US5750442A
Expired / Lapsed
US
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Germanium as an antireflective coating and method of use
Assignee: Micron Technology Inc
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Filing: 1995-09-25
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Granted: 1998-05-12
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Expires: 2015-09-25
Abstract
Abstract Germanium is employed as an antireflective coating material for use in active area lithography and gate area lithography steps in the formation of a semiconductor integrated circuit. A germanium layer is deposited over an active area nitride layer or over a gate area nitride layer, and a photoresist layer is then formed on the germanium layer. The photoresist layer is than exposed and developed. During exposure, the germanium layer substantially reduces reflection from the underlying nitride layer, thereby relieving the dependency of exposure energy and resulting line width on the underlying nitride layer thickness. Germanium-silicon may also be employed as the antireflective layer.
Inventors
- 👤 Werner Juengling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:22
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/30; G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01326; H10P; H10P14/00; H10P14/60; H10P14/61; H10P50/00; H10P50/73; H10P76/00; H10P76/20; H10P76/204; H10P76/2041; H10P76/2043; H10W10/01; H10W10/011; H10W10/012; H10W10/031; H10W10/10; H10W10/13; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/947; Y10S438/948; Y10S438/95; Y10S438/952
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
100 words
A method for improved line width control during photolithography patterning of stack layers on a semiconductor wafer, the process comprising the steps of: (a) depositing a plurality of stack layers upon a silicon substrate; (b) depositing over said plurality of active area stack layers an antireflective layer of a material substantially composed of germanium; (c) forming a layer of photoresist upon said antireflective layer; (d) exposing said layer of photoresist; (e) developing said layer of photoresist; (f) etching said plurality of stack layers; (g) ashing said layer of photoresist, leaving a residue of photoresist; and (h) removing said antireflective layer.
Claim 2
Independent Claim
100 words
A method for improved line width control during photolithography patterning of stack layers on a semiconductor wafer, the process comprising the steps of: (a) depositing a plurality of stack layers upon a silicon substrate; (b) depositing over said plurality of active area stack layers an antireflective layer of a material substantially composed of germanium; (c) forming a layer of photoresist upon said antireflective layer; (d) exposing said layer of photoresist; (e) developing said layer of photoresist; (f) etching said plurality of stack layers; (g) ashing said layer of photoresist, leaving a residue of photoresist; and (h) removing said antireflective layer.
Claim 3
Dependent Claim
18 words
The method as defined in claim 1 where the layer of germanium is deposited upon a passivation layer.
Claim 4
Dependent Claim
19 words
The method of claim 2, wherein the passivation layer of the stack layers is an uppermost silicon nitride layer.
Claim 5
Dependent Claim
21 words
The method as defined in claim 1, wherein said passivation layer has a thickness in the range of about 1200-2400 Angstroms.
Claim 6
Dependent Claim
23 words
The method as defined in claim 1, further comprising the step of patterning said plurality of stack layers as active area stack layers.
Claim 7
Dependent Claim
22 words
The method as defined in claim 1, further comprising the step of patterning said plurality of stack layers as gate stack layers.
Claim 8
Dependent Claim
41 words
The method as defined in claim 1, wherein said antireflective layer is substantially composed of Si x Ge y , and wherein the value of x is about 0 to 0.2 and the value of y is about 1.0 to 0.8.
Claim 9
Dependent Claim
19 words
The method as defined in claim 1, wherein the step of removing said antireflective layer comprises a piranha clean.
Claim 10
Dependent Claim
24 words
The method as defined in claim 1, wherein said anti-reflective layer has a thickness in a range of about 200 Angstroms to 800 Angstroms.
Claim 11
Dependent Claim
25 words
The method as defined in claim 1 wherein the step of removing said antireflective layer results in the complete removal of said residue of photoresist.
Claim 12
Independent Claim
112 words
A method for improved line width control during photolithography patterning of stack layers on a semiconductor wafer, the process comprising the steps of: (a) depositing a plurality of stack layers upon a silicon substrate, the uppermost layer of said plurality of stack layers being a silicon nitride layer; (b) depositing over said silicon nitride layer an antireflective layer of a material substantially composed of germanium; (c) forming a layer of photoresist upon said antireflective layer; (d) exposing said layer of photoresist; (e) developing said layer of photoresist; (f) etching said plurality of stack layers; (g) ashing said layer of photoresist, resulting in a residue of photoresist; and (h) removing said antireflective layer.
Claim 13
Independent Claim
112 words
A method for improved line width control during photolithography patterning of stack layers on a semiconductor wafer, the process comprising the steps of: (a) depositing a plurality of stack layers upon a silicon substrate, the uppermost layer of said plurality of stack layers being a silicon nitride layer; (b) depositing over said silicon nitride layer an antireflective layer of a material substantially composed of germanium; (c) forming a layer of photoresist upon said antireflective layer; (d) exposing said layer of photoresist; (e) developing said layer of photoresist; (f) etching said plurality of stack layers; (g) ashing said layer of photoresist, resulting in a residue of photoresist; and (h) removing said antireflective layer.
Claim 14
Dependent Claim
22 words
The method as defined in claim 11, wherein the silicon nitride layer has a thickness in the range of about 1200-2400 Angstroms.
