US5990002A
Expired / Lapsed
US
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Method of making an antireflective structure
Assignee: Micron Technology Inc
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Filing: 1998-05-21
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Granted: 1999-11-23
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Expires: 2018-05-21
Abstract
Abstract Inventive antireflective structures comprise a semiconductor substrate having hereon a combination of a plurality of layers that either that absorb reflected light or that dissipate reflected light into patterns and intensities that do not substantially alter photoresist material on the semiconductor substrate. The semiconductor substrate has formed thereon a feature having a width of less than about 0.25 microns. Antireflective structures contemplated include a first layer of polysilicon and first layer of silicon nitride material that is formed upon the first layer of polysilicon. The antireflective structure has the ability to scatter unabsorbed light into patterns and intensities that are substantially ineffective to alter photoresist material exposed to said patterns and intensities. A first antireflective structure comprises a first layer of polysilicon disposed upon on a semiconductor substrate, a second layer of silicon nitride material disposed upon the first layer of polysilicon, and a masking layer disposed upon the second layer of silicon nitride material. A second antireflective structure comprises a first layer of polysilicon disposed upon on a semiconductor substrate, a first layer of nitride material disposed upon the first layer of polysilicon, a second layer of polysilicon disposed upon the first layer of silicon nitride material, and a masking layer disposed upon the second layer of polysilicon. A third antireflective structure comprises a first layer of polysilicon disposed upon on a semiconductor substrate, a first layer of silicon nitride material disposed upon the first layer of polysilicon, a second layer of polysilicon disposed upon the first layer of silicon nitride material, a second layer of silicon nitride material disposed upon the second layer of polysilicon, and a masking layer disposed upon the second layer of silicon nitride material.
Inventors
- 👤 Ardavan Niroomand
- 👤 Fernando Gonzalez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:56
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091; H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/014; H10W10/10; H10W10/17; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/952; Y10S438/964
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
115 words
A method of forming a submicron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å; forming a second layer substantially composed of a nitride material, disposed substantially conformably upon said first layer, said second layer material having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer.
Claim 2
Independent Claim
115 words
A method of forming a submicron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å; forming a second layer substantially composed of a nitride material, disposed substantially conformably upon said first layer, said second layer material having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer.
Claim 3
Dependent Claim
145 words
The method as defined in claim 1, wherein said first and second points on said second layer are separated a width of less than about 0.25 microns and are adjacent to a mask structure that is at least one of: a portion of said photoresist layer upon said second layer that: projects from said second layer; and extends continuously between the first and second points on said second layer; and primary and secondary portions of said photoresist layer that project from said second layer, wherein the primary portion of the photoresist layer is adjacent to the first point on the second layer and the secondary portion of the photoresist layer is adjacent to the second point on the second layer, and wherein the second layer is substantially continuously uncovered by said photoresist layer between the first and second points so as to be substantially exposed.
Claim 4
Dependent Claim
14 words
The method as defined in claim 1, wherein said second layer comprises silicon nitride.
Claim 5
Dependent Claim
27 words
The method as defined in claim 1, wherein said second layer comprises Si x N where x is in a range from greater than 0.75 to 10.
Claim 6
Dependent Claim
70 words
The method as defined in claim 1, wherein a feature surface on said second layer extends between the first and second points, the method further comprising defining under said feature surface a patterned space having a width not greater than that of the feature surface, said patterned space being selected from the group consisting of a contact hole, a via, a wiring trench, an active area and an isolation trench.
Claim 7
Dependent Claim
26 words
The method as defined in claim 1, wherein said second layer includes a layer of polysilicon upon which said at least one mask structure is situated.
Claim 8
Dependent Claim
39 words
The method as defined in claim 1, wherein said second layer includes a layer of polysilicon, wherein a nitride material is formed above said layer of polysilicon, and wherein said layer of photoresist is situated upon said nitride material.
Claim 9
Dependent Claim
118 words
The method as defined in claim 1, wherein a feature surface on said second layer extends between the first and second points, the method further comprising: forming a recess under said feature surface in said first layer, said second layer, and said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; and forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material.
Claim 10
Dependent Claim
32 words
The method as defined in claim 8, further comprising: forming a secondary layer upon said primary layer, said secondary layer being selected from the group consisting of polysilicon and a nitride material.
Claim 11
Dependent Claim
28 words
The method as defined in claim 1, wherein forming the second layer is by a method selected from the group consisting of CVD and thermal transformation of polysilicon.
Claim 12
Dependent Claim
64 words
The method as defined in claim 1, wherein forming and patterning the layer of photoresist upon said second layer to expose first and second points on said second layer comprises exposing said photoresist layer to an incident patterning light, and wherein the first and second layer have a combined reflectivity to said incident patterning light of less than about 10% of incident patterning light.
