Title:
METHOD AND DEVICE FOR ALIGNMENT
Document Type and Number:
Japanese Patent JPS63208703
Kind Code:
A
Abstract:
PURPOSE:To detect the position of a step pattern with high accuracy by making the reflected light of 1st light from the step pattern and reference light obtained from the reflecting surface of 2nd light interface with each other and thus forming interference fringes. CONSTITUTION:A semiconductor wafer 1 is moved and light is projected from a reducing lens 8 on the step pattern 1a of a target. Homogeneous light 4 is passed through an optical fiber 9 and split by a beam splitter 10 into two light beams. One light beam passes through a relay lens 11, a mirror 12, and the reducing lens 8 and is reflected by the step pattern 1a to travels back in the opposite direction, thereby entering a television camera 13. The other light beam passes through a reference lens 14, a mirror 15, and a flare lens 16 and is reflected by a reference mirror 3 slanted by a fine angle DELTAtheta to enter the television camera 13, thereby forming light interference fringes.
Inventors:
KOMORIYA SUSUMU
MAEJIMA HIROSHI
IRIKITA NOBUYUKI
NAKAGAWA SHINYA
MAEJIMA HIROSHI
IRIKITA NOBUYUKI
NAKAGAWA SHINYA
Application Number:
JP4027787A
Publication Date:
August 30, 1988
Filing Date:
February 25, 1987
Export Citation:
Assignee:
HITACHI LTD
International Classes:
G03F9/00; G01B11/00; H01L21/027; H01L21/30; H01L21/68; (IPC1-7): G01B11/00; G03F9/00; H01L21/30; H01L21/68
Attorney, Agent or Firm:
Katsuo Ogawa
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