Patent US5879955A successfully refreshed from Google Patents.
US5879955A
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Method for fabricating an array of ultra-small pores for chalcogenide memory cells
Assignee: Round Rock Research LLC
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Filing: 1995-06-07
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Granted: 1999-03-09
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Expires: 2015-06-07
Abstract
Abstract A method for fabricating an array of ultra-small pores for use in chalcogenide memory cells. A layer of a first material is applied onto a substrate. A portion of the layer of the first material is then removed to define an upper surface with vertical surfaces extending therefrom to a lower surface in the first layer of the first material. A fixed layer of a second material is then applied onto the vertical surfaces of the first layer of the first material. The fixed layer of the second material has a first thickness. A second layer of the first material is then applied onto the fixed layer of the second material. The fixed layer of the second material is then removed to define an array of pores in the first material layers. The pores thus defined have minimum lateral dimensions ranging from approximately 50 to 500 Angstroms and cross sectional areas greater than or equal to the first thickness of the second layer squared. The pores thus defined are further equally spaced from adjacent pores by a spacing ranging from approximately 0.25 to 0.5 microns. The pores thus defined may then be used to fabricate an array of chalcogenide memory cells.
Inventors
- 👤 Fernando Gonzalez
- 👤 Raymond A. Turi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:39
CPC Classifications
H; H10; H10N; H10N70/00; H10N70/011; H10N70/061; H10N70/068; H10B; H10B63/00; H10B63/80; H10N70/20; H10N70/231; H10N70/801; H10N70/821; H10N70/826; H10N70/881; H10N70/882; H10N70/8828; Y; Y10; Y10S; Y10S257/00; Y10S257/90
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
141 words
A method of fabricating an array of pores, comprising the steps of: applying a first layer of a first material onto a substrate; removing a portion of said first layer of said first material to define an upper surface with generally vertical surfaces extending therefrom to a lower surface in said first layer of said first material, said upper surface being generally horizontal and including a horizontal surface that is generally cross shaped; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said first material, said fixed layer of said second material having a first thickness; applying a second layer of said first material onto said fixed layer of said second material; and removing said fixed layer of said second material to define said array of pores in said first material layers.
Claim 2
Independent Claim
141 words
A method of fabricating an array of pores, comprising the steps of: applying a first layer of a first material onto a substrate; removing a portion of said first layer of said first material to define an upper surface with generally vertical surfaces extending therefrom to a lower surface in said first layer of said first material, said upper surface being generally horizontal and including a horizontal surface that is generally cross shaped; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said first material, said fixed layer of said second material having a first thickness; applying a second layer of said first material onto said fixed layer of said second material; and removing said fixed layer of said second material to define said array of pores in said first material layers.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms.
Claim 4
Dependent Claim
29 words
The method of claim 1, wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared.
Claim 5
Dependent Claim
45 words
The method of claim 1, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms; and wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared.
Claim 6
Dependent Claim
23 words
The method of claim 1, wherein said cross shaped horizontal upper surface includes a pair of arms extending relative to a central point.
Claim 7
Dependent Claim
24 words
The method of claim 5, wherein said arms of said cross shaped horizontal upper surface range in length from about 0.5 to 1.0 microns.
Claim 8
Dependent Claim
21 words
The method of claim 1, wherein said upper surface is surrounded by a recess defined in part by said lower surface.
Claim 9
Dependent Claim
22 words
The method of claim 7, wherein said upper surface includes a plurality of arms extending laterally relative to a generally central location.
Claim 10
Dependent Claim
14 words
The method of claim 1, wherein said first material is comprised of silicon nitride.
Claim 11
Dependent Claim
14 words
The method of claim 1, wherein said second material is comprised of silicon dioxide.
Claim 12
Dependent Claim
24 words
The method of claim 1, wherein said first material is comprised of silicon nitride and wherein said second material is comprised of silicon dioxide.
Claim 13
Independent Claim
218 words
A method of fabricating an array of chalcogenide memory cells, comprising the steps of: applying a first layer of dielectric material onto a substrate that includes an array of conductive regions; removing a portion of said first layer of said dielectric material to define an upper surface with generally vertical surfaces extending therefrom to a lower surface in said first layer of said dielectric material, said upper surface being generally horizontal and including a horizontal surface that is generally cross shaped; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said dielectric material, said fixed layer of said second material having a first thickness; applying a second layer of said dielectric material onto said fixed layer of said second material; removing said fixed layer of said second material to define an array of pores in said dielectric material layers, said array of pores generally vertically aligned with said array of conductive regions of said substrate; and providing a chalcogenide memory cell at each of said pores by the steps comprising: applying a layer of chalcogenide material onto a region of said dielectric material layer generally centered at said pore, said layer of chalcogenide material extending into said pore; and applying a layer of conductive material onto said chalcogenide layer.
Claim 14
Independent Claim
218 words
A method of fabricating an array of chalcogenide memory cells, comprising the steps of: applying a first layer of dielectric material onto a substrate that includes an array of conductive regions; removing a portion of said first layer of said dielectric material to define an upper surface with generally vertical surfaces extending therefrom to a lower surface in said first layer of said dielectric material, said upper surface being generally horizontal and including a horizontal surface that is generally cross shaped; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said dielectric material, said fixed layer of said second material having a first thickness; applying a second layer of said dielectric material onto said fixed layer of said second material; removing said fixed layer of said second material to define an array of pores in said dielectric material layers, said array of pores generally vertically aligned with said array of conductive regions of said substrate; and providing a chalcogenide memory cell at each of said pores by the steps comprising: applying a layer of chalcogenide material onto a region of said dielectric material layer generally centered at said pore, said layer of chalcogenide material extending into said pore; and applying a layer of conductive material onto said chalcogenide layer.
Claim 15
Dependent Claim
20 words
The method of claim 12, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms.
Claim 16
Dependent Claim
29 words
The method of claim 12, wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared.
Claim 17
Dependent Claim
45 words
The method of claim 12, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms; and wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared.
Claim 18
Dependent Claim
23 words
The method of claim 12, wherein said cross shaped horizontal upper surface includes a pair of arms extending relative to a central point.
Claim 19
Dependent Claim
24 words
The method of claim 16, wherein said arms of said cross shaped horizontal upper surface range in length from about 0.5 to 1 micron.
Claim 20
Dependent Claim
21 words
The method of claim 12, wherein said upper surface is surrounded by a recess defined in part by said lower surface.
Claim 21
Dependent Claim
22 words
The method of claim 18, wherein said upper surface includes a plurality of arms extending laterally relative to a generally central location.
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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) | 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 |