Claim 15
Dependent Claim
23 words
The method as defined in claim 11, further comprising the step of patterning said plurality of stack layers as active area stack layers.
Claim 16
Dependent Claim
22 words
The method as defined in claim 11, further comprising the step of patterning said plurality of stack layers as gate stack layers.
Claim 17
Dependent Claim
41 words
The method as defined in claim 11, wherein said antireflective layer is substantially composed of Si x Ge y , and wherein the value of x is about 0 to 0.2 and the value of y is about 1.0 to 0.8.
Claim 18
Dependent Claim
19 words
The method as defined in claim 11, wherein the step of removing said antireflective layer comprises a piranha clean.
Claim 19
Dependent Claim
24 words
The method as defined in claim 11, wherein said anti-reflective layer has a thickness in a range of about 200 Angstroms to 800 Angstroms.
Claim 20
Dependent Claim
25 words
The method as defined in claim 11 wherein the step of removing said antireflective layer results in the complete removal of said residue of photoresist.
Claim 21
Dependent Claim
25 words
The method as defined in claim 11 wherein the step of removing said antireflective layer results in the complete removal of said residue of photoresist.
Claim 22
Independent Claim
127 words
A method for photolithography patterning comprising: depositing a plurality of stack layers upon a silicon substrate, the uppermost layer of said plurality of stack layers being a silicon nitride layer having a thickness in the range of about 1200-2400 Angstroms; depositing over said silicon nitride layer an antireflective layer of a material substantially composed of Si x Ge y having a thickness in a range of about 200 Angstroms to 800 Angstroms, and wherein the value of x is about 0 to 0.2 and the value of y is about 1.0 to 0.8, forming a layer of photoresist upon said antireflective layer; exposing said layer of photoresist; developing said layer of photoresist; etching said plurality of stack layers; ashing said layer of photoresist; removing said antireflective layer.
Claim 23
Independent Claim
127 words
A method for photolithography patterning comprising: depositing a plurality of stack layers upon a silicon substrate, the uppermost layer of said plurality of stack layers being a silicon nitride layer having a thickness in the range of about 1200-2400 Angstroms; depositing over said silicon nitride layer an antireflective layer of a material substantially composed of Si x Ge y having a thickness in a range of about 200 Angstroms to 800 Angstroms, and wherein the value of x is about 0 to 0.2 and the value of y is about 1.0 to 0.8, forming a layer of photoresist upon said antireflective layer; exposing said layer of photoresist; developing said layer of photoresist; etching said plurality of stack layers; ashing said layer of photoresist; removing said antireflective layer.
Claim 24
Dependent Claim
20 words
The method as defined in claim 20, further comprising patterning said plurality of stack layers as active area stack layers.
Claim 25
Dependent Claim
20 words
The method as defined in claim 20, further comprising patterning said plurality of stack layers as gate area stack layers.
Claim 26
Independent Claim
30 words
A method for forming a structure comprising: providing a dielectric layer; forming an antireflective layer comprising germanium upon said dielectric layer; selectively removing said dielectric layer beneath said antireflective layer.
Claim 27
Independent Claim
30 words
A method for forming a structure comprising: providing a dielectric layer; forming an antireflective layer comprising germanium upon said dielectric layer; selectively removing said dielectric layer beneath said antireflective layer.
Claim 28
Dependent Claim
13 words
The method as defined in claim 23, further comprising removing said antireflective layer.
Claim 29
Dependent Claim
53 words
The method as defined in claim 23, wherein selectively removing said dielectric layer beneath said antireflective layer comprises: forming a layer of photoresist upon said antireflective layer; exposing said layer of photoresist; developing said layer of photoresist to form a pattern therein; removing said dielectric layer and said antireflective layer through the pattern.
Claim 30
Dependent Claim
19 words
The method as defined in claim 25, further comprising: removing said layer of photoresist; and removing said antireflective layer.
Claim 31
Dependent Claim
15 words
The method of claim 23, wherein the dielectric layer is substantially composed of silicon nitride.
Claim 32
Dependent Claim
19 words
The method of claim 23, wherein the dielectric layer has a thickness in the range of about 200-2400 Angstroms.
Claim 33
Dependent Claim
20 words
The method as defined in claim 23, wherein said antireflective layer is substantially composed of Si x Ge y .
Claim 34
Dependent Claim
27 words
The method as defined in claim 29, wherein the value of x is about 0 to 0.2 and the value of y is about 1.0 to 0.8.
Claim 35
Dependent Claim
48 words
The method as defined in claim 27, wherein dielectric layer is upon an a refractory metal silicide layer which is upon an electrically conductive layer, wherein selectively removing said dielectric layer beneath said antireflective layer also selectively removes said refractory metal silicide layer and said electrically conductive layer.
Claim 36
Dependent Claim
29 words
The method as defined in claim 23, wherein selectively removing said dielectric layer beneath said antireflective layer comprises an anisotropic etch of said dielectric layer and said antireflective layer.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 2001-05-11 | 2001-11-10 | 2002-05-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-11 | 2005-11-10 | 2006-05-12 | $3760.00 | Window Closed / Lapsed |
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