Patent US5989784A successfully refreshed from Google Patents.
US5989784A
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Etch recipe for embedded DRAM passivation with etch stopping layer scheme
Assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
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Filing: 1998-04-06
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Granted: 1999-11-23
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Expires: 2018-04-06
Abstract
Abstract A method of forming an etch stop layer 40 above a fuse 16 in a fuse opening (or window) 92 using a specialized 2 stage etch process. The invention has two important features: First, the etch stop layer 40 is formed from a polysilicon layer (P2 or P4) that is used to fabricate semiconductor devices on a substrate. The etch stop layer 40 is preferably formed of polysilicon layer to is used to from a contact to the substrate 10 (P2) or to form part of a capacitor (P4). Second, a specialized two stage etch process is used where the second stage etches the etch stop layer 40 while simultaneously forming a passivation layer 114 over a metal pad 85. The method comprises: forming fuses 16 over said isolation regions 10 over the fuse area 15; forming a first dielectric layer 30 overlying the fuses 16; forming an etch stop layer 40 over the first dielectric layer 30; forming an insulating layer 43 over the etch stop layer; forming a fuse opening 92 in the insulating layer 43 by etching, in a first etch stage, thorough fuse photoresist openings 90A and stopping the first etch stage on the etch stop layer 40; and etching though the etch stop layer 40 in the fuse opening 92 in a second etch stage.
Inventors
- 👤 Yu-Hua Lee
- 👤 Cheng-Ming Wu
- 👤 Chao-Cheng Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:49
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/49; H10W20/493; H10W20/494; H10W20/01; H10W20/071; H10W20/081
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
130 words
The method of forming a fuse opening using an etch stop layer comprising: (1a) forming isolation regions defining a fuse area and active areas on a substrate; (1b) forming fuses over said isolation regions over said fuse area; (1c) forming a first dielectric layer overlying said fuses; (1d) forming an etch stop layer over said first dielectric layer; (1e) forming an insulating layer over said etch stop layer; (1f) forming a first photoresist layer having fuse photoresist openings over said fuse area; (1g) forming a fuse opening in said insulating layer by etching, in a first etch stage, thorough said fuse photoresist openings and stopping the first etch stage on said etch stop layer; (1h) etching though said etch stop layer in said fuse opening in a second etch stage.
Claim 2
Independent Claim
130 words
The method of forming a fuse opening using an etch stop layer comprising: (1a) forming isolation regions defining a fuse area and active areas on a substrate; (1b) forming fuses over said isolation regions over said fuse area; (1c) forming a first dielectric layer overlying said fuses; (1d) forming an etch stop layer over said first dielectric layer; (1e) forming an insulating layer over said etch stop layer; (1f) forming a first photoresist layer having fuse photoresist openings over said fuse area; (1g) forming a fuse opening in said insulating layer by etching, in a first etch stage, thorough said fuse photoresist openings and stopping the first etch stage on said etch stop layer; (1h) etching though said etch stop layer in said fuse opening in a second etch stage.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein said first dielectric layer has a thickness in a range of between about 1000 and 3000 Å.
Claim 4
Dependent Claim
42 words
The method of claim 1 wherein said etch stop layer is composed of a material selected from the group consisting of polysilicon and polycide; and said etch stop layer having a thickness in a range of between about 500 and 3000 Å.
Claim 5
Dependent Claim
27 words
The method of claim 1 wherein said etch stop layer is formed from a polysilicon layer that comprises a contact to said substrate in said active area.
Claim 6
Dependent Claim
29 words
The method of claim 1 wherein said etch stop layer is formed from a polysilicon layer that also forms a Top electrode of a capacitor over said active area.
Claim 7
Dependent Claim
36 words
The method of claim 1 wherein said insulating layer comprised of a plurality of inter metal dielectric layers composed of oxide and having a total thickness in a range of between about 6 and 7 μm.
Claim 8
Dependent Claim
29 words
The method of claim 1 wherein the etching of said fuse opening performed with a gas mixture comprised of SF 6 , Ar, CHF 3 and CF 4 .