Claim 13
Dependent Claim
77 words
The method as defined in to claim 1, wherein said at least one polysilicon layer is formed so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer.
Claim 14
Independent Claim
253 words
A method of forming a submicron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å; forming a second layer substantially composed of a nitride material, disposed substantially conformably upon said first layer, said second layer having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer, wherein said first and second points on said second layer are separated by a width of less than about 0.25 microns and are adjacent to a mask structure that is at least one of: a portion of said photoresist layer upon said second layer that: projects from said second layer; and extends continuously between the first and second points on said second layer; and primary and secondary portions of said photoresist layer that project from said second layer, wherein the primary portion of the photoresist layer is adjacent to the first point on the second layer and the secondary portion of the photoresist layer is adjacent to the second point on the second layer, and wherein the second layer is substantially continuously uncovered by said photoresist layer between the first and second points so as to be substantially exposed.
Claim 15
Independent Claim
253 words
A method of forming a submicron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å; forming a second layer substantially composed of a nitride material, disposed substantially conformably upon said first layer, said second layer having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer, wherein said first and second points on said second layer are separated by a width of less than about 0.25 microns and are adjacent to a mask structure that is at least one of: a portion of said photoresist layer upon said second layer that: projects from said second layer; and extends continuously between the first and second points on said second layer; and primary and secondary portions of said photoresist layer that project from said second layer, wherein the primary portion of the photoresist layer is adjacent to the first point on the second layer and the secondary portion of the photoresist layer is adjacent to the second point on the second layer, and wherein the second layer is substantially continuously uncovered by said photoresist layer between the first and second points so as to be substantially exposed.
Claim 16
Dependent Claim
14 words
The method as defined in claim 13, wherein said second layer comprises silicon nitride.
Claim 17
Dependent Claim
27 words
The method as defined in claim 13, wherein said second layer comprises Si x N where x is in a range from greater than 0.75 to 10.
Claim 18
Dependent Claim
24 words
The method as defined in claim 13, wherein said second layer includes a layer of polysilicon upon which said layer of photoresist is situated.
Claim 19
Dependent Claim
39 words
The method as defined in claim 13, wherein said second layer includes a layer of polysilicon, wherein a nitride material is formed above said layer of polysilicon, and wherein said layer of photoresist is situated upon said nitride material.
Claim 20
Dependent Claim
118 words
The method as defined in claim 13, wherein a feature surface on said second layer extends between the first and second points, the method further comprising: forming a recess under said feature surface in said first layer, said second layer, and said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; and forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material.
Claim 21
Dependent Claim
32 words
The method as defined in claim 18, further comprising: forming a secondary layer upon said primary layer, said secondary layer being selected from the group consisting of polysilicon and a nitride material.
Claim 22
Independent Claim
214 words
A method of forming a submicron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å and being formed: so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer; forming a second layer substantially composed of a nitride material, disposed substantially conformably upon said first layer, said second layer having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer so as to expose said photoresist layer to an incident patterning light, and wherein the first and second layer have a combined reflectivity to said incident patterning light of less than about 10% of incident patterning light.
Claim 23
Independent Claim
214 words
A method of forming a submicron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å and being formed: so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer; forming a second layer substantially composed of a nitride material, disposed substantially conformably upon said first layer, said second layer having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer so as to expose said photoresist layer to an incident patterning light, and wherein the first and second layer have a combined reflectivity to said incident patterning light of less than about 10% of incident patterning light.
Claim 24
Dependent Claim
118 words
The method as defined in claim 20, wherein a feature surface on said second layer extends between the first and second points, the method further comprising: forming a recess under said feature surface in said first layer, said second layer, and said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; and forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material.
Claim 25
Dependent Claim
32 words
The method as defined in claim 21, further comprising: forming a secondary layer upon said primary layer, said secondary layer being selected from the group consisting of polysilicon and a nitride material.
Claim 26
Dependent Claim
28 words
The method as defined in claim 20, wherein forming the second layer is by a method selected from the group consisting of CVD and thermal transformation of polysilicon.
Claim 27
Dependent Claim
70 words
The method as defined in claim 20, wherein a feature surface on said second layer extends between the first and second points, the method further comprising defining under said feature surface a patterned space having a width not greater than that of the feature surface, said patterned space being selected from the group consisting of a contact hole, a via, a wiring trench, an active area and an isolation trench.
Claim 28
Dependent Claim
26 words
The method as defined in claim 20, wherein said second layer includes a layer of polysilicon upon which said at least one mask structure is situated.
Claim 29
Dependent Claim
41 words
The method as defined in claim 20, wherein said second layer includes a layer of polysilicon, wherein a nitride material is formed above said layer of polysilicon, and wherein said layer of photoresist is situated upon said layer of nitride material.
