KR20030097007A - Manufacturing method for molds of LCD backlight unit using UV photolithography - Google Patents

Abstract

PURPOSE: A method for fabricating a mold of an LCD backlight device by ultraviolet photo etching is provided to obtain a backlight mold with superior surface roughness in various shapes by processing a mold object through ultraviolet photo etching, wherein the reproducibility is very high so that the mass production is realized. CONSTITUTION: A method for fabricating a mold of an LCD backlight device by ultraviolet photo etching includes the steps of doping a positive ultraviolet photosensitive element(20) on a silicon substrate(10) with a thickness of about 30μm through first and second rotation doping, and transferring an ultraviolet mask(30) pattern to the positive ultraviolet photosensitive element by radiating ultraviolet rays(40) to the pattern with inclination, thereby forming a structure with the photosensitive element stick on the substrate. A plating seed layer is formed on the substrate for electroplating, and a metal layer is formed with a predetermined thickness. The mold is finished by removing the substrate and the positive ultraviolet photosensitive element from the metal layer.

Description

Manufacturing method for molds of LCD backlight unit using UV photolithography

The present invention relates to a method for manufacturing a mold for a liquid crystal device backlight device using an ultraviolet photolithography process, and more particularly, an ultraviolet photolithography process for producing a mold having a variety of shapes with excellent surface roughness using the ultraviolet photolithography process. It relates to a mold manufacturing method for a liquid crystal device backlight device using the.

As is well known to those skilled in the art, Liquid Crystal Display (LCD) (hereinafter abbreviated as "LCD") is one of the flat panel display devices and belongs to the passive display device which does not emit light by itself. Passive display elements such as LCDs require a backlight device that generates light at the back or side of the device.

As described above, the LCD, which is a passive display element, requires a backlight device, but most of the light loss in the LCD is generated in the backlight device including a light guide plate, a diffusion plate, a prism, and a reflector. Therefore, the research on the backlight device to realize high brightness and low power consumption by reducing light loss has been widely and variously conducted.

One embodiment of the prior art for the backlight device of the liquid crystal device, using a method of manufacturing a light guide plate formed with an optical pattern by forming a mold by a method such as dot printing method or machine cutting on the back of the light guide plate and have.

1A shows an embodiment of an LCD backlight device which is generally used. Referring to FIG. 1A, a general LCD backlight device includes a long light source 1 disposed on one side of a light guide plate 2. At the bottom of the light guide plate 2, a reflection plate 3 for simultaneously scattering and reflecting light is disposed, and above the light guide plate 2, a plurality of diffusion plates 4 and 4 'and a prism plate 5 and 5 are disposed. ') Is laminated and the LCD panel 6 is mounted thereon.

However, in order for an image to be displayed on the LCD screen evenly and accurately, the intensity distribution of light incident on the LCD panel 6 should be uniformly distributed throughout the LCD panel 6. ) Was subjected to additional processing such as "V" projection or groove shape.

Referring to FIG. 1B, a light guide plate having a “V” groove shape as described above is as follows.

As a representative form of the light guide plate treatment added to make the intensity distribution of light incident on the LCD panel 6 uniform throughout the LCD panel 6, a "V" letter in the form of a prism formed in parallel in the longitudinal direction. Form a groove. In order to manufacture a light guide plate having such a "V" groove, a method of processing a diamond blade is used.

However, as described above, the processing method using the diamond blade is difficult to remove lint and the like generated when forming the fine pattern with the diamond blade and takes a long time to form the pattern.

In addition, optical elements such as reflectors, diffusers, and prisms, as well as light guide plates for liquid crystal device backlights, are arranged in micro-unit structures. The cost of manufacturing the mold is expensive and it is difficult to manufacture a mold having excellent surface roughness.

In addition, recently developed micro mold manufacturing method using the X-ray is difficult to use the X-ray, there is a disadvantage that the manufacturing cost increases because the use fee is expensive.