Claim 9
Dependent Claim
62 words
The method of claim 1 wherein said first etch stage consists of two etch steps, a first etch step and a second etch step; said first etch step uses a gas mixture comprised of SF 6 , Ar, CHF 3 and CF 4 ; and said second etch step uses a gas mixture consisting of Ar, CHF 3 and CF 4 .
Claim 10
Dependent Claim
19 words
The method of claim 1 wherein step (1h) further includes forming a top passivation layer over a metal pad.
Claim 11
Dependent Claim
48 words
The method of claim 1 wherein step (1h) further includes etching through said etch stop layer in said second etch stage performed using gas mixture comprised of a F containing gas and a Chloride containing gas; and over etching into said first dielectric layer less than 300 Å.
Claim 12
Dependent Claim
51 words
The method of claim 1 wherein step (1h) further includes etching through said etch stop layer in said second etch stage performed using gas mixture comprised of a SF 6 , CHF 3 , CF 4 , and Ar; and over etching into said first dielectric layer less than 300 Å.
Claim 13
Independent Claim
223 words
The method of forming a fuse opening using an etch stop layer comprising: (12a) forming isolation regions defining a fuse area and active areas on a substrate; (12b) forming fuses over said isolation regions over said fuse area; (12c) forming a first dielectric layer overlying said fuses; (12d) forming an etch stop layer over said first dielectric layer; (12e) forming an insulating layer over said etch stop layer; (12f) forming a top metal layer and a metal pad over said insulating layer; (12g) forming a top passivation layer over said top metal layer and said insulating layer; (12h) forming a first photoresist layer having fuse photoresist openings over said fuse area, and having an photoresist pad opening over said metal pad; (12i) forming a fuse opening in said insulating layer by etching, in a first etch stage, thorough said fuse photoresist openings and stopping the first etch stage on said etch stop layer; (1) said first etch stage consists of a first etch step and a second etch step; said first etch step uses a gas mixture comprised of SF 6 , Ar, CHF 3 and CF 4 ; and said second etch step uses a gas mixture consisting of Ar, CHF 3 and CF 4 ; (12j) etching though said etch stop layer in said fuse opening in a second etch stage.
Claim 14
Independent Claim
223 words
The method of forming a fuse opening using an etch stop layer comprising: (12a) forming isolation regions defining a fuse area and active areas on a substrate; (12b) forming fuses over said isolation regions over said fuse area; (12c) forming a first dielectric layer overlying said fuses; (12d) forming an etch stop layer over said first dielectric layer; (12e) forming an insulating layer over said etch stop layer; (12f) forming a top metal layer and a metal pad over said insulating layer; (12g) forming a top passivation layer over said top metal layer and said insulating layer; (12h) forming a first photoresist layer having fuse photoresist openings over said fuse area, and having an photoresist pad opening over said metal pad; (12i) forming a fuse opening in said insulating layer by etching, in a first etch stage, thorough said fuse photoresist openings and stopping the first etch stage on said etch stop layer; (1) said first etch stage consists of a first etch step and a second etch step; said first etch step uses a gas mixture comprised of SF 6 , Ar, CHF 3 and CF 4 ; and said second etch step uses a gas mixture consisting of Ar, CHF 3 and CF 4 ; (12j) etching though said etch stop layer in said fuse opening in a second etch stage.
Claim 15
Dependent Claim
27 words
The method of claim 12 wherein said etch stop layer is formed from a polysilicon layer that comprises a contact to said substrate in said active area.
Claim 16
Dependent Claim
29 words
The method of claim 12 wherein said etch stop layer is formed from a polysilicon layer that also forms a top electrode of a capacitor over said active area.
Claim 17
Dependent Claim
42 words
The method of claim 12 wherein step (12i) said first etch stage further includes etching said top passivation layer exposing said top metal pad, and wherein step (12j) said second etch stage further includes forming a passivation layer over said metal pad.
Claim 18
Dependent Claim
36 words
The method of claim 12 wherein step (12j) further includes etching through said etch stop layer in said second etch stage performed using gas mixture comprised of a F containing gas and a Chloride containing gas.
