阅读说明：本技术 一种光刻投影物镜 (Photoetching projection objective lens ) 是由 安福平 储兆祥 于 2018-07-27 设计创作，主要内容包括：本发明实施例提供一种光刻投影物镜,所述光刻投影物镜包括沿光轴顺次排列的第一透镜组、第二透镜组、光阑、第三透镜组和第四透镜组,所述光阑所在平面为光阑面,所述第一透镜组与所述第四透镜组关于所述光阑面对称,所述第二透镜组与所述第三透镜组关于所述光阑面对称；所述第一透镜组和所述第四透镜组具有正的光焦度,所述第二透镜组和所述第三透镜组具有负的光焦度；所述第一透镜组以及所述第四透镜组均包括两个双凹负透镜、两个双凸正透镜和一个弯月正透镜,所述第二透镜组以及所述第三透镜组均包括两个弯月负透镜、一个双凹负透镜和一个双凸正透镜。本发明实施例提供一种光刻投影物镜,增大了投影曝光装置的视场尺寸,提升了产率。(The embodiment of the invention provides a photoetching projection objective which comprises a first lens group, a second lens group, a diaphragm, a third lens group and a fourth lens group which are sequentially arranged along an optical axis, wherein the plane where the diaphragm is located is a diaphragm surface, the first lens group and the fourth lens group are symmetrical relative to the diaphragm surface, and the second lens group and the third lens group are symmetrical relative to the diaphragm surface; the first lens group and the fourth lens group have positive optical power, and the second lens group and the third lens group have negative optical power; the first lens group and the fourth lens group each include two biconcave negative lenses, two biconvex positive lenses and one meniscus positive lens, and the second lens group and the third lens group each include two meniscus negative lenses, one biconcave negative lens and one biconvex positive lens. The embodiment of the invention provides a photoetching projection objective, which increases the field size of a projection exposure device and improves the yield.)

1. A photoetching projection objective lens is characterized by comprising a first lens group, a second lens group, a diaphragm, a third lens group and a fourth lens group which are sequentially arranged along an optical axis, wherein the plane of the diaphragm is a diaphragm surface, the first lens group and the fourth lens group are symmetrical relative to the diaphragm surface, and the second lens group and the third lens group are symmetrical relative to the diaphragm surface; the first lens group and the fourth lens group have positive optical power, and the second lens group and the third lens group have negative optical power;

the first lens group and the fourth lens group each include two biconcave negative lenses, two biconvex positive lenses and one meniscus positive lens, and the second lens group and the third lens group each include two meniscus negative lenses, one biconcave negative lens and one biconvex positive lens.

2. Lithography projection objective according to claim 1, wherein all lenses of the lithography projection objective are spherical lenses.

3. Lithography projection objective according to claim 1, wherein the first lens group comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in this order along the optical axis, the first lens and the second lens being double concave negative lenses, the third lens being a meniscus positive lens, the fourth lens and the fifth lens being double convex positive lenses;

the fourth lens group comprises a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens and an eighteenth lens which are sequentially arranged along an optical axis, wherein the fourteenth lens and the fifteenth lens are double convex positive lenses, the sixteenth lens is a meniscus positive lens, and the seventeenth lens and the eighteenth lens are double concave negative lenses;

the concave surfaces of the third lens and the sixteenth lens are deviated from the diaphragm surface.

4. Lithography projection objective according to claim 1, wherein the second lens group comprises a sixth lens, a seventh lens, an eighth lens and a ninth lens arranged in this order along the optical axis, the sixth lens and the seventh lens being meniscus negative lenses, the eighth lens being a biconcave negative lens and the ninth lens being a biconvex positive lens;

the third lens group comprises a tenth lens, an eleventh lens, a twelfth lens and a thirteenth lens which are sequentially arranged along an optical axis, wherein the tenth lens is a double convex positive lens, the eleventh lens is a double concave negative lens, and the twelfth lens and the thirteenth lens are meniscus negative lenses;

the concave surfaces of the sixth lens and the thirteenth lens face the diaphragm surface, and the concave surfaces of the seventh lens and the twelfth lens face away from the diaphragm surface.

5. Lithography projection objective according to claim 4, characterized in that the surface of the lens on the side remote from the stop face is a front surface and the surface of the lens on the side close to the stop face is a rear surface;

at least one meniscus lens exists in the second lens group and the third lens group respectively, and the conditions are as follows: r_L-(R_S+CT)≥10％*R_S，R_L＞R_S；

Wherein R is_LIs the absolute value of the radius of curvature of the front surface of the lens, R_SIs the absolute value of the radius of curvature of the rear surface of the lens and CT is the thickness of the lens.

6. Lithography projection objective according to claim 1, further comprising a first plate and a second plate that are plane-symmetric with respect to the diaphragm;

the first flat plate is located on one side, far away from the diaphragm surface, of the first lens group, and the second flat plate is located on one side, far away from the diaphragm surface, of the fourth lens group.