The technical problem to be achieved by the present invention is to solve the conventional problems as described above, using the ultraviolet photolithography process is excellent in surface roughness, ultraviolet photolithography process that can produce a mold for various types of halo device It is an object of the present invention to provide a mold manufacturing method for a liquid crystal device backlight device.

Another object of the present invention is to provide a mold manufacturing method for a liquid crystal device backlight device using an ultraviolet photolithography process to achieve high reproducibility of the mold process for the liquid crystal device backlight device, and mass production.

Figure 1a is a perspective view showing a backlight device for a generally used LCD,

1B is a view showing a conventional light guide plate configuration,

2a to 2e is a process flow chart of a mold manufacturing method for a liquid crystal device backlight device using the ultraviolet photolithography etching process according to the present invention,

3 is a perspective view of an embodiment of a light guide plate manufactured by a mold manufacturing method for a liquid crystal device backlight device using an ultraviolet photographic etching process according to the present invention,

4A to 4C are plan views of ultraviolet masks used as an embodiment according to the present invention;

5A and 5B are perspective views of the photosensitive material pattern manufactured by the ultraviolet mask of FIGS. 4B and 4C, respectively.

<Description of the code | symbol about the principal part of drawing>

10 substrate 20 positive ultraviolet photosensitive material

30, 32, 34: UV mask 40: UV

50: plating seed layer 60: metal layer

70: mold 80: light guide plate

In order to achieve the above object, a method for manufacturing a mold for a liquid crystal device backlight using the ultraviolet photolithography process according to the present invention includes the steps of: applying a positive ultraviolet photosensitive material on a substrate; Obliquely exposing ultraviolet rays to an ultraviolet mask pattern and transferring the positive ultraviolet photosensitive material; Developing the positive ultraviolet photosensitive material to form a pattern on the substrate; Electroplating a metal layer along a pattern shape on the substrate to form a predetermined thickness; And removing the substrate and the positive ultraviolet photosensitive material to form a mold made of the metal layer.

In a preferred embodiment of the present invention, various molds can be formed according to the angle and direction in which the mold pattern for the liquid crystal device backlight device irradiates light and the pattern of the ultraviolet mask.

In addition, the mold manufacturing method for a liquid crystal device backlight device using the ultraviolet photolithography etching process of another embodiment of the present invention for achieving the above object comprises the steps of applying a positive ultraviolet photosensitive material on the substrate; Obliquely exposing ultraviolet rays to an ultraviolet mask pattern to transfer them to the positive ultraviolet photosensitive material; And developing a light guide plate mold formed by developing the positive ultraviolet photosensitive material to form a pattern on the substrate.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of a mold manufacturing method for a liquid crystal device backlight device using the ultraviolet photolithography etching process according to the present invention. In the following description of the present invention, when it is determined that detailed descriptions of related well-known technologies or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or an operator. Therefore, the definition should be made based on the contents throughout the specification.

2a to 2e is a process flow chart of a method for manufacturing a mold for a liquid crystal device back light device using the ultraviolet photolithography etching process according to the present invention, Figure 3 is a method for manufacturing a mold for a liquid crystal device back light device using the ultraviolet photo etching process according to the present invention. 4A to 4C are perspective views of an ultraviolet mask used as an embodiment according to the present invention, and FIGS. 5A to 5B are manufactured by using the ultraviolet mask of FIGS. 4B and 4C. It is a perspective view of the photosensitive material pattern.

First, referring to FIGS. 2A to 2E, which illustrate a process sequence of a method for manufacturing a mold for a liquid crystal device back light device using an ultraviolet photolithography etching process, the present invention is a method of coating a positive ultraviolet photosensitive material 20 on an upper portion of a substrate 10. Step (see FIG. 2A); Transferring the ultraviolet light 40 to the positive ultraviolet photosensitive material 20 by obliquely exposing the ultraviolet light 40 to the ultraviolet mask 30 pattern (see FIG. 2B); Developing the positive ultraviolet photosensitive material 20 to form a pattern on the substrate 10 (see FIG. 2C); Forming a predetermined thickness by electroplating the metal layer 60 along the pattern shape on the substrate 10 (see FIG. 2D); And removing the substrate 10 and the positive ultraviolet photosensitive material 20 to form a light guide plate mold 70 formed of the metal layer 60 (see FIG. 2E).

