Patent US5879989A successfully refreshed from Google Patents.
US5879989A
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Method for fabricating nonvolatile memory device using disposable layer
Assignee: SK Hynix Inc
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Filing: 1997-01-03
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Granted: 1999-03-09
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Expires: 2017-01-03
Abstract
Abstract A nonvolatile memory device includes: a substrate having field and active regions; a field insulating layer formed on the field region; a first gate insulating layer formed on the active region; a floating gate formed on the first gate insulating layer and on a portion of the field insulating layer, the portion extending from the first gate insulating layer, the floating gate being separated from the field insulating layer; a second gate insulating layer formed on the surface of the floating gate; a control gate formed on the second gate insulating layer; and an impurity region formed in a portion of the substrate, the portion being placed on both sides of the control gate.
Inventors
- 👤 Min-Gyu Lim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:13
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0411; H10D30/60; H10D30/68; H10D30/681; H10D30/684; H10D30/685
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
113 words
A method for fabricating a nonvolatile memory device, comprising the steps of: forming a field insulating layer on a field region of a substrate; forming a disposable layer on said field insulating layer; forming a first gate insulating layer on said active region; forming a floating gate on said first gate insulating layer and on portions of said disposable layer; removing said disposable layer; forming a second gate insulating layer on the surface of said floating gate; forming a control gate on said second gate insulating layer; and forming an impurity region in a portion of said substrate, said portion of said substrate being on at least one side of said control gate.
Claim 2
Independent Claim
113 words
A method for fabricating a nonvolatile memory device, comprising the steps of: forming a field insulating layer on a field region of a substrate; forming a disposable layer on said field insulating layer; forming a first gate insulating layer on said active region; forming a floating gate on said first gate insulating layer and on portions of said disposable layer; removing said disposable layer; forming a second gate insulating layer on the surface of said floating gate; forming a control gate on said second gate insulating layer; and forming an impurity region in a portion of said substrate, said portion of said substrate being on at least one side of said control gate.
Claim 3
Dependent Claim
33 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said method further comprises: forming a sidewall against a side of said field insulating layer and said disposable layer.
Claim 4
Dependent Claim
44 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said field insulating layer, and said first and second gate insulating layers are formed of a silicon oxide layer, and said disposable layer is formed of a silicon nitride layer.
Claim 5
Dependent Claim
25 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said floating gate and said control gate are formed of polysilicon.
Claim 6
Dependent Claim
24 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said step of removing said disposable layer includes isotropic etching.
Claim 7
Dependent Claim
20 words
The method for fabricating a nonvolatile memory device as claimed in claim 5, wherein said isotropic etching is wet etching.
Claim 8
Dependent Claim
27 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said step of forming said impurity region includes ion-implanting impurities into said substrate.
Claim 9
Dependent Claim
24 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said floating gate is separated from said field insulating layer.
Claim 10
Dependent Claim
26 words
The method for fabricating a nonvolatile memory device as claimed in claim 1, wherein said impurity region is formed on both sides of said control gate.
Claim 11
Independent Claim
126 words
A method for fabricating a nonvolatile memory device, comprising the steps of: forming a field insulating layer on a field region of a substrate; forming a first gate insulating layer on an active region of said substrate; forming a disposable layer on said field insulating layer; forming a floating gate on said first gate insulating layer and on portions of said disposable layer; removing said disposable layer such that said floating gate extends beyond said active region and partially over said field regions; forming a second gate insulating layer on said floating gate; and forming a control gate on said second gate insulating layer and said field insulating layer such that portions of said control gate are between said floating gate and said field insulating layer.
Claim 12
Independent Claim
126 words
A method for fabricating a nonvolatile memory device, comprising the steps of: forming a field insulating layer on a field region of a substrate; forming a first gate insulating layer on an active region of said substrate; forming a disposable layer on said field insulating layer; forming a floating gate on said first gate insulating layer and on portions of said disposable layer; removing said disposable layer such that said floating gate extends beyond said active region and partially over said field regions; forming a second gate insulating layer on said floating gate; and forming a control gate on said second gate insulating layer and said field insulating layer such that portions of said control gate are between said floating gate and said field insulating layer.
Claim 13
Independent Claim
98 words
A method for fabricating a nonvolatile memory device, comprising the steps of; forming a field insulating layer on a field region of a substrate; forming a first gate insulating layer on an active region of said substrate; forming a floating gate on said first gate insulating layer said over portions of said field insulating layer; forming a second gate insulating layer on said floating gate; and forming a control gate on said second gate insulating layer and said field insulating layer such that portions of said control gate are between said floating gate and said field insulating layer.
Claim 14
Independent Claim
98 words
A method for fabricating a nonvolatile memory device, comprising the steps of; forming a field insulating layer on a field region of a substrate; forming a first gate insulating layer on an active region of said substrate; forming a floating gate on said first gate insulating layer said over portions of said field insulating layer; forming a second gate insulating layer on said floating gate; and forming a control gate on said second gate insulating layer and said field insulating layer such that portions of said control gate are between said floating gate and said field insulating layer.
Claim 15
Dependent Claim
24 words
The method for fabricating a nonvolatile memory device as claimed in claim 10, wherein said step of removing said disposable layer includes isotropic etching.
Claim 16
Dependent Claim
20 words
The method for fabricating a nonvolatile memory device as claimed in claim 12, wherein said isotropic etching is wet etching.
Claim 17
Dependent Claim
36 words
The method for fabricating a nonvolatile memory device as claimed in claim 10, wherein said method further comprises the step of forming a sidewall against a side of said field insulating layer and said disposable layer.
Claim 18
Dependent Claim
44 words
The method for fabricating a nonvolatile memory device as claimed in claim 10, wherein said field insulating layer, and said first and second gate insulating layers are formed of a silicon oxide layer, and said disposable layer is formed of a silicon nitride layer.
Claim 19
Dependent Claim
25 words
The method for fabricating a nonvolatile memory device as claimed in claim 10, wherein said floating gate and said control gate are formed of polysilicon.
Claim 20
Dependent Claim
33 words
The method for fabricating a nonvolatile memory device as claimed in claim 10, further comprising: forming an impurity region in a substrate being located on at least one side of said control gate.
Claim 21
Dependent Claim
27 words
The method for fabricating a nonvolatile memory device as claimed in claim 17, wherein said step of forming said impurity region includes ion-implanting impurities into said substrate.
Claim 22
Dependent Claim
26 words
The method for fabricating a nonvolatile memory device as claimed in claim 17, wherein said impurity region is formed on both sides of said control gate.
Claim 23
Dependent Claim
40 words
The method as in claim 11, further comprising: forming sidewalls against exposed sides of said field insulating layer and said disposable layer; wherein, after said disposable layer is removed, said sidewalls extend above a height of said field insulating layer.
References Cited (Backward Citations)
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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) | 2002-03-08 | 2002-09-07 | 2003-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-08 | 2006-09-07 | 2007-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-08 | 2010-09-07 | 2011-03-09 | $7700.00 | Window Closed / Lapsed |