7. Lithography projection objective according to claim 6, wherein the first lens group comprises a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in this order along the optical axis, the second lens and the third lens being double concave negative lenses, the fourth lens and the fifth lens being double convex positive lenses, the sixth lens being a meniscus positive lens;

the fourth lens group comprises a fifteenth lens, a sixteenth lens, a seventeenth lens, an eighteenth lens and a nineteenth lens which are sequentially arranged along an optical axis, wherein the fifteenth lens is a meniscus positive lens, the sixteenth lens and the seventeenth lens are double-convex positive lenses, and the eighteenth lens and the nineteenth lens are double-concave negative lenses;

the concave surfaces of the sixth lens and the fifteenth lens face the diaphragm surface.

8. Lithography projection objective according to claim 6, wherein the second lens group comprises a seventh lens, an eighth lens, a ninth lens and a tenth lens arranged in that order along the optical axis, the seventh lens and the eighth lens being meniscus negative lenses, the ninth lens being a biconcave negative lens and the tenth lens being a biconvex positive lens;

the third lens group comprises an eleventh lens, a twelfth lens, a thirteenth lens and a fourteenth lens which are sequentially arranged along an optical axis, wherein the eleventh lens is a double convex positive lens, the twelfth lens is a double concave negative lens, and the thirteenth lens and the fourteenth lens are meniscus negative lenses;

the concave surfaces of the seventh lens and the fourteenth lens face the diaphragm surface, and the concave surfaces of the eighth lens and the thirteenth lens face away from the diaphragm surface.

9. A lithographic projection objective according to claim 1, wherein at least one of the five lenses of said first lens group is made of calcium fluoride material, at least one of the five lenses of said first lens group is made of flint glass material, and the lens made of flint glass material has positive power.

10. A lithographic projection objective according to claim 1, wherein at least one of the four lenses of the second lens group is made of a crown glass material, at least one of the four lenses of the second lens group is made of a flint glass material, and the lenses made of the crown glass material have a positive power and the lenses made of the flint glass material have a negative power.

Technical Field

The embodiment of the invention relates to the lithography technology, in particular to a lithography projection objective.

Background

Optical lithography is a technique in which a mask pattern is reproduced by projection with light. Integrated circuits are produced by projection exposure apparatuses. By means of projection exposure apparatus, patterns with different mask patterns are imaged onto a substrate, such as a silicon wafer or an LCD panel, for the manufacture of integrated circuits, thin film magnetic heads, liquid crystal display panels, or a range of structures for micro-electro-mechanical systems (MEMS). The technological level of exposure equipment is continuously developed in the past decades, and the requirements of smaller line size, larger exposure area, higher reliability and yield and lower cost are met.

The existing photoetching projection objective lens has a relatively small field of view, and the problem needs to be solved urgently.

Disclosure of Invention

The embodiment of the invention provides a photoetching projection objective, which increases the field size of a projection exposure device and improves the yield.

The embodiment of the invention provides a photoetching projection objective which comprises a first lens group, a second lens group, a diaphragm, a third lens group and a fourth lens group which are sequentially arranged along an optical axis, wherein the plane where the diaphragm is located is a diaphragm surface, the first lens group and the fourth lens group are symmetrical relative to the diaphragm surface, and the second lens group and the third lens group are symmetrical relative to the diaphragm surface; the first lens group and the fourth lens group have positive optical power, and the second lens group and the third lens group have negative optical power;

the first lens group and the fourth lens group each include two biconcave negative lenses, two biconvex positive lenses and one meniscus positive lens, and the second lens group and the third lens group each include two meniscus negative lenses, one biconcave negative lens and one biconvex positive lens.

Optionally, all lenses in the lithographic projection objective are spherical lenses.

Optionally, the first lens group includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence along an optical axis, the first lens and the second lens are biconcave negative lenses, the third lens is a meniscus positive lens, and the fourth lens and the fifth lens are biconvex positive lenses;

the fourth lens group comprises a fourteenth lens, a fifteenth lens, a sixteenth lens, a seventeenth lens and an eighteenth lens which are sequentially arranged along an optical axis, wherein the fourteenth lens and the fifteenth lens are double convex positive lenses, the sixteenth lens is a meniscus positive lens, and the seventeenth lens and the eighteenth lens are double concave negative lenses;

the concave surfaces of the third lens and the sixteenth lens are deviated from the diaphragm surface.

Optionally, the second lens group includes a sixth lens, a seventh lens, an eighth lens and a ninth lens, which are arranged in sequence along the optical axis, the sixth lens and the seventh lens are meniscus negative lenses, the eighth lens is a biconcave negative lens, and the ninth lens is a biconvex positive lens;

the third lens group comprises a tenth lens, an eleventh lens, a twelfth lens and a thirteenth lens which are sequentially arranged along an optical axis, wherein the tenth lens is a double convex positive lens, the eleventh lens is a double concave negative lens, and the twelfth lens and the thirteenth lens are meniscus negative lenses;

the concave surfaces of the sixth lens and the thirteenth lens face the diaphragm surface, and the concave surfaces of the seventh lens and the twelfth lens face away from the diaphragm surface.

