KR100840236B1 - Exposure apparatus for preventing halation - Google Patents

Abstract

An exposure apparatus that can prevent halation is disclosed. The apparatus includes a mask having a pattern for defining an exposure area of an object to be exposed, and a substrate stage for supporting the object, with a plurality of vacuum holes for vacuum adsorption of the object. It is characterized in that the corner portion is rounded. Since the scattered light generated from the vacuum hole during the exposure of the negative organic insulating film is not irradiated to the non-exposed area of the negative organic insulating film, halation can be prevented and a desired exposure pattern can be obtained.

Description

Exposure apparatus for preventing halation

1A and 1B are cross-sectional views illustrating generation of scattered light due to a peripheral pattern during exposure of a negative organic insulating layer.

2A and 2B are cross-sectional views illustrating generation of scattered light by vacuum holes of a substrate stage when the negative organic insulating layer is exposed.

3 is a schematic view of an exposure apparatus according to a first embodiment of the present invention.

4A and 4B are cross-sectional views illustrating a method of exposing a negative organic insulating layer using the exposure apparatus of FIG. 3.

5 is a cross-sectional view for describing a method of exposing a negative organic insulating layer using a substrate stage according to a second exemplary embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

100: substrate 105: negative organic insulating film

200: substrate stage 210, 220: vacuum hole

300: mask 350: light source

360: illumination optical system 375: reduction projection optical system

365: illumination light 370, 380: exposure light

TECHNICAL FIELD The present invention relates to an exposure apparatus, and more particularly, to an exposure apparatus capable of preventing halation when exposing a negative organic insulating film.

In today's information society, the role of electronic display devices becomes more and more important, and various electronic display devices are widely used in various industrial fields.

In general, an electronic display device refers to a device that transmits various information to a human through vision. In other words, an electronic display device may be defined as an electronic device that converts electrical information signals output from various electronic devices into optical information signals that can be recognized by human eyes, and serves as a bridge that connects humans and electronic devices. It may be defined as.

In such electronic display devices, liquid crystal displays are thinner, lighter than other display devices, have low power consumption and low driving voltage, and are widely used in various electronic devices because they can display images close to cathode ray tubes. .

Currently, the liquid crystal display device is mainly provided with thin film transistors (TFTs) for forming electrodes on two substrates and switching voltages applied to the respective electrodes, and the thin film transistors have two substrates. It is usually formed in one of them.

BACKGROUND ART Liquid crystal display devices using thin film transistors in the pixel portion are expanding their range from notebook PCs to monitors and small and medium products. Accordingly, in order to fabricate a thin film transistor-liquid crystal display device (TFT-LCD) having high brightness and low power consumption, an aperture ratio of about 60 to 70% needs to be enlarged. To this end, an organic insulating layer having a low dielectric constant is used. Methods of manufacturing high quality thin film transistor-liquid crystal display devices have been developed.

Since the organic insulating film has a lower dielectric constant than the inorganic insulating film, generation of parasitic capacitance between the pixel electrode and the lower metal layer (for example, data wiring) is suppressed so that the pixel electrode overlaps the data line and the gate line, respectively. Can be formed. Therefore, when the organic insulating layer is used, the aperture ratio of the pixel can be improved.

The organic insulating layer can be classified into two types, one is a photo definable organic insulating layer and the other is a non-photo definable organic insulating layer.

Photoresist, a typical photosensitive organic insulating layer, is used in a photolithography process for manufacturing a semiconductor chip or a liquid crystal display device. First, a photoresist is applied onto a silicon substrate or a glass substrate on which predetermined patterns are formed, and then ultraviolet rays are applied to a mask. Or X-rays are exposed to expose a predetermined portion of the photoresist. Subsequently, a portion of the photoresist film having high solubility is removed by development to form an etching mask pattern or an ion implantation mask pattern made of photoresist, or to expose a portion of the underlying layer when the photoresist is applied as an interlayer insulating film Openings, contact holes or via holes are formed.

