-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-24 | 1995-10-24 | 1996-04-24 | $7700.00 | Window Closed / Lapsed |