Optionally, the surface of the lens on the side away from the diaphragm surface is a front surface, and the surface of the lens on the side close to the diaphragm surface is a rear surface;

at least one meniscus lens exists in the second lens group and the third lens group respectively, and the conditions are as follows: r_L-(R_S+CT)≥10％*R_S，R_L＞R_S；

Wherein R is_LIs the absolute value of the radius of curvature of the front surface of the lens, R_SIs the absolute value of the radius of curvature of the rear surface of the lens and CT is the thickness of the lens.

Optionally, the lithographic projection objective further comprises a first plate and a second plate that are plane-symmetric with respect to the diaphragm;

the first flat plate is located on one side, far away from the diaphragm surface, of the first lens group, and the second flat plate is located on one side, far away from the diaphragm surface, of the fourth lens group.

Optionally, the first lens group includes a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, which are sequentially arranged along an optical axis, the second lens and the third lens are biconcave negative lenses, the fourth lens and the fifth lens are biconvex positive lenses, and the sixth lens is a meniscus positive lens;

the fourth lens group comprises a fifteenth lens, a sixteenth lens, a seventeenth lens, an eighteenth lens and a nineteenth lens which are sequentially arranged along an optical axis, wherein the fifteenth lens is a meniscus positive lens, the sixteenth lens and the seventeenth lens are double-convex positive lenses, and the eighteenth lens and the nineteenth lens are double-concave negative lenses;

the concave surfaces of the sixth lens and the fifteenth lens face the diaphragm surface.

Optionally, the second lens group includes a seventh lens, an eighth lens, a ninth lens and a tenth lens arranged in sequence along the optical axis, the seventh lens and the eighth lens are meniscus negative lenses, the ninth lens is a biconcave negative lens, and the tenth lens is a biconvex positive lens;

the third lens group comprises an eleventh lens, a twelfth lens, a thirteenth lens and a fourteenth lens which are sequentially arranged along an optical axis, wherein the eleventh lens is a double convex positive lens, the twelfth lens is a double concave negative lens, and the thirteenth lens and the fourteenth lens are meniscus negative lenses;

the concave surfaces of the seventh lens and the fourteenth lens face the diaphragm surface, and the concave surfaces of the eighth lens and the thirteenth lens face away from the diaphragm surface.

Optionally, at least one of the five lenses of the first lens group is made of a calcium fluoride material, at least one of the five lenses of the first lens group is made of a flint glass material, and the lens made of the flint glass material has positive focal power.

Optionally, at least one of the four lenses of the second lens group is made of crown glass material, at least one of the four lenses of the second lens group is made of flint glass material, the lenses made of crown glass material have positive power, and the lenses made of flint glass material have negative power.

The embodiment of the invention provides a photoetching projection objective, wherein light emitted by a light source irradiates a mask plate, a pattern on the mask plate is projected onto a workpiece through the photoetching projection objective, and photoresist coated on the workpiece is exposed. The photoetching projection objective comprises a first lens group and a fourth lens group which are symmetrically arranged about a diaphragm surface, and a second lens group and a third lens group which are symmetrically arranged about the diaphragm surface, and the symmetrical arrangement can compensate asymmetric phase difference in a field and improve the imaging quality. The first lens group includes two biconcave negative lenses, two biconvex positive lenses, and one meniscus positive lens. The second lens group includes two meniscus negative lenses, a biconcave negative lens, and a biconvex positive lens. Since the third lens group is symmetrical to the second lens group with respect to the stop surface, the third lens group also includes two meniscus negative lenses, one biconcave negative lens, and one biconvex positive lens. Since the fourth lens group is symmetrical to the first lens group with respect to the stop surface, the fourth lens group also includes two biconcave negative lenses, two biconvex positive lenses, and one meniscus positive lens. The combination of the first lens group, the second lens group, the third lens group and the fourth lens group increases the view field size of the projection exposure device and improves the productivity.

Drawings

Fig. 1 is a schematic structural diagram of a lithographic projection objective according to an embodiment of the present invention;

FIG. 2 is a wave aberration diagram of the lithographic projection objective shown in FIG. 1;

FIG. 3 is a diagram of the optical transfer function of the lithographic projection objective shown in FIG. 1 at fields of view of 250 cl/mm;

FIG. 4 is a plot of field curvature, astigmatism, of the lithographic projection objective shown in FIG. 1;

FIG. 5 is a distortion diagram of the lithographic projection objective shown in FIG. 1;

FIG. 6 is a schematic structural diagram of a lithographic projection objective according to a second embodiment of the present invention;

FIG. 7 is a wave aberration diagram of the lithographic projection objective shown in FIG. 6;

FIG. 8 is a diagram of the optical transfer function of the lithographic projection objective shown in FIG. 6 at fields of view of 250 cl/mm;

FIG. 9 is a plot of field curvature, astigmatism, of the lithographic projection objective shown in FIG. 6;

fig. 10 is a distortion diagram of the lithographic projection objective shown in fig. 6.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.