Ushio Denki Kabushiki Kaisha

Manabu Goto

Yoneta Tanaka

Masashi Shinbori

A polarized light irradiation apparatus, having at least two plane mirrors, is constructed to prevent reduction of the extinction ratio of the polarized light that irradiates a substrate when there is a change of the direction of polarization of the polarized light that is incident on a reflecting mirror. This is accomplished by forming a protection layer on the surface of the second plane mirror, and selecting the material and optical thickness of the layer in accordance with the angle of incidence and wavelength of the polarized light so that the difference &Dgr; of the phase shifts of the polarization P component and the polarization S component emerging from the second plane mirror satisfies the condition that &Dgr;&lE;&plusmn;20&deg;. By doing this, there will be no reduction of the extinction ratio of the polarized light that irradiates the substrate W if there is a change in the polarization direction of the polarized light that is incident on the second plane mirror.

Polarized light irradiation apparatus

A process for positioning, in which a dummy is not used, in which multichromatic light can be used as the light source for purposes of alignment, and in which aberration correction is unnecessary, and a device for executing the process is achieved according to the invention by executing projection onto a first mask by projection lenses in which at least the workpiece facing sides of the lenses are telocentric. In a state in which a workpiece is remote, light with exposure wavelengths is emitted from a light irradiation part onto a second mask. The first mask (or second mask) is moved such that the projected images of the alignment marks of the second mask and the alignment marks of the first mask come to lie on top of one another. Furthermore, the irradiation light is branched off by beam splitters and positions of the alignment marks of the second mask are stored. Next, emission of the light with exposure wavelengths is stopped, a workpiece is inserted into a predetermined position, from another light irradiation part light multichrome with nonexposure wavelengths is emitted, positions of the alignment marks of the workpiece are determined and the workpiece is moved to bring these alignment marks into position on top of the stored position of the alignment marks of the second mask.

Process for positioning of a mask relative to another mask, or masks

An exposure device in which alignment is performed using light with wavelengths which are different from those of the exposure light, to position the mask to the workpiece with high accuracy by the magnification factor in emission of exposure light being brought into agreement with the magnification factor for emission of nonexposure light. Changes in the focal length and movements of the main planes of the projection lens due to the different wavelengths are taken into consideration in adjusting the distance between the mask and the projection lens and the distance between the projection lens and the workpiece. In this way, the length of the optical path of the optical system is adjusted such that the magnification factor in the emission of nonexposure light matches the magnification factor in emission of exposure light. Then, the nonexposure light is emitted onto a mask, and the workpiece drive carrier or the mask drive carrier is moved such that the alignment identifier of the workpiece with the alignment identifier of the mask come to lie one on top of the other. Furthermore, instead of adjusting the distance between the mask and the projection lens and the distance between the projection lens and the workpiece, an optical part such as a parallel flat plate or the like is inserted into the optical path for adjusting its length.

Process for positioning a mask relative to a workpiece and device

In a film exposure apparatus and method of exposure using the same which are disclosed herein, a plurality of frames arranged in a longitudinal direction of a belt-shaped film are exposed sequentially to light for transcript of an image onto each of the frames. The film exposure apparatus comprises an illumination system, a photomask disposed at a location to which light from the illumination system is applied, a photomask position adjusting mechanism, a projection lens of projecting an image of the photomask irradiated, and a film feed mechanism for step-feeding the film one frame by one frame. The belt-shaped film is provided with at least two or more film-side alignment marks on each frame, and the photomask is provided with a circuit pattern whose image is to be projected and transferred onto the film, and photomask-side alignment marks in correspondence to the film-side alignment marks.

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Yokohama, Japan

Manabu Goto