Title:
【発明の名称】干渉光学系及びそれを備えた露光装置
Document Type and Number:
Japanese Patent JP2810194
Kind Code:
B2
Abstract:
PURPOSE:To enable high-accuracy interference measurement by interposing a solid material which is transparent to in-use wavelength in the reference optical path and measurement optical path of the interference optical system. CONSTITUTION:The parallel beam from a laser source 1 is split into two by a half- mirror 2, and the reference light 3 after being reflected by a reflecting mirror 6 is transmitted through a cube half-mirror 7 and a glass bar 10 and then made incident on a reference mirror 5. The measurement beam 4, on the other hand, is transmitted through the mirror 7 and glass bar 10, then reflected by the surface of a wafer 16, and made incident on the mirror 5. The beams 3 and 4 which are reflected by the mirror 5 are reflected by the mirror 7, then transmitted through a lens 8 and a glass bar 11, and put one over the other on a linear sensor 9 to form interference fringes. For the purpose, the pitch and phase variation of the interference fringes are detected to know the inclination and height of the wafer 16. Namely, when the wafer 16 moves up and down, the interference fringes shift in phase and when the wafer 16 slants, the pitch of the interference fringes varies. Then the temperature, pressure, and humidity variation of air does not operate directly on the interference optical path by the insertion of the glass bars 10 and 11 of athermal glass, etc., to remove the influence of fluctuations of the air.
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Inventors:
Minoru Tanaka
Yoshitada Oshida
Tetsuzo Tanimoto
Yoshitada Oshida
Tetsuzo Tanimoto
Application Number:
JP5359690A
Publication Date:
October 15, 1998
Filing Date:
March 07, 1990
Export Citation:
Assignee:
株式会社日立製作所
International Classes:
G01B9/02; G01B11/00; G01B11/24; G03F7/20; H01L21/027; H01L21/30; (IPC1-7): G01B9/02; G01B11/00; H01L21/027
Domestic Patent References:
| JP57173704A | ||||
| JP6281505A |
Attorney, Agent or Firm:
Katsuo Ogawa (1 person outside)