US5202274A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fabricating thin film transistor
Assignee: Samsung Electronics Co Ltd
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Filing: 1991-12-23
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Granted: 1993-04-13
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Expires: 2011-12-23
Abstract
Abstract A method of fabricating a thin film transistor wherein electrode wirings and an insulating layer are fabricated by depositing on a substrate an aluminum alloy layer to become electrode wiring. An Al 2 O 3 layer having a given thickness is then formed by a first anodization of the aluminum alloy layer. Photoresist patterns are then formed that correspond to the electrode wirings on the Al 2 O 3 layer so as to pattern the aluminum alloy layer. The Al 2 O 3 and aluminum alloy layer is then dry-etched to a predetermined depth using the photoresist patterns as a mask. A second anodization is carried out to form the Al 2 O 3 layer up to the surface of the substrate between the electrode wirings, using the photoresist patterns as a mask, whereby the new anodized Al 2 O 3 layer is used as an insulating layer of the electrode wirings.
Inventors
- 👤 Byungseong Bae
- 👤 Insik Jang
- 👤 Namdeog Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:20
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0316; H10D30/0321; H10D64/00; H10D64/01; H10D64/013; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6314; H10P14/6324; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69391
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
144 words
A method of fabricating a thin film transistor comprising the steps of: depositing an aluminum alloy layer on a substrate; forming an Al 2 O 3 layer having a given thickness by anodic oxidation of said aluminum alloy layer; forming photoresist patterns on said Al 2 O 3 layer that correspond to electrode wirings to be formed on the aluminum alloy layer; dry-etching said Al 2 O 3 layer and aluminum alloy layer to a predetermined depth using said photoresist patterns as a mask; and anodically oxidizing said aluminum alloy layer to form a new Al 2 O 3 layer up to the surface of the substrate between the portions of the aluminum layer left to form electrode wirings, using said photoresist patterns as a mask, whereby said new Al 2 O 3 layer is used as an insulating layer of the electrode wirings.
Claim 2
Independent Claim
144 words
A method of fabricating a thin film transistor comprising the steps of: depositing an aluminum alloy layer on a substrate; forming an Al 2 O 3 layer having a given thickness by anodic oxidation of said aluminum alloy layer; forming photoresist patterns on said Al 2 O 3 layer that correspond to electrode wirings to be formed on the aluminum alloy layer; dry-etching said Al 2 O 3 layer and aluminum alloy layer to a predetermined depth using said photoresist patterns as a mask; and anodically oxidizing said aluminum alloy layer to form a new Al 2 O 3 layer up to the surface of the substrate between the portions of the aluminum layer left to form electrode wirings, using said photoresist patterns as a mask, whereby said new Al 2 O 3 layer is used as an insulating layer of the electrode wirings.
Claim 3
Dependent Claim
24 words
A method as recited in claim 1, wherein the aluminum alloy is selected from the group consisting of Al-Si, Al-Pd, Al-Ni, Al-Ge or Al-W.
Claim 4
Dependent Claim
36 words
A method as recited in claim 1, wherein the anodization of the aluminum alloy layer is carried out using the aluminum alloy as an anode, and a stainless steel or a platinum electrode as a cathode.
Claim 5
Dependent Claim
21 words
A method as recited in claim 3, wherein the current density at anodization is between 0.5 to 5 mA/cm 2 .
Claim 6
Dependent Claim
39 words
A method a recited in claim 3, wherein the anodization is carried out with controlled voltage and current in an aqueous solution having 0.01 to 0.5 wt. % of an ammonium tartrate, a tartaric acid, or a citric acid.
Claim 7
Dependent Claim
40 words
A method as recited in claim 1, wherein said Al 2 O 3 layer and aluminum alloy layer are dry-etched by using one from the group consisting of BCl 3 , SiCl 4 , CCl 4 or PCl 3 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-04-12 | 1996-10-12 | 1997-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-12 | 2000-10-12 | 2001-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-12 | 2004-10-12 | 2005-04-13 | $7700.00 | Window Closed / Lapsed |