SU1659955A1 - 1,5 magnification projection objective - Google Patents

Abstract

FIELD: optical instrumentation; used in microelectronics. The purpose of the invention is to increase the numerical aperture and the field of view in the course of telecentric rays in the space of objects. The lens contains positive menisci 1, 3, 9, 10, 13, 18, negative menisci 4, 6, 11, 12, two-convex lenses 2, 7, 8, 14-16. Chislov aperture 0.35; field of view 21.2 mm. 2 Il.

Description

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FIG. one

The invention relates to optical systems and can be used in microelectronics in projection exposure systems for the manufacture of semiconductor devices.

The purpose of the invention is to increase the numerical aperture and the field of view in the course of telecentric rays in the space of objects.

Figure 1 shows the optical layout of the proposed lens; figure 2 - MTF lens.

The lens consists of eighteen lenses, assembled into fourteen components, and an aperture diaphragm.

The first component consists of a positive meniscus 1 and a double-convex lens 2 and a positive meniscus 3.

The positive meniscus 1, facing concavity to the plane of objects, is made of crown and has a ratio of radii of 3.17: 1. The double-convex lens 2 is made of a crown with a ratio of 1: 2.59 radius. The positive meniscus 3, convex to the plane of objects, is made of crown and has a ratio of radii of 1: 5.24.

The second component, the negative meniscus 4, which is convex to the plane of objects, is made of a light flint, with a radius ratio of 19.36: 1.

The third component is a double-bent lens 5, made of light flint with a ratio of radii of 1: 2.23.

The fourth component, the negative meniscus 6, facing inward to the plane of the object, is made of a crown with a ratio of 1: 1.26 radii.

The fifth component is a double-convex lens 7, made of a special crown with a radius ratio of 12.02: 1, located behind the fourth component at a distance from it equal to 0.035 of the objective focal length.

The sixth component is a twin-domed lens 8, made of a special crown with a ratio of 1: 1.30 radii.

The seventh component - the positive meniscus 9, which is convex to the plane of objects, is made of a special crown with a ratio of radii of 1: 6.71.

The eighth component, the positive meniscus 10, which is convex to the plane of objects, is made of a heavy crown with a ratio of 1: 1.6 radii.

The ninth component, the negative meniscus 11, which is convex to the plane of objects, is made of light flint with a radius ratio of 12.18: 1.

The tenth component is a negative meniscus, facing by concavity to the plane of objects and glued together from negative 12 and positive 13 menisci,

made of light flint and crown, respectively, the refractive index difference of the lenses included in the component is 0.07. The difference in dispersion is 22.65, and the ratio of external radii is 1: 1.4t.

0 The eleventh component is a binary. The lens lens 14, made of a special crown with a ratio of 4.72: 1 radii.

The twelfth component is a twin lens coaxial lens 15, made of a special

5 krone with a ratio of 1: 2.64 radii.

The thirteenth component is a positive meniscus convex to the plane of objects and glued together from a double convex 16 and double convex 17 lenses,

0 made of light crown and light

flint; refractive index difference

lenses is 0.12, the difference in dispersions

- 25.5, and the ratio of the outer radii

1.24: 1; located beyond the twelfth component at a distance of 0.032 from the lens focal length.

The fourteenth component - a positive meniscus 18, convex to the plane of objects, is made of

0 light flint with a radius ratio of 1: 3.46.

The lens has a high degree of aberration correction for a spectral range of 365.0 ± 4 mm. Lens magnification -

5 Aperture 0.35, field of view 21.2 mm.

The longitudinal spherical aberration is no more than 0.00727, the astigmatic difference is no more than 0.003 mm, the dispersion is no more than 0.0004%, the increase chromatism is no more

0 0.00037 mm, aberrations of wide meridional beams no more than 0.00252 mm.

According to the proposed concept, an objective with a spectral range of 404.66 ± 5 mm was also calculated.

five

Claims (1)

Claims of the invention. A projection lens with a magnification of 1 / 5x containing eleven components and an aperture diaphragm, the first component being a negative meniscus convex to the object, the second is a negative meniscus, the third is a two-fold lens, a fourth positive lens, and the fifth is positive5 the first meniscus convex to the object, the sixth is the meniscus convex to the object, the seventh is the negative meniscus convex to the object, the eighth is the negative meniscus facing by concavity to subject. the ninth is a positive lens, the tenth is a double-convex lens, the eleventh is a positive meniscus convex to the object and glued together from a positive and negative lenses, in order to increase the numerical aperture and visual field during the telecentric course rays in the space of objects, in front of the first component there is a positive component of two positive meniscuses convex to each other, and a two-convex lens between them, between the first and second components the lens is encapsulated, the second component faces the object in concavity, the fourth is made as a two-convex lens, the sixth is made positive, the eighth is made of glued negative and positive menisci, the ninth is made 5 as a two-convex lens, the eleventh component has a positive meniscus, convex to the object, with the aperture diaphragm placed behind the seventh component on 10 away from it, equal to 0.01 of the focal length of the lens, the distance between the second and third components is 0.035 of the focal length of the lens, and the distance between the tenth and eleventh The 15 components make up the 0.032 focal length of the lens. 750 e 1000 FIG. 2 1, / uh / mm