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US5219782A Expired / Lapsed US ⏱️ 0.0 years remaining

Sublithographic antifuse method for manufacturing

Assignee: Texas Instruments Inc
•
Filing: 1992-03-30
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Granted: 1993-06-15
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Expires: 2012-03-30
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Abstract

Abstract In one described embodiment of the present invention, a method for manufacturing a sublithographic semiconductor feature is disclosed. This method comprises: depositing a feature material on a substrate (14); depositing and patterning a resist material (20) over said feature material; vertically, anisotropically etching said feature material to form a feature pattern (18) with substantially vertical sidewalls underlying said resist material pattern (20); isotropically etching said feature pattern (18) such that said feature pattern (18) sidewalls are undercut from beneath said resist material pattern (20) to form a reduced geometry feature (18) whereby said reduced geometry feature (18) has a geometry less than that of the overlying resist material pattern (20). Another described embodiment comprises an antifuse formed by the above method wherein the antifuse dielectric (24) is a nitride-oxide (N-O) layer. The further advantage gained using this structure is that the programming voltage required is substantially reduced due to the asymmetric current conduction characteristics of the N-O dielectric. This lower programming voltage enhances the scalability of this structure to smaller processes as the need for high voltage transistors is reduced. Other devices, systems and methods are also disclosed.

Inventors

  • 👤 David K.-Y. Liu
  • 👤 Kueing-Long Chen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 18:51
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/49; H10W20/491; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/947

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 83 words
A method for manufacturing a sublithographic semiconductor antifuse, said method comprising: a) depositing a first conductive layer on a substrate; b) depositing and patterning a resist material; c) anisotropically etching said first conductive layer to form a conductive pattern with substantially vertical sidewalls underlying said resist material pattern; e) isotropically etching said conductive pattern such that said conductive pattern sidewalls are undercut from beneath said resist material pattern; f) removing said resist material; and g) depositing an antifuse material overlying said conductive pattern.
Claim 2
Independent Claim 83 words
A method for manufacturing a sublithographic semiconductor antifuse, said method comprising: a) depositing a first conductive layer on a substrate; b) depositing and patterning a resist material; c) anisotropically etching said first conductive layer to form a conductive pattern with substantially vertical sidewalls underlying said resist material pattern; e) isotropically etching said conductive pattern such that said conductive pattern sidewalls are undercut from beneath said resist material pattern; f) removing said resist material; and g) depositing an antifuse material overlying said conductive pattern.
Claim 3
Dependent Claim 20 words
The method of claim 1 and further comprising the step of depositing a second conductive layer over said antifuse material.
Claim 4
Dependent Claim 13 words
The method of claim 2 wherein said second conductive layer is polycrystalline silicon.
Claim 5
Dependent Claim 13 words
The method of claim 2 wherein said second conductive layer is a silicide.
Claim 6
Dependent Claim 41 words
The method of claim 2 and further comprising the step of depositing a sidewall insulator material on sidewalls of said conductive pattern subsequent to said step of removing said resist material and prior to said step of depositing said antifuse material.
Claim 7
Dependent Claim 12 words
The method of claim 5 wherein said sidewall insulator is an oxide.
Claim 8
Dependent Claim 52 words
The method of claim 5 wherein said sidewall insulator is a conformably-deposited oxide layer which has been isotropically etched such that only said oxide layer which lies along the sidewalls of said conductive pattern having a vertical depth greater than the remainder of said oxide layer remains to form said sidewall insulator.
Claim 9
Dependent Claim 13 words
The method of claim 3 wherein said first conductive layer is polycrystalline silicon.
Claim 10
Dependent Claim 13 words
The method of claim 3 wherein said first conductive layer is a silicide.
Claim 11
Dependent Claim 12 words
The method of claim 3 wherein said antifuse material is an oxide.
Claim 12
Dependent Claim 14 words
The method of claim 3 wherein said antifuse material is an asymmetric antifuse material.
Claim 13
Dependent Claim 13 words
The method of claim 3 wherein said antifuse material is a nitride-oxide layer.
Claim 14
Independent Claim 95 words
A method for manufacturing a sublithographic semiconductor antifuse, said method comprising: a) depositing a first conductive layer on a substrate; b) depositing and patterning a resist material; c) anisotropically etching said first conductive layer to form a conductive pattern with substantially vertical sidewalls underlying said resist material pattern; e) isotropically etching said conductive pattern such that said conductive pattern sidewalls are undercut from beneath said resist material pattern; f) removing said resist material; and g) forming a sidewall insulator material on sidewalls of said conductive pattern; h) depositing an antifuse material overlying said conductive pattern.
Claim 15
Independent Claim 95 words
A method for manufacturing a sublithographic semiconductor antifuse, said method comprising: a) depositing a first conductive layer on a substrate; b) depositing and patterning a resist material; c) anisotropically etching said first conductive layer to form a conductive pattern with substantially vertical sidewalls underlying said resist material pattern; e) isotropically etching said conductive pattern such that said conductive pattern sidewalls are undercut from beneath said resist material pattern; f) removing said resist material; and g) forming a sidewall insulator material on sidewalls of said conductive pattern; h) depositing an antifuse material overlying said conductive pattern.
Claim 16
Dependent Claim 20 words
The method of claim 13 and further comprising the step of depositing a second conductive layer over said antifuse material.
Claim 17
Dependent Claim 12 words
The method of claim 13 wherein said sidewall insulator is an oxide.
Claim 18
Dependent Claim 52 words
The method of claim 13 wherein said sidewall insulator is a conformably-deposited oxide layer which has been isotropically etched such that only said oxide layer which lies along the sidewalls of said conductive pattern having a vertical depth greater than the remainder of said oxide layer remains to form said sidewall insulator.

References Cited (Backward Citations)

US4149904A Cited
US4198250A Cited
JPS5691430A Cited
US4329189A Cited
JPS6053052A Cited
JPS61264740A Cited
US4718973A Cited
US4803179A Cited
JPS63131576A Cited
JPS63293967A Cited
US5114873A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-06-14 1996-12-14 1997-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-06-14 2000-12-14 2001-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-06-14 2004-12-14 2005-06-15 $7700.00 Window Closed / Lapsed

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