In general, a photoresist is composed of a resin, a photo-active compound (PAC), a solvent, and a small amount of additives, and a novolac resin system is mainly used. Photoresist such as photoresist is divided into positive type and negative type according to the change of dissolution characteristics caused by exposure. In positive photoresist, the exposed area is dissolved so that the positive image of the mask is transferred. The non-exposed areas are dissolved by the developer to transfer the negative image of the mask.

Negative photoresist tends to have excellent solubility and poor thermal properties and chemical resistance while increasing molecular weight by crosslinking or the like. These negative photoresists can be classified into radically reactive photoresists and chemically amplified photoresists. In the former case, the photoexposure bake (PEB) process is omitted after exposure. In this case, the PEB process is applied. Recently, a negative photoresist applied as an interlayer insulating film of a liquid crystal display device is mainly made of a radical reaction type of an acrylic resin, and thus the PEB process is omitted.

Such a negative organic insulating layer has a disadvantage in that swelling and halation occur during a photolithography process. Swelling is a phenomenon in which a developer penetrates into a polymer and a film swells, and it is being solved to some extent by recent technological developments. Halation is a phenomenon in which a strong light is incident on the photoresist film, a part of which exits the photoresist film, reaches the lower substrate, is reflected from the backside of the substrate, and reaches the photoresist film again to expose the photoresist film. Occurs as

1A and 1B are cross-sectional views illustrating generation of scattered light due to a peripheral pattern during exposure of a negative organic insulating layer.

Referring to FIGS. 1A and 1B, a negative organic insulating layer 14 is coated by spin-coating on a substrate 10 made of silicon or glass on which metal wires 12 are formed. Next, the negative organic insulating film 14 is exposed using the mask 50 in which the pattern for defining the exposure area of the negative organic insulating film 14 is formed. At this time, when the reflected light is nonuniform in a predetermined area where the negative organic insulating film 14 receives light, scattered light A is generated from the reflective surface, which is irradiated in an unspecific direction, causing halation.

For example, when scattered light is generated from the side surface of the metal wiring 12 and the scattered light A is irradiated to the non-exposed region 14a of the negative organic insulating layer 14, a portion of the non-exposed region 14a is formed. It is exposed by the scattered light A. FIG. In the negative organic insulating layer, since the unexposed region is removed by the developer, the negative organic insulating layer of the non-exposed region 14a must be completely removed after the ideal exposure and development process is performed. However, a problem arises in that an undesired organic insulating film remains in the non-exposed region 14a after the development by the scattered light A irradiated into the non-exposed region 14a (see C in FIG. 1B).

In addition, the region where the negative organic insulating layer 14 is first exposed by the incident light irradiated from the mask 50 is secondarily exposed by the reflected light reflected from the surface of the metal wiring 12, thereby remaining metal after development. A step B is generated between the organic insulating film 14 on the wiring 12 and the organic insulating film 14 in the remaining area. However, this step problem can be solved by uniformly applying the negative organic insulating layer 14 to the entire surface of the substrate 10 to a predetermined thickness or more.

2A and 2B are cross-sectional views illustrating generation of scattered light by vacuum holes of a substrate stage when the negative organic insulating layer is exposed.

Referring to FIGS. 2A and 2B, a negative organic insulating layer 24 is coated on a substrate 20 made of silicon or glass by spin-coating. Subsequently, after loading the substrate 20 into the exposure apparatus, the substrate 20 is vacuum-adsorbed onto the substrate stage 60 having the plurality of vacuum holes 65. Then, the negative organic insulating film 24 is exposed using a mask 60 in which a pattern for defining an exposure area of the negative organic insulating film 24 is formed.

In this case, scattered light D is generated from the vacuum hole 65 of the substrate stage 60 in an unspecified direction, and the scattered light D exposes a part of the negative organic insulating film 24 in the non-exposed area 24a. Let's do it. Then, a halation phenomenon in which an unwanted organic insulating film remains in the non-exposed area 24a after development is caused by the scattered light D irradiated to the non-exposed area 24a (see E in FIG. 2B).

Accordingly, an object of the present invention is to provide an exposure apparatus that can prevent halation during exposure of a negative organic insulating film.

