US5416048A
Expired / Lapsed
US
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Method to slope conductor profile prior to dielectric deposition to improve dielectric step-coverage
Assignee: Micron Technology Inc
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Filing: 1993-04-16
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Granted: 1995-05-16
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Expires: 2013-04-16
Abstract
Abstract A process for semiconductor manufacture in which the top corners of conductive features are preferentially etched compared to the etch rate of the vertical and horizontal surfaces, thereby creating a sloped (prograde) profile, i.e., facets. The material removed through the sputter etch process is oxidized and redeposited along the sides of the feature and along the surface of the substrate, thereby improving step coverage when a subsequent dielectric layer is deposited thereon.
Inventors
- 👤 Guy T. Blalock
- 👤 Trung T. Doan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:36
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10P; H10P50/00
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
57 words
A method of forming a sloped profile comprising the following steps of: removing material from a plurality of conductive structures, said structures having sides and corners, said material being removed at a prescribed angle from said corners, said material being redeposited along said sides of said structures adjacent thereto; and converting said redeposited material into an insulator.
Claim 2
Independent Claim
57 words
A method of forming a sloped profile comprising the following steps of: removing material from a plurality of conductive structures, said structures having sides and corners, said material being removed at a prescribed angle from said corners, said material being redeposited along said sides of said structures adjacent thereto; and converting said redeposited material into an insulator.
Claim 3
Dependent Claim
29 words
The method according to claim 1, wherein said removal comprises Reactive Ion Etching (R.I.E.), said etching comprising a plasma, said plasma comprising an inert gas and an oxidizing gas.
Claim 4
Dependent Claim
24 words
The method according to claim 2, wherein said inert gas comprises argon and said oxidizing gas comprises at least one of oxygen and nitrogen.
Claim 5
Dependent Claim
12 words
The method according to claim 3, wherein said conductive structures comprise aluminum.
Claim 6
Dependent Claim
20 words
The method according to claim 4, wherein said conductive structures form at least one of metal lines, interconnects, and leads.
Claim 7
Dependent Claim
17 words
The method according to claim 5, wherein said prescribed angle is in the approximate range of 45°.
Claim 8
Independent Claim
89 words
A method for improving dielectric step-coverage comprising the following steps of: removing material from conductive features disposed on a substrate, said features being disposed in close proximity to one another, said features having corners and sides, said sides forming angles with said substrate, said material being removed at a prescribed angle from said corners and being redeposited in said substrate angles of said proximate features, thereby sloping said angles; and disposing a dielectric layer superjacent said features, said layer blanketing said sloped angles, thereby substantially filling said close proximity.
Claim 9
Independent Claim
89 words
A method for improving dielectric step-coverage comprising the following steps of: removing material from conductive features disposed on a substrate, said features being disposed in close proximity to one another, said features having corners and sides, said sides forming angles with said substrate, said material being removed at a prescribed angle from said corners and being redeposited in said substrate angles of said proximate features, thereby sloping said angles; and disposing a dielectric layer superjacent said features, said layer blanketing said sloped angles, thereby substantially filling said close proximity.
Claim 10
Dependent Claim
26 words
The method according to claim 7, wherein said removal comprises etching said features with a plasma, said plasma comprising a sputtering agent and an oxidizing gas.
Claim 11
Dependent Claim
20 words
The method according to claim 8, wherein said sputtering agent comprises an inert gas, and said oxidizing gas comprises oxygen.
Claim 12
Dependent Claim
23 words
The method according to claim 9, wherein said dielectric comprises at least one of a deposited oxide, silicon nitride, or a polyimide film.
Claim 13
Dependent Claim
22 words
The method according to claim 10, wherein said features comprise at least one of a metal line, an interconnect, and a lead.
Claim 14
Dependent Claim
19 words
The method according to claim 11, wherein said features comprise a metal which forms a stable dielectric upon oxidation.
Claim 15
Dependent Claim
20 words
The method according to claim 8, wherein said sputtering agent comprises an inert gas, and said oxidizing gas comprises nitrogen.
Claim 16
Dependent Claim
97 words
A process for forming a pro-grade profile comprising the following steps of: forward sputtering closely spaced metal features using an inert gas and an oxidizing gas, said forward sputtering forming prescribed angles in said metal features, said feature comprising sides, said sides being substantially normal to a substrate; redepositing material from said forward sputtering along said sides of another of said features and along said substrate, thereby grading said profile of said features, said material being oxidized; and depositing a dielectric superjacent said substrate and said graded profile of said features, said dielectric filling said close space.
Claim 17
Dependent Claim
97 words
A process for forming a pro-grade profile comprising the following steps of: forward sputtering closely spaced metal features using an inert gas and an oxidizing gas, said forward sputtering forming prescribed angles in said metal features, said feature comprising sides, said sides being substantially normal to a substrate; redepositing material from said forward sputtering along said sides of another of said features and along said substrate, thereby grading said profile of said features, said material being oxidized; and depositing a dielectric superjacent said substrate and said graded profile of said features, said dielectric filling said close space.
Claim 18
Dependent Claim
18 words
The process according to claim 14, wherein said sputtering comprises a plasma, said plasma comprising argon and oxygen.
Claim 19
Dependent Claim
16 words
The process according to claim 14, wherein said plasma is generated in a Reactive Ion Etcher.
Claim 20
Dependent Claim
19 words
The process according to claim 16, wherein said features comprise at least one of interconnects, metal lines, and leads.
Claim 21
Dependent Claim
14 words
The process according to claim 17, wherein said dielectric uniformly covers said graded profiles.
Claim 22
Dependent Claim
21 words
The process according to claim 18, wherein said dielectric comprising at least one of a deposited silicon, silicon nitride, and polyimide.
Claim 23
Dependent Claim
25 words
The process according to claim 14, wherein said profile of said features becomes faceted by said sputtering, said facet having an angle of approximately 45°.
References Cited (Backward Citations)
US4125446A
Cited
US4444635A
Cited
US4523372A
Cited
US5089442A
Cited
US5203957A
Cited
US5252520A
Cited
US5344797A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-05-15 | 1998-11-14 | 1999-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-05-15 | 2002-11-14 | 2003-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-05-15 | 2006-11-14 | 2007-05-16 | $7700.00 | Window Closed / Lapsed |