In addition, the mold manufacturing method for a liquid crystal device backlight device using the ultraviolet photolithography etching process of another embodiment of the present invention, the step of applying a positive ultraviolet photosensitive material 20 on the substrate 10; Transferring the ultraviolet light 40 to the positive ultraviolet photosensitive material 20 by obliquely exposing the ultraviolet light 40 to the ultraviolet mask 30 pattern; And developing the positive ultraviolet photosensitive material 20 to form a light guide plate mold 70 formed by forming a pattern on the substrate 10.

A process of an embodiment of a mold manufacturing method for a liquid crystal device backlight device using the ultraviolet photolithography etching process according to the present invention configured as described above will be described with reference to FIGS. 2 to 5.

First, referring to FIG. 2A, the positive ultraviolet photosensitive material 20 is coated on the substrate 10. Here, the substrate 10 was made of silicon, and AZ 9260 (trade name) was used as the positive ultraviolet photosensitive material 20. AZ 9260 is a photosensitive material capable of forming a thick layer among positive negative photoresists and is generally used when a thickness of 5 μm or more is desired.

In this embodiment, the positive ultraviolet photosensitive material 20 is applied on the substrate 10 to a thickness of about 30 μm. At this time, since it is difficult to obtain a thickness of 20 μm or more with one coating, the first soft coating is applied for about 80 seconds at 110 ° C. and then the second rotation is applied for 160 seconds at about 110 ° C. Second soft bake to this extent.

Next, as illustrated in FIG. 2B, the ultraviolet rays 40 are obliquely exposed to the ultraviolet mask 30 pattern and transferred to the positive ultraviolet photosensitive material 20. At this time, the bonding of the positive ultraviolet photosensitive material 20 in the region receiving the ultraviolet light 40 is broken so that the photosensitive material 20 attached to the substrate 10 without exposure after the developing process forms a structure.

In the present embodiment, the ultraviolet light 40 having a wavelength of 365 nm was inclinedly exposed so that the exposure amount was 1500 to 2500 mJ / cm 2, and the inclined angles were inclinedly exposed at 45 ° C. and 70 ° C., respectively.

On the other hand, the angle of the inclination angle may be performed at various angles.

Subsequently, when the substrate 10 is placed in a developing solution and developed, as shown in FIG. 2C, portions exposed to the ultraviolet ray 40 and portions not exposed but not attached to the substrate 10 are removed to form a triangular mountain shape. The developer of AZ 9260 is mainly AZ 400K (trade name), and after development, it is rinsed with deionized water. After development, it usually goes directly to the electroplating process, but an additional hard bake process can be used to further cure the photoresist.

On the other hand, the photosensitive material resultant at this time can be used directly as a mold 70 (FIG. 2E), in which case the mold may be deformed if a large pressure is applied at the time of formation. However, when the final material is a rubber (elastomer) series can be manufactured by a method in which pressure is not greatly applied during molding, in this case, the photoresist shape may also be used as the mold 70.

FIG. 2D illustrates a process of forming the metal seed layer 60 to a predetermined thickness after forming the plating seed layer 50 for electroplating on the substrate 10.

2E shows a state in which a mold 70 made of a metal layer 60 is formed by removing the substrate 10 and the positive ultraviolet photosensitive material 20.

The mold 70 as shown in FIG. 2E becomes a mold 70 in which the size of the triangular mountain range becomes smaller along the length direction when the pattern of the ultraviolet mask 30 is the same as that of FIG. 4A.