In order to achieve the above object of the present invention, the present invention is a mask that is formed with a pattern for defining the exposure area of the object to be exposed; And a substrate stage having a plurality of vacuum holes for vacuum-adsorbing the exposed object and supporting the exposed object, wherein the vacuum hole is rounded at a corner thereof.

In addition, the above object of the present invention is a mask in which a pattern for defining an exposure area of an object to be exposed is formed; And a substrate stage having a plurality of vacuum holes for vacuum-adsorbing the exposed object and supporting the exposed object, wherein the vacuum hole is formed in a width smaller than the thickness of the exposed object. Can be.

According to the present invention, when the negative organic insulating layer is patterned by a photolithography process in order to apply the negative organic insulating layer to a semiconductor device or a liquid crystal display as a mask pattern or an interlayer insulating layer, a photosensitive negative organic layer coated on a silicon substrate or a glass substrate The corner portion of the vacuum hole of the substrate stage provided in the exposure apparatus for exposing the insulating film is rounded or the vacuum hole is finely processed.                     

Therefore, since the scattered light generated from the vacuum hole during the exposure of the negative organic insulating layer is not irradiated to the non-exposed region of the negative organic insulating layer, the halation phenomenon can be prevented to obtain a desired exposure pattern.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a schematic view of an exposure apparatus according to a first embodiment of the present invention.

Referring to FIG. 3, the exposure apparatus of the present invention includes a light source 350, an illumination optical system 360, a mask 300 on which a pattern for defining an exposure area of an object to be exposed is formed, a reduced transparency optical system 375, and a pino. The substrate stage 200 which supports the silicon or glass substrate 100 to which minerals, ie, the negative organic insulating film 105, is apply | coated is provided.

Light ray 355 emitted from light source 350 is directed to illumination optics 360 by means of directional optics (not shown), for example, having a predetermined light intensity distribution, orientation distribution and numerical aperture NA. It is transformed into the illumination light 365.

The illumination light 365 thus formed illuminates the mask 300, and the mask 300 has patterns made of chromium, for example, formed on a quartz substrate. The pattern has a size corresponding to the inverse of the projection magnification of the reduction projection optical system 375 with respect to the size of the pattern to be formed on the substrate 100.

The illumination light 365 is diffracted through the mask 300 to form the exposure light 370 on the object side.                     

The reduced projection optical system 375 transforms the object side exposure light 370 into the image side exposure light 380 to form an image of the mask 300 on the substrate 100 at the projection magnification. That is, the image side exposure light 380 is collected on the substrate 100 at a predetermined numerical aperture NA, thereby forming an image of the pattern on the substrate 100.

Since the substrate stage 200 moves stepwise along the top surface of the reduction projection optical system 375, patterns are sequentially formed on different regions on the substrate 100. Therefore, the substrate stage 200 displaces its position with respect to the reduction projection optical system 375.

In the substrate stage 200, a plurality of vacuum holes 210 are formed to vacuum-adsorb the substrate 100. According to the present embodiment, the corner of the vacuum hole 210 is rounded. When a portion of the image-side exposure light 380 incident to the substrate 100 exits the substrate 100 and reaches the substrate stage 200 below it and is reflected from the substrate stage 200, the vacuum hole ( Scattered light reflected from the rounded edge of 210 is irradiated downward rather than upward. Accordingly, a halation phenomenon in which the reflected light reaches the negative organic insulating layer 105 on the substrate 100 and exposes the negative organic insulating layer 105 during exposure does not occur.

4A and 4B are cross-sectional views illustrating a method of exposing a negative organic insulating layer using the exposure apparatus of FIG. 3.

Referring to FIG. 4A, a negative organic insulating layer 105 is uniformly coated to a predetermined thickness on a substrate 100 such as a silicon substrate of a semiconductor device or a glass substrate of a liquid crystal display by a spin-coating method. Subsequently, after loading the substrate 100 into the exposure apparatus of FIG. 3, the substrate 100 is vacuum-adsorbed onto the substrate stage 200 having the plurality of vacuum holes 210.

Subsequently, the negative organic insulating layer 105 is exposed through a mask 300 in which a light ray generated from a light source of the exposure apparatus defines a exposure area of the negative organic insulating layer 105.

