US5986824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Large NA projection lens system with aplanatic lens element for excimer laser lithography
Assignee: Nikon Corp
•
Filing: 1998-06-04
•
Granted: 1999-11-16
•
Expires: 2018-06-04
Abstract
Abstract Projection lens systems for transferring a pattern on a reticle onto a wafer having an aplanatic lens element. The aplanatic lens element has a shape factor between 0.1 and 0.224, the projection lens system satisfies the condition: -2.0<f ap /F<-0.6251, where f ap is the focal length of the aplanatic lens element and F is the focal length of the projection optical lens system. The projection optical lens system further satisfies the condition 2.6<|f G3 /f G |<4.64.
Inventors
- 👤 Romeo I. Mercado
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:45
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70216; G03F7/70241; G02; G02B; G02B13/00; G02B13/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
90 words
A projection exposure apparatus for transferring a pattern on a reticle onto a wafer, the apparatus comprising a projection optical lens system comprising in order from an object side to an image side: a first group of lens elements having a positive refractive power; a second group of lens elements having a negative refractive power; a third group of lens elements having a positive refractive power; and a fourth group of lens elements having a positive refractive power, the fourth group of lens elements including a substantially aplanatic lens element.
Claim 2
Dependent Claim
90 words
A projection exposure apparatus for transferring a pattern on a reticle onto a wafer, the apparatus comprising a projection optical lens system comprising in order from an object side to an image side: a first group of lens elements having a positive refractive power; a second group of lens elements having a negative refractive power; a third group of lens elements having a positive refractive power; and a fourth group of lens elements having a positive refractive power, the fourth group of lens elements including a substantially aplanatic lens element.
Claim 3
Dependent Claim
74 words
The projection exposure apparatus of claim 1 wherein the substantially aplanatic lens element satisfies the following condition: 0.1<(R.sub.1 -R.sub.2)/(R.sub.1 +R.sub.2)<0.224, where R 1 is the radius of curvature of a surface of the substantially aplanatic lens element facing an object side of the projection optical lens system and R 2 is the radius of curvature of a surface of the substantially aplanatic lens element facing an image side of the projection optical lens system.
Claim 4
Dependent Claim
43 words
The projection exposure apparatus of claim 2 wherein the projection optical lens system satisfies the following condition: -2.0<f.sub.ap /F<-0.6251, where f ap is a focal length of the aplanatic lens element and F is the focal length of the projection optical lens system.
Claim 5
Dependent Claim
48 words
The projection exposure apparatus of claim 1 wherein the projection optical lens system satisfies the following condition: 2.6<|f.sub.G3 /f.sub.G2 |<4.64, where f G2 is the focal length of the second group of lens elements and f G3 is the focal length of the third group of lens elements.
Claim 6
Dependent Claim
29 words
The projection exposure apparatus of claim 4 wherein the fourth group of lens elements includes at least one meniscus lens element having a concave surface facing the image side.
Claim 7
Dependent Claim
30 words
The projection exposure apparatus of claim 5 wherein the fourth group of lens elements includes more than one meniscus lens element each having a concave surface facing the image side.
Claim 8
Dependent Claim
23 words
The projection exposure apparatus of claim 6 wherein the substantially aplanatic lens element is a meniscus lens element having a negative refractive power.
Claim 9
Dependent Claim
49 words
The projection exposure apparatus of claim 7 wherein the fourth group of lens elements include a triplet sub-group of lens elements made up of a lens element having a positive refractive power, a lens element having a negative refractive power, and a lens element having a positive refractive power.
Claim 10
Dependent Claim
43 words
The projection exposure apparatus of claim 1 wherein the projection optical lens system satisfies the following condition: -2.0<f.sub.ap /F<-0.6251, where f ap is a focal length of the substantially aplanatic lens element and F is focal length of the projection optical lens system.
References Cited (Backward Citations)
US4891663A
Cited
US4812028A
Cited
US4770477A
Cited
US4964704A
Cited
US4948238A
Cited
US5142409A
Cited
US5260832A
Cited
US5448408A
Cited
US5323263A
Cited
US5555479A
Cited
US5519537A
Cited
US5636000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-15 | 2003-05-17 | 2003-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-15 | 2007-05-17 | 2007-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-15 | 2011-05-17 | 2011-11-16 | $7700.00 | Window Closed / Lapsed |