CN113156777B

CN113156777B - A lighting module for maskless exposure

Info

Publication number: CN113156777B
Application number: CN202110463944.2A
Authority: CN
Inventors: 桂立
Original assignee: Suzhou Saiyuan Optical Technology Co ltd
Current assignee: Suzhou Saiyuan Optical Technology Co ltd
Priority date: 2021-04-28
Filing date: 2021-04-28
Publication date: 2023-06-27
Anticipated expiration: 2041-04-28
Also published as: CN113156777A

Abstract

The invention discloses a lighting module for maskless exposure, which comprises a collimating lens group and a converging lens, wherein the collimating lens group comprises first collimating lenses which are sequentially arranged, and the first collimating lenses are concave-convex lenses; the second collimating lens is a biconvex lens; the third collimating lens is a convex-concave lens; the fourth collimating lens is a plano-convex lens; the converging lens is a biconvex lens, and through the design, the illumination module for maskless exposure has the advantages of simple structure, higher light energy transmittance and better illumination uniformity.

Description

A lighting module for maskless exposure

Technical Field

The invention relates to an optical lens, in particular to a maskless exposure lighting module for micro-nano lithography.

Background

In the micro-machining fields of microelectronics, optics, circuit boards and the like, an ultraviolet exposure machine has very important application. The traditional mask type exposure machine uses an exposure mode of a large-size parallel ultraviolet light source and a mask. The existing maskless exposure machine adopts the structures of a light source, a light source collimation system, a DMD chip and a projection module. However, the existing lighting module has a complex structure, low light transmittance and poor lighting uniformity.

Disclosure of Invention

In order to overcome the defects of the prior art, one of the purposes of the invention is to provide a lighting module for maskless exposure, which has the advantages of simple structure, higher light energy transmittance and better lighting uniformity.

One of the purposes of the invention is realized by adopting the following technical scheme:

the illumination module for maskless exposure comprises a collimating lens group and a converging lens, wherein the collimating lens group comprises first collimating lenses which are sequentially arranged, and the first collimating lenses are concave-convex lenses; the second collimating lens is a biconvex lens; the third collimating lens is a concave-convex lens; the fourth collimating lens is a plano-convex lens; the converging lens is a biconvex lens.

Further, the front of the collimating lens group is an object plane, and the rear of the converging lens is an image plane; or the front of the collimating lens group is an image plane, and the rear of the converging lens is an object plane.

Further, the first collimating lens is concave near the object plane and convex near the image plane.

Further, the radius of curvature of the concave surface is greater than the radius of curvature of the convex surface.

Further, the curvature radius of the second collimating lens close to the object plane is larger than that of the second collimating lens close to the image plane.

Further, the third collimating lens is convex near the object plane and concave near the image plane.

Further, the radius of curvature of the convex surface is greater than the radius of curvature of the concave surface.

Further, the fourth collimating lens is a plane near the object plane and a convex surface near the image plane.

Further, the curvature radius of the converging lens close to the object plane is equal to the curvature radius close to the image plane.

Further, the object plane coincides with the DMD chip.

Compared with the prior art, the illumination module for maskless exposure has the advantages of simple structure, higher light energy transmittance and better illumination uniformity.

Drawings

FIG. 1 is a schematic view of an optical path of an illumination module for maskless exposure according to the present invention;

FIG. 2 is a distortion diagram of the illumination module for maskless exposure of FIG. 1;

FIG. 3 is a schematic view of diffuse spots of the illumination module for maskless exposure of FIG. 1;

fig. 4 is an image plane telecentricity curve of the illumination module for maskless exposure of fig. 1.

In the figure: 60. a collimating lens group; 61. a first collimating lens; 62. a second collimating lens; 63. a third collimating lens; 64. a fourth collimating lens; 70. a converging lens.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or be present as another intermediate element through which the element is fixed. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1, an illumination module for maskless exposure according to the present invention includes a collimator lens assembly 60 and a converging lens 70, which are disposed in sequence. The object plane is the light emergent surface of the light homogenizing rod, and the image plane is a DMD chip.

The object plane may be located in front of the collimating lens group 60 and the image plane behind the converging lens 70. If the object plane is located behind the converging lens 70 and the image plane is located in front of the collimating lens group 60, the order of lens arrangement is unchanged and the lens is flipped 180 degrees. Taking the first collimating lens 61 as an example, the first collimating lens 61 is a concave-convex lens, the object plane is located in front of the collimating lens group 60, and when the image plane is located behind the converging lens 70, the first collimating lens 61 is concave near the object plane and convex near the image plane. If the object plane is located at the rear of the converging lens 70, the image plane is located at the front of the collimating lens assembly 60, and after the first collimating lens 61 is turned 180 degrees, the first collimating lens 61 is still concave near the object plane, and is convex near the image plane. That is, the range of the curvature radius of the lens toward the object plane is the same regardless of whether the object plane is located before the collimator lens group 60 or after the converging lens 70, and accordingly, the range of the curvature radius of the lens toward the image plane is the same.

