公开(公告)号：JPH11354432A

公开(公告)日：1999-12-24

申请号：JP28281198

申请日：1998-10-05

Applicant: KOREA ELECTRONICS TELECOMM

Inventor： KIM DO FUN ,  YI KAKU HYUN ,  CHOI SAN SU ,  JEN HE BIN ,  KIM BO U

IPC: H01L21/027 ,  G02B5/30 ,  G03F7/20

Abstract: PROBLEM TO BE SOLVED: To augment the focal depth of an aligner, using a general process and photosensitive agent, by providing in its optical system a birefringent optical unit including translucent birefringent parts made of a birefringent substance, and by transcribing the images of a photomask in different positions from each other present along the optical axis of its optical system which are imaged respectively by the different polarization components from each other of its irradiation ray transmitted through its optical system. SOLUTION: In an optical system there is provided a birefringent optical unit 200 comprising translucent birefringent optical parts 210 made of a birefringent substance. The birefringent substance of which the birefringent optical parts 210 are made has different refractive indexes from each other respectively for rays 212, 213 having respective parallel and orthogonal linear polarizations to the optical axes of the birefringent substance. Correspondingly to this, the positions of image points 212a, 213a imaged respectively by the rays 212, 213 having the respective parallel and orthogonal linear polarizations to the optical axis of the birefringent substance are made of different from each other, leaving a predetermined space between them along the optical axis of the optical system. In this way, the focal depth of an aligner is augmented.