Title: A signal processing method, a method of adjusting a position detecting optical system, a target pattern, an exposure process, and an exposure apparatus
Application Number: 95116667 Application Date: 1995.08.24
Publication Number: 1123466 Publication Date: 1996.05.29
Approval Pub. Date: Granted Pub. Date:
International Classifi-cation: G03F7/20;H01L21/30;H01L21/77
Applicant(s) Name: Hitachi, Ltd. Address:
Inventor(s) Name: Tanisu Omori;Takahiro Machida;Nobuharu Kunikichi
Attorney & Agent: WANG YIPING
Abstract:
    The invention provides a target pattern which can obtain a position detection signal of excellent contrast and symmetry. A target pattern 1 detected by a position detecting optical system of the wavelength lambda , numerical aperture NA and partial coherence cr of an inspection light is formed of a repeating stepwise difference 1b of a dot or a line 1a of a protruding width W1 which is less than 0.5 lambda (l sigma)NA), a pitch P which is less than lambda (1 sigma /NA) disposed at the periphery, and a protruding width W2 which is less than 0.5 lambda (1 sigma )/NA). A target pattern 2 is formed of a repeating stepwise difference 2b of a dot or line 2a of a recess width W1 which is less than 0.5 lambda (1 sigma )/NA), a pitch P which is less than lambda (1 sigma )/NA), and a protruding width W2 which is less than 0.5 lambda (1 sigma )/NA).
Time: 9