EP0540261A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Process of removing polymers in semiconductor vias
Assignee: STMicroelectronics lnc USA
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Filing: 1992-10-23
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Granted: —
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Expires: 2012-10-23
Abstract
Abstract A method for forming a contact via (26) in an integrated circuit includes the formation of an aluminum conductive element (20) on an integrated circuit device. A conformal insulating layer (24) is then deposited over the device. Using a masking layer, an anisotropic etch is performed to open a via (26) through the conformal insulating layer (24). During the anisotropic etch, polymers (28) are created from the resist and etch chemistry and adhere to the sidewalls of the via (26). A resist developer containing Tetra Methyl Amonium Hydroxide is used to remove the polymers (28) from the via (26). A contact may now be formed by depositing conductive material (30) into the via (26).
Inventors
- 👤 Loi Ngoc Nguyen
- 👤 Yih-Shung Lin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 20:26
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/20; H10P70/27; H10P70/273; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P70/23; H10P70/234; H10P95/00; H10P95/08; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10W20/083
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
75 words
A method for forming a via, comprising the steps of: forming an insulating layer over a conductive element; forming and patterning a resist layer over the insulating layer to define via locations; anisotropically etching the insulating layer to open vias in the via locations, wherein contaminate particles containing a polymer are formed on the sidewalls of the via; and removing the contaminate particles with a chemical which acts as a developer for the resist layer.
Claim 2
Dependent Claim
13 words
The method of Claim 1, wherein said resist layer comprises a positive resist.
Claim 3
Dependent Claim
18 words
The method of Claim 1, wherein said chemical that acts as a solvent contains Tetra Methyl Amonium Hydroxide.
Claim 4
Dependent Claim
19 words
The method of Claim 3. wherein said chemical which acts as a solvent is a developer for the resist.
Claim 5
Dependent Claim
34 words
The method of Claim 1, wherein a conductive layer is deposited over the device after the contaminate particles are removed, wherein a conductive contact is made between the conductive element and the conductive layer.
Claim 6
Dependent Claim
11 words
The method of Claim 5, wherein said conductive layer comprises aluminum.
Claim 7
Dependent Claim
13 words
A method of Claim 6, wherein said conductive layer comprises a refractory metal.
Claim 8
Dependent Claim
83 words
A structure in an integrated circuit comprising: an interlevel conductive element in an integrated circuit; an insulating layer deposited over the conductive element; a via through the insulating layer, wherein the sidewalls of the via are relatively rough and the upper surface of the conductive layer exposed in the via has a relatively small dip therein; and a second conductive layer over the device and extending into the via, wherein a conductive contact is made between the conductive layer and the conductive element.
Claim 9
Dependent Claim
17 words
The method of Claim 1 or the structure of Claim 8, wherein said conductive element comprises aluminum.
Claim 10
Dependent Claim
19 words
The method of Claim 1 or the structure of Claim 8, wherein said conductive element :omprises a refractory metal.
Claim 11
Dependent Claim
17 words
The method of Claim 1 or the structure of Claim 8, wherein said insulating layer comprises oxide.
Claim 12
Dependent Claim
79 words
The structure of Claim 8, wherein the configuration of the via is the result of: forming the insulating layer over the conductive element; forming and patterning a resist layer over the insulating layer to define via locations; anisotropically etching the insulating layer to form vias at the via locations, wherein contaminate particles containing a polymer are formed on the sidewalls of the via; and removing the contaminate particles with a chemical that acts as a solvent for the resist.
References Cited (Backward Citations)
No citation records indexed.
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