The collimator lens group 60 includes a first collimator lens 61, a second collimator lens 62, a third collimator lens 63, and a fourth collimator lens 64. The first collimating lens 61 is a concave-convex lens, the first collimating lens 61 is a concave surface near the object plane, and is a convex surface near the image plane, and the curvature radius of the concave surface is larger than that of the convex surface. The second collimating lens 62 is a biconvex lens, and the radius of curvature of the second collimating lens 62 near the object plane is larger than the radius of curvature near the image plane. The third collimating lens 63 is a convex-concave lens, the third collimating lens 63 is a convex surface near the object plane, and is a concave surface near the image plane, and the curvature radius of the convex surface is larger than that of the concave surface. The fourth collimating lens 64 is a plano-convex lens, and the fourth collimating lens 64 is a plane near the object plane and a convex near the image plane.

The converging lens 70 is a biconvex lens, and the radius of curvature of the converging lens 70 near the object plane is equal to the radius of curvature near the image plane.

The first collimating lens 61, the second collimating lens 62, the fourth collimating lens 64, and the like are described above, and the first collimating lens, the second collimating lens, and the like are merely for distinguishing the naming manners of the lenses, and do not represent the arrangement order.

Preferably, the range of the curvature radius R of the illumination module for maskless exposure is as follows:

the object side of the first collimating lens 61: 5mm < R <7.5mm, image side of the first collimating lens 61: 4mm < R <6.5mm;

the object side of the second collimator lens 62: 110mm < r <140mm, image side of the second collimator lens 62: 11mm < R <15mm;

the object side of the third collimator lens 63: 8.5mm < R <11mm, image side of third collimator lens 63: 7.5mm < R <9.5mm;

the object side of the fourth collimator lens 64: infinity, the image side of the fourth collimator lens 64: 23mm < R <27mm;

the object side of the converging lens 70: 80mm < r <95mm, image side of the converging lens 70: 80mm < R <95mm.

The lens is made of flint glass or crown glass.

The following describes specific embodiments, and the parameters of the lighting module are as follows:

and (3) carrying out optical detection on the illumination module for maskless exposure, wherein the wavelength of a detection light source is 405nm. Fig. 2 is a distortion chart of an illumination module for maskless exposure, in which the abscissa indicates the magnitude of distortion and the ordinate indicates the variation of field of view, and it can be seen from the chart that the distortion is small. Fig. 3 is a schematic view of diffuse spots of an illumination module for maskless exposure. Fig. 4 is a graph of telecentricity of an image plane of an illumination module for maskless exposure, the abscissa represents a field of view, and the ordinate represents telecentricity, and it can be derived from the graph that the telecentricity curve of the center of the image plane of an exposure lens is within 0.3mrad, and has very good telecentricity.

The NA of the object side of the illumination module for maskless exposure is 0.4, the object height is 3mm, the designed wave band is 405nm, the amplification factor is 7.5 times, and the telecentricity is within 0.3 mrad. The illumination module for maskless exposure has the advantages of simple structure, higher light energy transmittance and better illumination uniformity.

The foregoing examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that, for those skilled in the art, it is possible to make several modifications and improvements without departing from the concept of the present invention, which are equivalent to the above embodiments according to the essential technology of the present invention, and these are all included in the protection scope of the present invention.

Claims

1. A lighting module for maskless exposure, includes collimating lens group and convergent lens, its characterized in that: the collimating lens group comprises first collimating lenses which are sequentially arranged, and the first collimating lenses are concave-convex lenses; the second collimating lens is a biconvex lens; the third collimating lens is a concave-convex lens; the fourth collimating lens is a plano-convex lens; the converging lens is a biconvex lens, the front of the collimating lens group is an object plane, and the rear of the converging lens is an image plane; or the front of the collimating lens group is an image surface, the rear of the converging lens is an object surface, the first collimating lens is a concave surface close to the object surface, a convex surface is close to the image surface, the curvature radius of the concave surface is larger than that of the convex surface, the curvature radius of the second collimating lens is larger than that of the image surface, the third collimating lens is a convex surface close to the object surface, a concave surface is close to the image surface, the curvature radius of the convex surface is larger than that of the concave surface, the fourth collimating lens is a plane close to the object surface, a convex surface is close to the image surface, the curvature radius of the converging lens is equal to that of the image surface, and the object side of the first collimating lens: 5mm < R <7.5mm, image side of the first collimating lens: 4mm < R <6.5mm;

the object side of the second collimating lens: 110mm < R <140mm, image side of the second collimating lens: 11mm < R <15mm;

the object side of the third collimating lens: 8.5mm < R <11mm, image side of the third collimating lens: 7.5mm < R <9.5mm;

the object side of the fourth collimating lens: infinity, image side of fourth collimating lens: 23mm < R <27mm;

object side of the converging lens: 80mm < R <95mm, image side of converging lens: 80mm < R <95mm; the object plane coincides with the DMD chip.