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Patent US5466626A successfully refreshed from Google Patents.
US5466626A
Expired / Lapsed
US
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Micro mask comprising agglomerated material
Assignee: International Business Machines Corp
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Filing: 1993-12-16
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Granted: 1995-11-14
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Expires: 2013-12-16
Abstract
Abstract The subject invention provides a method of forming recesses in a substrate such as a capacitor so as to increase the surface area thereof and therefore the charge storage capacity of the capacitor. This is accomplished by utilizing a micro mask formed by agglomeration on the surface of the substrate. The agglomerated material, such as gold, titanium nitride or titanium silicide, is used as a mask for selectively etching the substrate to form recesses therein. Alternatively, an oxide transfer mask can be utilized with the agglomerated material micro mask to etch the substrate.
Inventors
- 👤 Michael Armacost
- 👤 A. Richard Baker, Jr.
- 👤 Wayne S. Berry
- 👤 Daniel A. Carl
- 👤 Donald M. Kenney
- 👤 Thomas J. Licata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:46
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/01; H10D1/041; H10D1/043; B; B82; B82Y; B82Y10/00; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/033; H10D1/60; H10D1/68; H10D1/692; H10D1/711; H10D1/716; H10P; H10P76/00; H10P76/40; H10P76/405; H10P76/408; H10P76/4088; H10D1/712; Y; Y10; Y10S; Y10S148/00; Y10S148/105; Y10S438/00; Y10S438/942; Y10S438/947; Y10S438/964; Y10S977/00; Y10S977/70; Y10S977/81; Y10S977/84; Y10S977/888
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
59 words
A method of forming recesses in a substrate, said method comprising the steps of: selecting a substrate having a surface thereof; sputter depositing a pattern of agglomerated material, which comprises a compound conductor, on said surface of said substrate; and selectively etching said substrate using said agglomerated material as a mask so as to form recesses in said substrate.
Claim 2
Independent Claim
59 words
A method of forming recesses in a substrate, said method comprising the steps of: selecting a substrate having a surface thereof; sputter depositing a pattern of agglomerated material, which comprises a compound conductor, on said surface of said substrate; and selectively etching said substrate using said agglomerated material as a mask so as to form recesses in said substrate.
Claim 3
Dependent Claim
12 words
The method of claim 1 wherein said substrate comprises a flat capacitor.
Claim 4
Dependent Claim
12 words
The method of claim 1 wherein said substrate comprises a stacked capacitor.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein said substrate comprises a silicon wafer.
Claim 6
Dependent Claim
44 words
The method of claim 1 wherein said substrate comprises a silicon wafer with an insulator layer overlying said silicon wafer, said insulator layer being exposed on an upper surface thereof and said surface of said substrate comprising said upper surface of said insulator layer.
Claim 7
Dependent Claim
54 words
The method of claim 5 wherein said selective etch comprises: first selectively etching said insulator layer using said agglomerated material as a mask so as to form recesses in said insulator layer; and second selectively etching said substrate using said etched insulator layer as a mask so as to form recesses in said substrate.
Claim 8
Dependent Claim
13 words
The method of claim 5 wherein said insulator layer comprises an oxide layer.
Claim 9
Dependent Claim
11 words
The method of claim 7 wherein said oxide comprises silicon dioxide.
Claim 10
Dependent Claim
12 words
The method of claim 1 wherein said pattern comprises a random pattern.
Claim 11
Dependent Claim
12 words
The method of claim 1 wherein said compound conductor comprises titanium nitride.
Claim 12
Dependent Claim
12 words
The method of claim 1 wherein said compound conductor comprises titanium silicide.
Claim 13
Dependent Claim
16 words
The method of claim 1 wherein said selective etch of said substrate comprises reactive ion etching.
Claim 14
Dependent Claim
14 words
The method of claim 1 further comprising removing said agglomerated material from said surface.
Claim 15
Dependent Claim
15 words
The method of claim 13 wherein said agglomerated material is removed during said selective etch.
Claim 16
Dependent Claim
15 words
The method of claim 14 wherein sputtering during said selective etch removes said agglomerated material.
Claim 17
Dependent Claim
15 words
The method of claim 1, wherein the compound conductor is a silicide or a nitride.
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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) | 1998-11-13 | 1999-05-15 | 1999-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-11-13 | 2003-05-15 | 2003-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-11-13 | 2007-05-15 | 2007-11-14 | $7700.00 | Window Closed / Lapsed |