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US5401691A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of fabrication an inverse open frame alignment mark

Assignee: DSS Technology Management Inc
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Filing: 1994-07-01
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Granted: 1995-03-28
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Expires: 2014-07-01
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Abstract

Abstract A method for forming an alignment mark during semiconductor device manufacturing. A first area and a second area are provided on the semiconductor substrate wherein the second area is adjacent to the first area. An alignment mark is formed in the first area. A first layer is formed over the first area and the second area wherein the alignment mark is replicated in the first layer. The first layer is then removed from the second area and left over the first area. A globally planarized second layer, is formed over the first area and the second area. The second layer is then removed from the first area and is left over the second area.

Inventors

  • 👤 Roger F. Caldwell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 03:01
CPC Classifications
H; H10; H10W; H10W46/00; H10W46/501; H10W46/507; Y; Y10; Y10S; Y10S438/00; Y10S438/975

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 149 words
A method for forming an alignment mark on a semiconductor substrate, said method comprising the steps of: forming an alignment mark on said semiconductor substrate, wherein said alignment mark is formed in a first area of said semiconductor substrate, wherein said first area is directly adjacent to a second area of said semiconductor substrate; forming a first layer over said first area and over said second area, wherein said alignment mark is replicated in said first layer; removing a first layer such that said first layer is removed from said second area, and remains over said first area; forming a second layer over said first area and over said second area; planarizing said second layer; and removing said planarized second layer such that said planarized second layer is removed from said first area to uncover said alignment mark formed in said first layer, and remains over said second area.
Claim 2
Independent Claim 149 words
A method for forming an alignment mark on a semiconductor substrate, said method comprising the steps of: forming an alignment mark on said semiconductor substrate, wherein said alignment mark is formed in a first area of said semiconductor substrate, wherein said first area is directly adjacent to a second area of said semiconductor substrate; forming a first layer over said first area and over said second area, wherein said alignment mark is replicated in said first layer; removing a first layer such that said first layer is removed from said second area, and remains over said first area; forming a second layer over said first area and over said second area; planarizing said second layer; and removing said planarized second layer such that said planarized second layer is removed from said first area to uncover said alignment mark formed in said first layer, and remains over said second area.
Claim 3
Independent Claim 43 words
A method of claim i further comprising the step of forming a third layer such that said third layer is formed over said first area and replicates said alignment mark and such that said third layer does not form in said second area.
Claim 4
Dependent Claim 61 words
The method of claim 2 further comprising the step of: forming a fourth layer over said first area and over said second and above said first and second layer, wherein said alignment mark is replicated in said fourth layer; and removing said fourth layer such that said fourth layer is removed from said second area and remains over said first area.
Claim 5
Dependent Claim 73 words
The method of claim 3 further comprising the steps of: forming a fifth layer over said first area and said second area and above said first layer and said second layer; planarizing said fifth layer such that said alignment mark is not replicated in said planarized fifth layer; removing said fifth layer from said first area such that said alignment mark in said first layer is revealed; and remains over said second area.
Claim 6
Dependent Claim 20 words
The method of claim 1 wherein said first layer is a polysilicon layer and said second layer comprises silicon dioxide.
Claim 7
Dependent Claim 11 words
The method of claim 5 wherein said second layer comprises BPSG.
Claim 8
Dependent Claim 14 words
The method of claim 2 wherein said third layer is a grown oxide layer.
Claim 9
Dependent Claim 13 words
The method of claim 3 wherein said fourth layer is a metal layer.
Claim 10
Dependent Claim 11 words
The method of claim 8 wherein said fourth layer comprises aluminum.
Claim 11
Dependent Claim 12 words
The method of claim 4 wherein said fifth layer comprises silicon dioxide.
Claim 12
Independent Claim 202 words
A method for forming an alignment mark on a semiconductor substrate, said method comprising the steps of: forming an alignment mark on said semiconductor substrate, wherein said alignment mark is formed in a first area of said semiconductor substrate, wherein said first area is directly adjacent to a second area of said semiconductor substrate; growing an oxide layer such that said oxide layer is grown over said first area and substantially replicates said alignment mark and such that said oxide is not grown over said second area; depositing a polysilicon layer over said first area and said second area, wherein said alignment mark is replicated in said polysilicon area; etching said polysilicon layer such that said polysilicon layer is removed from said second area and remains over said first area; depositing a first insulating layer comprising silicon dioxide over said first area and said second area; planarizing said first insulating layer by chemical-mechanical polishing such that said alignment mark is not substantially replicated in said first insulating layer; and etching said first insulating layer such that said first insulating layer is removed from said first area to reveal said alignment mark replicated in said polysilicon layer, and remains over said second area.
Claim 13
Independent Claim 202 words
A method for forming an alignment mark on a semiconductor substrate, said method comprising the steps of: forming an alignment mark on said semiconductor substrate, wherein said alignment mark is formed in a first area of said semiconductor substrate, wherein said first area is directly adjacent to a second area of said semiconductor substrate; growing an oxide layer such that said oxide layer is grown over said first area and substantially replicates said alignment mark and such that said oxide is not grown over said second area; depositing a polysilicon layer over said first area and said second area, wherein said alignment mark is replicated in said polysilicon area; etching said polysilicon layer such that said polysilicon layer is removed from said second area and remains over said first area; depositing a first insulating layer comprising silicon dioxide over said first area and said second area; planarizing said first insulating layer by chemical-mechanical polishing such that said alignment mark is not substantially replicated in said first insulating layer; and etching said first insulating layer such that said first insulating layer is removed from said first area to reveal said alignment mark replicated in said polysilicon layer, and remains over said second area.
Claim 14
Dependent Claim 58 words
The method of claim 11 further comprising the steps of: depositing a first metal layer over said first area and said second area, such that said alignment mark is replicated in said first metal layer; etching said first metal layer such that said first metal layer is removed from said second area and remains in said first area.
Claim 15
Dependent Claim 83 words
The method of claim 12 further comprising the steps of: depositing a second insulating layer over said first area and said second area; planarizing said second insulating layer by chemical-mechanical polishing such that said alignment mark is not replicated in said planarized second insulating layer; and etching said planarized second insulating layer such that said planarized second insulating layer is removed from said first area to reveal said alignment mark replicated in said first metal layer, and said remains over said second area.
Claim 16
Dependent Claim 23 words
The method of claim 13 further comprising the steps of forming a metal layer over said first area and over said second area.

References Cited (Backward Citations)

US4125418A Cited
US4632724A Cited
US5298110A Cited
US5332470A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-03-27 1998-09-26 1999-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-03-27 2002-09-26 2003-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-03-27 2006-09-26 2007-03-28 $7700.00 Window Closed / Lapsed

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