Claim 30
Independent Claim
451 words
A method of forming a sub-micron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å, wherein said at least one polysilicon layer is formed so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer; forming a second layer disposed substantially conformably upon said first layer, said second layer having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer, wherein a feature surface on said second layer extends to terminate at the first and second points, wherein said first and second points on said second layer are separated by a width of less than about 0.25 microns and are adjacent to a mask structure that is at least one of: a portion of said photoresist layer upon said second layer that: projects from said second layer; and extends continuously between the first and second points on said second layer; and primary and secondary portions of said photoresist layer that project from said second layer, wherein the primary portion of the photoresist layer is adjacent to the first point on the second layer and the secondary portion of the photoresist layer is adjacent to the second point on the second layer, and wherein the second layer is substantially continuously uncovered by said photoresist layer between the first and second points so as to be substantially exposed forming a recess under said feature surface in said first layer, within said second layer, and within said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material; and forming a nitride material upon said primary layer by a method selected from the group consisting of CVD and thermal transformation of polysilicon material.
Claim 31
Independent Claim
451 words
A method of forming a sub-micron surface on a structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å, wherein said at least one polysilicon layer is formed so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer; forming a second layer disposed substantially conformably upon said first layer, said second layer having a thickness in a range from about 200 Å to about 1,000 Å; and forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer, wherein a feature surface on said second layer extends to terminate at the first and second points, wherein said first and second points on said second layer are separated by a width of less than about 0.25 microns and are adjacent to a mask structure that is at least one of: a portion of said photoresist layer upon said second layer that: projects from said second layer; and extends continuously between the first and second points on said second layer; and primary and secondary portions of said photoresist layer that project from said second layer, wherein the primary portion of the photoresist layer is adjacent to the first point on the second layer and the secondary portion of the photoresist layer is adjacent to the second point on the second layer, and wherein the second layer is substantially continuously uncovered by said photoresist layer between the first and second points so as to be substantially exposed forming a recess under said feature surface in said first layer, within said second layer, and within said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material; and forming a nitride material upon said primary layer by a method selected from the group consisting of CVD and thermal transformation of polysilicon material.
Claim 32
Independent Claim
401 words
A method of an antireflective structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å and being formed so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer; forming a second layer disposed substantially conformably upon said first layer, said second layer: having a thickness in a range from about 200 Å to about 1,000 Å, having a feature surface on said second layer extends between the first and second points, there being defined under said feature surface a patterned space having a width not greater than that of the feature surface, said patterned space being selected from the group consisting of a contact hole, a via, a wiring trench, an active area and an isolation trench; and being formed of a nitride material by a process selected from the group consisting of CVD and thermal transformation of polysilicon; forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer so as to expose said photoresist layer to an incident patterning light, and wherein the first and second layer have a combined reflectivity to said incident patterning light of less than about 10% of incident patterning light; forming a recess under said feature surface in said first layer, said second layer, and said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; and forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material; forming a secondary layer upon said primary layer, said secondary layer being selected from the group consisting of polysilicon and a nitride material.
Claim 33
Independent Claim
401 words
A method of an antireflective structure comprising: forming a first layer on a semiconductor substrate, said first layer including at least one polysilicon layer, said at least one polysilicon layer having a thickness of less than about 500 Å and a grain size in a range from about 500 Å to about 2,500 Å and being formed so as to have said grain size by a process selected from the group consisting of heat treatment of said at least one polysilicon layer, etching a surface upon said semiconductor substrate prior to formation of said at least one polysilicon layer, and flashing of entrapped undisassociated CVD feed material in a deposition of said at least one polysilicon layer; forming a second layer disposed substantially conformably upon said first layer, said second layer: having a thickness in a range from about 200 Å to about 1,000 Å, having a feature surface on said second layer extends between the first and second points, there being defined under said feature surface a patterned space having a width not greater than that of the feature surface, said patterned space being selected from the group consisting of a contact hole, a via, a wiring trench, an active area and an isolation trench; and being formed of a nitride material by a process selected from the group consisting of CVD and thermal transformation of polysilicon; forming and patterning a layer of photoresist upon said second layer to expose first and second points on said second layer so as to expose said photoresist layer to an incident patterning light, and wherein the first and second layer have a combined reflectivity to said incident patterning light of less than about 10% of incident patterning light; forming a recess under said feature surface in said first layer, said second layer, and said semiconductor substrate having a width less than or equal to that of said feature surface; filling said recess with a dielectric material; removing substantially all material above an upper level of said recess to form a substantially planar surface including substantially co-planar surfaces on said first layer and said dielectric material; and forming a primary layer upon said substantially planar surface substantially composed of material selected from the group consisting of polysilicon and a nitride material; forming a secondary layer upon said primary layer, said secondary layer being selected from the group consisting of polysilicon and a nitride material.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2002-11-22 | 2003-05-24 | 2003-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-22 | 2007-05-24 | 2007-11-23 | $3760.00 | Window Closed / Lapsed |
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