US5240868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabrication metal-electrode in semiconductor device
Assignee: Samsung Electronics Co Ltd
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Filing: 1991-12-20
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Granted: 1993-08-31
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Expires: 2011-12-20
Abstract
Abstract A method of fabricating a metal electrode of a semiconductor device that includes a substrate with unanodized and anodized metal layers thereon includes the steps of forming a first metal layer, which is anodizable, to a first predetermined thickness on a substrate; forming and patterning a second metal layer, which is not anodizable, to a second predetermined thickness so as to act as a mask on the first metal layer; depositing a third metal layer, that may be anodizable, to a third predetermined thickness; and forming a flat surface on the third layer by anodic oxidation. Various preferred embodiments and relationships between thickness of each layer for flattening by anodic oxidation are also given.
Inventors
- 👤 Byungseong Bae
- 👤 Jeongha Sohn
- 👤 Insik Jang
- 👤 Sangsoo Kim
- 👤 Namdeog Kim
- 👤 Hyungtaek Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:58
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/069; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0316; H10D30/0321; H10D30/60; H10D30/67; H10D30/6704; H10D30/6725; H10D30/6729; H10D30/6737; H10D30/6739; H10D64/00; H10D64/01; H10D64/013; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6314; H10W20/071; H10W20/092; H10P14/6324
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
102 words
A method of fabricating a metal electrode of a semiconductor device comprising the steps of: forming a first metal layer, which is anodizable, to a first predetermined thickness on a substrate; forming and patterning a second metal layer, which is not anodizable, to a second predetermined thickness so as to act as a mask on said first metal layer; depositing a third metal layer, that may be anodizable, to a third predetermined thickness and having a nonflat surface; and flattening the surface of the third layer by anodic oxidation of the first and third layers using the second layer as a mask.
Claim 2
Independent Claim
102 words
A method of fabricating a metal electrode of a semiconductor device comprising the steps of: forming a first metal layer, which is anodizable, to a first predetermined thickness on a substrate; forming and patterning a second metal layer, which is not anodizable, to a second predetermined thickness so as to act as a mask on said first metal layer; depositing a third metal layer, that may be anodizable, to a third predetermined thickness and having a nonflat surface; and flattening the surface of the third layer by anodic oxidation of the first and third layers using the second layer as a mask.
Claim 3
Dependent Claim
24 words
A method as recited in claim 1, wherein the thickness of said third metal layer is equal to that of the first metal layer.
Claim 4
Dependent Claim
67 words
A method as recited in claim 1, wherein the thicknesses of the first metal layer and second metal layer are respectively designated with d 1 and d 2 , and the variation rate of thickness of the first metal layer by anodic oxidation is designed A, further comprising controlling the thickness d 2 of the second metal layer to satisfy the formulae: d 2 =(A-1)d 1 .
Claim 5
Dependent Claim
37 words
A method as recited in claim 1, wherein said first metal layer is selected from the group consisting of Ta and Al, and said second metal layer is selected from the group consisting of Cu and Cr.
Claim 6
Dependent Claim
51 words
A method as recited in claim 1 wherein said process is applied to any one of a thin film transistor of reverse staggered type or a thin film transistor of staggered type, and the manufacturing stage of a semiconductor device having a metal pattern with step-like difference between layers for flattening.
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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) | 1996-08-30 | 1997-03-01 | 1997-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-30 | 2001-03-01 | 2001-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-30 | 2005-03-01 | 2005-08-31 | $7700.00 | Window Closed / Lapsed |