EP 1342128 A2 20030910 - PROJECTION SYSTEM FOR EUV LITHOGRAPHY
Title (en)
PROJECTION SYSTEM FOR EUV LITHOGRAPHY
Title (de)
PROJEKTIONSSYSTEM FÜR DIE EUV-LITHOGRAPHIE
Title (fr)
SYSTEME DE PROJECTION POUR LITHOGRAPHIE EUV
Publication
Application
Priority
- EP 0114301 W 20011206
- US 25516100 P 20001212
Abstract (en)
[origin: WO0248796A2] An EUV optical projection system includes at least six reflecting surfaces for imaging an object (OB) on an image (IM). The system is preferably configured to form an intermediate image (IMI) along an optical path from the object (OB) to the image (IM) between a secondary mirror (M2) and a tertiary mirror (M3), such that a primary mirror (M1) and the secondary mirror (M2) form a first optical group (G1) and the tertiary mirror (M3), a fourth mirror (M4), a fifth mirror (M5) and a sixth mirror (M6) form a second optical group (G2). The system also preferably includes an aperture stop (APE) located along the optical path from the object (OB) to the image (IM) between the primary mirror (M1) and the secondary mirror (M2). The secondary mirror (M2) is preferably concave, and the tertiary mirror (M3) is preferably convex. Each of the six reflecting surfaces preferably receives a chief ray (CR) from a central field-point at an incidence angle of less than substantially 15 DEG . The system preferably has a numerical aperture greater than 0.18 at the image (IM). The system is preferably configured such that a chief ray (CR) converges toward the optical axis (OA) while propagating between the secondary mirror (M2) and the tertiary mirror (M3).
IPC 1-7
IPC 8 full level
G21K 1/06 (2006.01); G02B 17/00 (2006.01); G02B 17/06 (2006.01); G03F 7/20 (2006.01); G21K 5/02 (2006.01); H01L 21/027 (2006.01)
CPC (source: EP KR)
G02B 17/0657 (2013.01 - EP); G03F 7/20 (2013.01 - KR); G03F 7/70233 (2013.01 - EP); G03F 7/70275 (2013.01 - EP)
Citation (search report)
See references of WO 0248796A2
Designated contracting state (EPC)
DE FR NL
DOCDB simple family (publication)
WO 0248796 A2 20020620; WO 0248796 A3 20030123; EP 1342128 A2 20030910; JP 2004516500 A 20040603; KR 20040024536 A 20040320
DOCDB simple family (application)
EP 0114301 W 20011206; EP 01270809 A 20011206; JP 2002550445 A 20011206; KR 20037007857 A 20030612