Patent US6207576B1 successfully refreshed from Google Patents.
US6207576B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-aligned dual damascene arrangement for metal interconnection with low k dielectric constant materials and oxide etch stop layer
Assignee: Advanced Micro Devices Inc
•
Filing: 1999-01-05
•
Granted: 2001-03-27
•
Expires: 2019-01-05
Abstract
Abstract A method of forming a self-aligned dual damascene structure in a semiconductor device arrangement forms a first low k dielectric material over an underlying metal interconnect layer, such as a copper interconnect layer. An oxide etch stop layer is formed on the first low k dielectric layer, and a second low k dielectric layer is formed on the oxide etch stop layer. A trench is etched into the second low k dielectric layer, followed by the etching of a via into the first low k dielectric layer. The first and second low k dielectric materials are different from one another so that they have different sensitivity to at least one etchant chemistry. Undercutting in the second dielectric layer caused by overetching is thereby prevented during the etching of the via in the second dielectric layer by employing an etch chemistry that etches only the first low k dielectric material and not the second low k dielectric material.
Inventors
- 👤 Fei Wang
- 👤 Jerry Cheng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:21
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10W20/084; H10W20/086; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P50/286; H10P50/287; H10P14/00; H10P14/60; H10P14/68; H10P14/683
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
193 words
A method of forming an opening in dielectric interconnect layers in a self-aligned manner, comprising the steps of: forming a first dielectric layer over a conductive layer, the first dielectric layer comprising a first low k dielectric material; forming an oxide layer on the first dielectric layer; patterning the oxide layer to define a first dielectric layer opening pattern; forming a second dielectric layer on the oxide layer, the second dielectric layer comprising a second low k dielectric material having different etch sensitivity than the first low k dielectric material to at least one etchant chemistry; forming a hard mask layer on the second dielectric layer and creating a second dielectric layer opening pattern in the hard mask layer, etching a first opening in the second dielectric layer in accordance with the second dielectric opening pattern in the hard mask layer, wherein the step of etching the first opening includes using a first etchant chemistry that substantially etches only the second dielectric layer; etching a second opening in the first dielectric layer through the first dielectric layer opening pattern in the oxide layer, the first opening at least partially overlapping the second opening.
Claim 2
Independent Claim
193 words
A method of forming an opening in dielectric interconnect layers in a self-aligned manner, comprising the steps of: forming a first dielectric layer over a conductive layer, the first dielectric layer comprising a first low k dielectric material; forming an oxide layer on the first dielectric layer; patterning the oxide layer to define a first dielectric layer opening pattern; forming a second dielectric layer on the oxide layer, the second dielectric layer comprising a second low k dielectric material having different etch sensitivity than the first low k dielectric material to at least one etchant chemistry; forming a hard mask layer on the second dielectric layer and creating a second dielectric layer opening pattern in the hard mask layer, etching a first opening in the second dielectric layer in accordance with the second dielectric opening pattern in the hard mask layer, wherein the step of etching the first opening includes using a first etchant chemistry that substantially etches only the second dielectric layer; etching a second opening in the first dielectric layer through the first dielectric layer opening pattern in the oxide layer, the first opening at least partially overlapping the second opening.
Claim 3
Dependent Claim
25 words
The method of claim 1 , wherein the first low k dielectric material and the second low k dielectric material are polymer based dielectric materials.
Claim 4
Dependent Claim
33 words
The method of claim 2 , wherein the first and second low k dielectric materials are selected from one of benzocyclobutene (BCB) and a low k polymer synthesized from perflourobiphenyl with aromatic bisphenols.
Claim 5
Dependent Claim
33 words
The method of claim 3 , wherein the first low k dielectric material is benzocyclobutene and the second low k dielectric material is a low k polymer synthesized from perflourobiphenyl with aromatic bisphenols.
Claim 6
Dependent Claim
33 words
The method of claim 3 , wherein the first low k dielectric material is a low k polymer synthesized from perflourobinphenyl with aromatic bisphenols and the second low k dielectric material is benzocyclobutene.