In the case of the light guide plate 80 (FIG. 3) having the triangular mountain shape as described above, the light source is located next to the backlight device of the LCD that is entered into the notebook. In this case, the light intensity of the light source is far from the light source. In order to compensate for this, the mountain ranges are arranged sparsely or small in order to reduce the brightness near the light source, and form a large one in the distance.

If the mold 70 as shown in FIG. 2E is used, the light guide plate 80 shown in FIG. 3 can be obtained. Here, it will be apparent to those skilled in the art that the mold 70 can manufacture not only the light guide plate 80 for a liquid crystal device back light device but also a reflective plate, a diffusion plate, a prism, and the like.

On the other hand, the manufacturing process has been described as an embodiment for obtaining the shape of the mold 70, it is implemented in various forms of embodiments according to the angle and direction of irradiation of the ultraviolet light 40, and the pattern of the ultraviolet mask.

In order to demonstrate the method of the present invention more specifically, the following examples are shown, but the present invention is not limited thereto.

By using the pattern of the ultraviolet mask 32 of FIG. 4B, a photosensitive material pattern having a continuous triangular mountain range of FIG. 5A can be obtained, and finally, a light guide plate having a reversed phase or the like can be manufactured. By using the pattern of the ultraviolet mask 34 of FIG. 4C, a three-dimensional non-continuous triangle as shown in FIG. 5B can be formed on the photosensitive material.

Therefore, the mold for the liquid crystal device backlight device using the ultraviolet photolithography process is excellent in surface roughness, it is possible to manufacture a variety of molds.

Although the present invention has been illustrated and described with reference to certain preferred embodiments, the present invention is not limited to the above-described embodiments, and a person skilled in the art to which the present invention pertains has the present invention set forth in the claims below. Various modifications may be made without departing from the spirit of the invention.

As described above, the method for manufacturing a liquid crystal device backlight device using the ultraviolet photolithography process according to the present invention is excellent in surface roughness by processing the mold object in the ultraviolet photolithography process, to create a mold for various types of backlight device It provides the benefits of doing so.

In addition, the present invention provides a high reproducibility of the mold process for the liquid crystal device backlight device, and can use the existing semiconductor equipment, etc., thereby mass production, and provides a very low cost unit price.

Although a preferred embodiment of the present invention has been described in detail above, those skilled in the art to which the present invention pertains may make various changes without departing from the spirit and scope of the invention as defined in the appended claims. It will be appreciated that modifications or variations may be made. Therefore, changes in the future embodiments of the present invention will not be able to escape the technology of the present invention.

Claims (4)

In the mold manufacturing method for a liquid crystal element backlight device using an ultraviolet photolithography etching process; Applying a positive ultraviolet photosensitive material on the substrate; Obliquely exposing ultraviolet rays to an ultraviolet mask pattern to transfer them to the positive ultraviolet photosensitive material; Developing the positive ultraviolet photosensitive material to form a pattern on the substrate; Electroplating a metal layer along a pattern shape on the substrate to form a predetermined thickness; And removing the substrate and the positive ultraviolet photosensitive material to form a mold made of the metal layer. The mold manufacturing method of claim 1, wherein the pattern of the mold is configured to form various molds according to an angle and direction of irradiation of light and an ultraviolet mask pattern. In the mold manufacturing method for a liquid crystal element backlight device using an ultraviolet photolithography etching process; Applying a positive ultraviolet photosensitive material on the substrate; Obliquely exposing ultraviolet rays to an ultraviolet mask pattern to transfer them to the positive ultraviolet photosensitive material; And developing the positive ultraviolet photosensitive material to form a pattern on the substrate, wherein the mold for a liquid crystal device back light device using the ultraviolet photolithography process is formed. The mold manufacturing method of claim 3, wherein the pattern of the mold is configured to form various molds according to an angle and direction of irradiation of light and an ultraviolet mask pattern.