Nikon Corporation

Hideki Koitabashi

Masamitsu Yanagihara

Seiji Miyazaki

Kei Nara

Junji Hazama

Hiroshi Kitano

Yoshiyuki Katamata

Kei Hara

Yoichi Hamashima

In order to provide a search alignment method capable of high-speed alignment without a relative movement between an alignment system and a substrate, an alignment mark is constituted by a plurality of element marks having shapes different from each other, the plurality of element marks are provided in such a manner that each two of them has a gap a little shorter than the size of the field of view of the alignment system therebetween, and if even one of the element marks constituting the alignment mark comes into the field of view of the alignment system, said element mark is identified out of all of said element marks, whereby the position of the entire alignment is measured from the position of said one element mark. Therefore, if the alignment mark is moved in a range wider than the field of view of the alignment system, it is possible to detect the position of the alignment mark by one measurement.

Alignment method, exposure method, and exposure apparatus

Positional discrepancies of images of segmental areas, which are caused by stretching of a substrate in the Y direction, are corrected by changing magnifications of respective projection optical systems and inclinations of parallel plane glass pieces with respect optical axes. After that, positional discrepancies of the images after the correction are accurately detected by using a calibration system for the projection optical systems. Thus it is possible to confirm whether or not the positional discrepancies are accurately corrected. If the correction is insufficient as a result of the confirmation, at least one of correction of the magnifications of the respective projection optical systems and shift of the images projected through the respective projection optical systems onto the substrate is executed again so that amounts of the positional discrepancies are sufficiently small. On the other hand, the positional discrepancy can be easily determined by storing positional information and a detected signal concerning an image formed by a projection optical system in synchronization with a clock, followed by signal processing.

Projection exposure apparatus, method for correcting positional

Alignment method utilizing plurality of marks, discriminable from each

An image in which a feature corresponding to a reference mark formed at a predetermined position in an exposure apparatus is formed at a predetermined position in an arbitrary area is stored as a reference image, and a reference image including an image corresponding to the reference mark is detected from an image to be processed obtained by picking up an image near the reference mark to detect the position of the reference mark in the image to be processed, thus enabling detection of the positional relationship between a reference in the exposure apparatus and substrate alignment means.

Position detection method

A position detecting method detects each position of a photosensitive substrate when executing shots of circuit patterns so that the circuit patterns are further superposed on the photosensitive substrate already formed with the circuit patterns. The method comprises the steps of performing a shot of a circuit pattern of a reticle in superposition on liquid crystal pixel segments already formed on a glass plate, registering, in a memory, a circuit pattern as a reference image in the liquid crystal pixel segment and performing pattern matching with other fields of the liquid crystal pixel segments by use of this reference image. An alignment is conducted based on a position of circuit pattern extracted thereby.

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Tokyo, Japan

Hideki Koitabashi