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US5330883A
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Techniques for uniformizing photoresist thickness and critical dimension of underlying features
Assignee: LSI Corp
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Filing: 1992-06-29
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Granted: 1994-07-19
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Expires: 2012-06-29
Abstract
Abstract Changing (varying, irregular) resist thickness on semiconductor wafers having irregular top surface topography or having different island sizes, affects the percent reflectance (and absorption efficiency) of incident photolithographic light, and consequently the critical dimensions of underlying features being formed (e.g., polysilicon gates). A low solvent content resist solution that can be applied as an aerosol provides a more uniform thickness resist film, eliminating or diminishing photoresist thickness variations. A top antireflective coating (TAR) also aids in uniformizing reflectance, despite resist thickness variations. The two techniques can be used alone, or together. Hence, better control over underlying gate size can be effected, without differential biasing.
Inventors
- 👤 Mario Garza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:19
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/20; G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/091; G03F7/16; Y; Y10; Y10S; Y10S430/00; Y10S430/151
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
193 words
Method of fabricating semiconductor features having uniform critical dimensions (cd's), comprising: applying a film of photoresist over a semiconductor wafer, for defining underlying features having critical cd's; applying a top antireflective coating of a partially-fluorinated compound selected from the group consisting of: (a) R f CH 2 CH 2 SCH 2 CH 2 CO 2 Li; (b) (R f CH 2 CH 2 O)P(O)(ONH 4 ) 2 ; (c) (R f CH 2 CH 2 O) 2 P(O)(ONH 4 ); (d) (R f CH 2 CH 2 O)P(O)(OH) 2 ; (e) (R f CH 2 CH 2 O) 2 P(O)(OH); (f) R f CH 2 CH 2 SCH 2 CH 2 N + (CH 3 ) 3 CH 3 SO 4 - ; (g) R f CH 2 CH(OCOCH 3 )CH 2 N + (CH 3 ) 2 CH 2 CO 2 - ; (h) R f CH 2 CH 2 SO 3 X (X=H and NH 4 ); wherein: R f =F(CF 2 CF 2 ) 3-8 over the film of photoresist; and exposing the photoresist to masked light to form a pattern in the photoresist, said pattern defining the underlying features.
Claim 2
Dependent Claim
193 words
Method of fabricating semiconductor features having uniform critical dimensions (cd's), comprising: applying a film of photoresist over a semiconductor wafer, for defining underlying features having critical cd's; applying a top antireflective coating of a partially-fluorinated compound selected from the group consisting of: (a) R f CH 2 CH 2 SCH 2 CH 2 CO 2 Li; (b) (R f CH 2 CH 2 O)P(O)(ONH 4 ) 2 ; (c) (R f CH 2 CH 2 O) 2 P(O)(ONH 4 ); (d) (R f CH 2 CH 2 O)P(O)(OH) 2 ; (e) (R f CH 2 CH 2 O) 2 P(O)(OH); (f) R f CH 2 CH 2 SCH 2 CH 2 N + (CH 3 ) 3 CH 3 SO 4 - ; (g) R f CH 2 CH(OCOCH 3 )CH 2 N + (CH 3 ) 2 CH 2 CO 2 - ; (h) R f CH 2 CH 2 SO 3 X (X=H and NH 4 ); wherein: R f =F(CF 2 CF 2 ) 3-8 over the film of photoresist; and exposing the photoresist to masked light to form a pattern in the photoresist, said pattern defining the underlying features.
Claim 3
Dependent Claim
167 words
Method of uniformizing the reflectivity of photoresist having varying thickness, comprising: applying a film of photoresist over a semiconductor wafer; and applying a top antireflective coating of a partially-fluorinated compound selected from the group consisting of: (a) R f CH 2 CH 2 SCH 2 CH 2 CO 2 Li; (b) (R f CH 2 CH 2 O)P(O)(ONH 4 ) 2 ; (c) (R f CH 2 CH 2 O) 2 P(O)(ONH 4 ); (d) (R f CH 2 CH 2 O)P(O)(OH) 2 ; (e) (R f CH 2 CH 2 O) 2 P(O)(OH); (f) R f CH 2 CH 2 SCH 2 CH 2 N + (CH 3 ) 3 CH 3 SO 4 - ; (g) R f CH 2 CH(OCOCH 3 )CH 2 N + (CH 3 ) 2 CH 2 CO 2 - ; (h) R f CH 2 CH 2 SO 3 X (X=H and NH 4 ); wherein: R f =F(CF 2 CF 2 ) 3-8 over the film of photoresist.