Claim 19
Dependent Claim
51 words
The method of claim 12 wherein step (12j) further includes etching through said etch stop layer in said second etch stage performed using gas mixture comprised of a SF 6 , CHF 3 , CF 4 , and Ar; and over etching into said first dielectric layer less than 300 Å.
Claim 20
Independent Claim
229 words
A method of forming a fuse opening using an etch stop layer and a pad opening and a specialized two stage etch process comprising: (18a) forming isolation regions defining a fuse area and active areas on a substrate; (18b) forming fuses over said isolation regions over said fuse area; (18c) forming a first dielectric layer overlying said fuses; (18d) forming an etch stop layer over said first dielectric layer; (18e) forming an first insulating layer over said etch stop layer; (18f) forming a plurality of metal layers, spaced apart by a plurality of inter metal dielectric layers over said insulating layer; said plurality of metal layers having a top metal layer and a metal pad formed from said top metal layer; (18g) forming a top passivation layer over said top metal layer and said insulating layer; (18h) forming a first photoresist layer having fuse photoresist openings over said fuse area and a photoresist pad opening over said metal pad; (18i) etching, in a first etch stage, a fuse opening thorough said fuse photoresist openings in said top passivation layer, said plurality of inter metal dielectric layers, and said insulating layer; and etching a pad opening in said top passivation layer exposing said metal pad; (18j) etching, in a second etch stage, though said etch stop layer in said fuse opening and forming a passivation layer over said metal pad.
Claim 21
Independent Claim
229 words
A method of forming a fuse opening using an etch stop layer and a pad opening and a specialized two stage etch process comprising: (18a) forming isolation regions defining a fuse area and active areas on a substrate; (18b) forming fuses over said isolation regions over said fuse area; (18c) forming a first dielectric layer overlying said fuses; (18d) forming an etch stop layer over said first dielectric layer; (18e) forming an first insulating layer over said etch stop layer; (18f) forming a plurality of metal layers, spaced apart by a plurality of inter metal dielectric layers over said insulating layer; said plurality of metal layers having a top metal layer and a metal pad formed from said top metal layer; (18g) forming a top passivation layer over said top metal layer and said insulating layer; (18h) forming a first photoresist layer having fuse photoresist openings over said fuse area and a photoresist pad opening over said metal pad; (18i) etching, in a first etch stage, a fuse opening thorough said fuse photoresist openings in said top passivation layer, said plurality of inter metal dielectric layers, and said insulating layer; and etching a pad opening in said top passivation layer exposing said metal pad; (18j) etching, in a second etch stage, though said etch stop layer in said fuse opening and forming a passivation layer over said metal pad.
Claim 22
Dependent Claim
42 words
The method of claim 18 wherein said etch stop layer is composed of a material selected from the group consisting of polysilicon and polycide; and said etch stop layer having a thickness in a range of between about 500 and 3000 Å.
Claim 23
Dependent Claim
28 words
The method of claim 18 wherein said etch stop layer is formed from a polysilicon layer (p2) that comprises a contact to said substrate in said active area.
Claim 24
Dependent Claim
30 words
The method of claim 18 wherein said etch stop layer is formed from a polysilicon layer (p4) that also forms a Top electrode of a capacitor over said active area.
Claim 25
Dependent Claim
62 words
The method of claim 18 wherein said first etch stage consists of two etch steps, a first etch step and a second etch step; said first etch step uses a gas mixture comprised of SF 6 , Ar, CHF 3 and CF 4 ; and said second etch step uses a gas mixture consisting of Ar, CHF 3 and CF 4 .
Claim 26
Dependent Claim
36 words
The method of claim 18 wherein step (18i) further includes etching through said etch stop layer in said second etch stage performed using gas mixture comprised of a F containing gas and a Chloride containing gas.
Claim 27
Dependent Claim
39 words
The method of claim 18 wherein step (18j) further includes etching through said etch stop layer in said second etch stage performed using gas mixture comprised of a SF 6 , CHF 3 , CF 4 , and Ar.
References Cited (Backward Citations)
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