Claim 7
Dependent Claim
35 words
The method of claim 1 , wherein the step of etching the second opening includes etching the second opening in the first dielectric layer through the first dielectric layer opening pattern in the oxide layer.
Claim 8
Dependent Claim
33 words
The method of claim 6 , wherein etching the second opening includes using an etchant chemistry that etches only the first dielectric layer so as to substantially avoid etching the second dielectric layer.
Claim 9
Dependent Claim
22 words
The method of claim 7 , wherein the etchant chemistry used to etch the second opening is N 2 /H 2 .
Claim 10
Dependent Claim
16 words
The method of claim 8 , wherein the conductive layer comprises copper or a copper alloy.
Claim 11
Independent Claim
148 words
A method of forming an opening in dielectric interconnect layers in a self-aligned manner, comprising the steps of: forming a first dielectric layer over a conductive layer, the first dielectric layer comprising a first low k dielectric material; forming an oxide layer on the first dielectric layer; patterning the oxide layer to define a first dielectric layer opening pattern; forming a second dielectric layer on the oxide layer, the second dielectric layer comprising a second low k material having different etch sensitivity than the first low k dielectric material to at least one etchant chemistry; etching a first opening in the second dielectric layer using a first etchant chemistry that substantially etches only the second dielectric layer; and etching a second opening in the first dielectric layer through the first dielectric layer opening pattern in the oxide layer, the first opening at least partially overlapping the second opening.
Claim 12
Independent Claim
148 words
A method of forming an opening in dielectric interconnect layers in a self-aligned manner, comprising the steps of: forming a first dielectric layer over a conductive layer, the first dielectric layer comprising a first low k dielectric material; forming an oxide layer on the first dielectric layer; patterning the oxide layer to define a first dielectric layer opening pattern; forming a second dielectric layer on the oxide layer, the second dielectric layer comprising a second low k material having different etch sensitivity than the first low k dielectric material to at least one etchant chemistry; etching a first opening in the second dielectric layer using a first etchant chemistry that substantially etches only the second dielectric layer; and etching a second opening in the first dielectric layer through the first dielectric layer opening pattern in the oxide layer, the first opening at least partially overlapping the second opening.
Claim 13
Dependent Claim
24 words
The method of claim 10 , wherein the first low k dielectric material and the second low k dielectric material are polymer dielectric materials.
Claim 14
Dependent Claim
26 words
The method of claim 10 , further comprising forming a hard mask layer on the second dielectric layer prior to etching the first and second openings.
Claim 15
Dependent Claim
47 words
The method of claim 12 , wherein etching the first opening includes creating a second dielectric layer opening pattern in the hard mask layer and etching the first opening through the second dielectric layer in accordance with the second dielectric opening pattern in the hard mask layer.
Claim 16
Dependent Claim
35 words
The method of claim 13 , wherein the step of etching the second opening includes etching the second opening in the first dielectric layer through the first dielectric layer opening pattern in the oxide layer.
Claim 17
Dependent Claim
36 words
The method of claim 14 , wherein the step of etching the second opening includes using an etchant chemistry that etches only the first dielectric layer so as to substantially avoid etching the second dielectric layer.
Claim 18
Dependent Claim
16 words
The method of claim 15 , wherein the conductive layer comprises copper or a copper alloy.
References Cited (Backward Citations)
US4613888A
Cited
US5374332A
Cited
US5445712A
Cited
US5354712A
Cited
US5508881A
Cited
US5635423A
Cited
US5659201A
Cited
US5705430A
Cited
US5741626A
Cited
US5814557A
Cited
US5693563A
Cited
US5981377A
Cited
US6037664A
Cited
US6013581A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-03-26 | 2004-09-25 | 2005-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-03-26 | 2008-09-25 | 2009-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-03-26 | 2012-09-25 | 2013-03-27 | $7700.00 | Window Closed / Lapsed |