At this time, since the corners of the vacuum hole 210 of the substrate stage 200 are rounded, the scattered light F reflected from the portion is irradiated downward rather than upward, so that the negative organic light on the substrate stage 200 is negative. It cannot reach the insulating film 105.

Referring to FIG. 4B, since the scattered light F reflected from the vacuum hole 210 of the substrate stage 200 does not reach the negative organic insulating layer 105, the non-exposed area ( The halation phenomenon in which a part of the negative organic insulating film 105 in 105a is exposed does not occur.

Therefore, when the non-exposed region 105a of the negative organic insulating layer 105 is removed through the development process, the negative organic insulating layer of the non-exposed region 105a is completely removed to obtain a desired exposure pattern.

5 is a cross-sectional view for describing a method of exposing a negative organic insulating layer using a substrate stage according to a second exemplary embodiment of the present invention.

Referring to FIG. 5, the vacuum hole 220 of the substrate stage 200 according to the present exemplary embodiment may have a width smaller than a thickness t of a substrate 100 such as a silicon substrate of a semiconductor device or a glass substrate of a liquid crystal display device. w).

After the negative organic insulating layer 105 is uniformly applied to a predetermined thickness on the substrate 100 by a spin-coating method, the substrate 100 is loaded into an exposure apparatus and a vacuum hole in the form of a micro hole ( The substrate 100 is vacuum adsorbed onto the substrate stage 200 having 220.

Subsequently, when the exposure process is performed using the mask 300 on which the pattern for defining the exposure area of the negative organic insulating layer 105 is formed, light incident on the negative organic insulating layer 105 is lowered to the substrate 100. And uniformly reflected from the substrate stage 200.

In addition, even though incident light is irradiated to the vacuum hole 220 of the substrate stage 200, since the size of the vacuum hole 200 is very fine, scattered light reflected from the vacuum hole 200 is upward, that is, the negative organic insulating layer 105. Cannot be investigated.

Therefore, since the negative organic insulating film of the non-exposed region 105a is completely removed by the developing step, a desired exposure pattern can be obtained.

As described above, according to the present invention, when the negative organic insulating film is patterned by a photolithography process in order to apply the negative organic insulating film to a semiconductor device or a liquid crystal display as a mask pattern or an interlayer insulating film, it is applied on a silicon substrate or a glass substrate. The corner portion of the vacuum hole of the substrate stage provided in the exposure apparatus for exposing the exposed photosensitive negative organic insulating film is rounded or the vacuum hole is finely processed. Therefore, since the scattered light generated from the vacuum hole during the exposure of the negative organic insulating layer is not irradiated to the non-exposed region of the negative organic insulating layer, the halation phenomenon can be prevented to obtain a desired exposure pattern.

As described above, although described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and modified within the scope of the present invention without departing from the spirit and scope of the present invention described in the claims below. It will be appreciated that it can be changed.

Claims (11)

A mask in which a pattern for defining an exposure area of an object to be exposed is formed; And A substrate stage having an adsorption hole for vacuum adsorption of the target object and supporting the target object, And the suction hole is rounded at a corner thereof. The exposure apparatus according to claim 1, wherein the exposed object is an insulating substrate of a liquid crystal display device on which a photosensitive film is applied. The exposure apparatus of claim 2, wherein the photosensitive film is made of a negative organic material. The exposure apparatus according to claim 1, wherein the exposed object is a silicon substrate of a semiconductor device to which a photosensitive film is applied thereon. The exposure apparatus according to claim 4, wherein the photosensitive film is made of a negative organic material. The exposure apparatus according to claim 1, wherein the adsorption hole is formed to have a width smaller than the thickness of the object to be exposed. delete delete delete delete A mask in which a pattern for defining an exposure area of an object to be exposed is formed; And When the target object is supported and the target object is supported, the exposure light passing through the mask and the target object from outside while being vacuum-adsorbed to the target object is prevented from being reflected to the non-exposed area outside the exposure area. An exposure apparatus comprising a substrate stage having a suction hole.

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