Claim 4
Dependent Claim
167 words
Method of uniformizing the reflectivity of photoresist having varying thickness, comprising: applying a film of photoresist over a semiconductor wafer; and applying a top antireflective coating of a partially-fluorinated compound selected from the group consisting of: (a) R f CH 2 CH 2 SCH 2 CH 2 CO 2 Li; (b) (R f CH 2 CH 2 O)P(O)(ONH 4 ) 2 ; (c) (R f CH 2 CH 2 O) 2 P(O)(ONH 4 ); (d) (R f CH 2 CH 2 O)P(O)(OH) 2 ; (e) (R f CH 2 CH 2 O) 2 P(O)(OH); (f) R f CH 2 CH 2 SCH 2 CH 2 N + (CH 3 ) 3 CH 3 SO 4 - ; (g) R f CH 2 CH(OCOCH 3 )CH 2 N + (CH 3 ) 2 CH 2 CO 2 - ; (h) R f CH 2 CH 2 SO 3 X (X=H and NH 4 ); wherein: R f =F(CF 2 CF 2 ) 3-8 over the film of photoresist.
Claim 5
Dependent Claim
191 words
Method of uniformizing the reflectivity of photoresist having varying thickness, comprising: creating a solution of approximately 5% (five percent) casting solvent, and 95% (ninety-five percent) solids; applying the solution as an aerosol to a semiconductor wafer, thereby forming a film of photoresist on a wafer; applying a top antireflective coating of a partially-fluorinated compound selected from the groups consisting of: (a) R f CH 2 CH 2 SCH 2 CH 2 CO 2 Li; (b) (R f CH 2 CH 2 O)P(O)(ONH 4 ) 2 ; (c) (R f CH 2 CH 2 O) 2 P(O)(ONH 4 ); (d) (R f CH 2 CH 2 O)P(O)(OH) 2 ; (e) (R f CH 2 CH 2 O) 2 P(O)(OH); (f) R f CH 2 CH 2 SCH 2 CH 2 N + (CH 3 ) 3 CH 3 SO 4 - ; (g) R f CH 2 CH(OCOCH 3 )CH 2 N + (CH 3 ) 2 CH 2 CO 2 - ; (h) R f CH 2 CH 2 SO 3 X (X=H and NH 4 ); wherein: R f =F(CF 2 CF 2 ) 3-8 over the film of photoresist.
Claim 6
Dependent Claim
191 words
Method of uniformizing the reflectivity of photoresist having varying thickness, comprising: creating a solution of approximately 5% (five percent) casting solvent, and 95% (ninety-five percent) solids; applying the solution as an aerosol to a semiconductor wafer, thereby forming a film of photoresist on a wafer; applying a top antireflective coating of a partially-fluorinated compound selected from the groups consisting of: (a) R f CH 2 CH 2 SCH 2 CH 2 CO 2 Li; (b) (R f CH 2 CH 2 O)P(O)(ONH 4 ) 2 ; (c) (R f CH 2 CH 2 O) 2 P(O)(ONH 4 ); (d) (R f CH 2 CH 2 O)P(O)(OH) 2 ; (e) (R f CH 2 CH 2 O) 2 P(O)(OH); (f) R f CH 2 CH 2 SCH 2 CH 2 N + (CH 3 ) 3 CH 3 SO 4 - ; (g) R f CH 2 CH(OCOCH 3 )CH 2 N + (CH 3 ) 2 CH 2 CO 2 - ; (h) R f CH 2 CH 2 SO 3 X (X=H and NH 4 ); wherein: R f =F(CF 2 CF 2 ) 3-8 over the film of photoresist.
References Cited (Backward Citations)
US4201586A
Cited
US4282118A
Cited
US4402128A
Cited
US4506434A
Cited
US4710254A
Cited
US4541169A
Cited
US4665007A
Cited
US4929992A
Cited
US4672023A
Cited
US4762396A
Cited
US5008156A
Cited
US4698128A
Cited
US4873176A
Cited
US4906852A
Cited
US5002851A
Cited
US5177172A
Cited
US5001040A
Cited
US5178986A
Cited
US5063138A
Cited
US4912022A
Cited
US4977330A
Cited
US5178989A
Cited
US4992260A
Cited
US5055871A
Cited
US5266455A
Cited
US5075257A
Cited
US5178955A
Cited
US5168001A
Cited
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