KR20060093890A - Method producting stamper - Google Patents

Abstract

The present invention is a method of manufacturing a stamper used for manufacturing a light guide plate, the method uses a wafer of a conductive material as a base plate. As a result, process steps can be reduced as compared with using a glass substrate, and a random pattern can be formed at a lower cost and easier than a glass substrate.

Light guide plate, stamper, wafer, random pattern

Description

Stamper manufacturing method {METHOD PRODUCTING STAMPER}

1 is an exploded perspective view schematically showing a backlight unit structure;

FIG. 2 is a flowchart sequentially illustrating a method of manufacturing a stamper used in manufacturing the light guide plate of FIG. 1; FIG. And

3 to 12 are views sequentially showing the step of manufacturing the stamper of FIG.

Explanation of symbols on the main parts of the drawings

10 wafer 14 metal film

16: release agent 18: first metal

20: master 24: release agent

26: second metal 30: stamper

The present invention relates to a method of manufacturing a stamper used for manufacturing a light guide plate.

In general, a liquid crystal display device is portable as one type of flat panel display element, and has been widely used recently because it has advantages of flat panel, thin film, low power consumption, and high image quality. However, since the LCD does not emit light and modulates the transmitted light only, a backlight unit should be provided at the rear of the LCD. The performance of the LCD is not only the LCD itself but the performance of the backlight used therein. Depends heavily on

The backlight unit which is generally used has a structure in which a reflective sheet, a light guide plate, a diffusion sheet, and a prism are sequentially stacked and arranged as described in Korean Patent Laid-Open Publication No. 1998-75054, and a light source is provided at one side of the light guide plate. The light guide plate is used to provide a path for uniformly scattering and diffusing light emitted from the light source, and various patterns are formed in the light guide plate to obtain a desired light distribution. The light guide plate is mainly manufactured by an injection molding method using a stamper. Generally, the process of manufacturing a stamper includes the process of forming a desired pattern on a base board, and the process of manufacturing a master. The master fabrication is performed by applying photoresist on a patterned base plate, plating a metal and then separating it. However, in general, since the base plate is a glass substrate of non-conductive material, a process of performing silver coating over a predetermined thickness so as to mirror the surface and to perform plating effectively before metal plating is performed. Therefore, stamper production takes a lot of time and money.

In addition, in order to form a random pattern on the upper surface of the light guide plate, a stamper having a random pattern is formed. However, a high technology and a high cost are required to form a random pattern on the glass substrate.

In addition, the base plate is generally uneconomical because it has a size for manufacturing a light guide plate, and a rounded pattern is formed because an etchant is used when performing an etching process to form a pattern.

An object of the present invention is to shorten the time required for the process, and to provide a method for manufacturing a stamper having a desired pattern formed at a low cost.

In order to achieve the above object, a stamper manufacturing method of the present invention provides a base plate having a conductive material, forming an arbitrary pattern on the base plate, plating a first metal on the base plate, Separating the master made of the first metal from the base plate, plating the second metal on the master, and separating the stamper made of the second metal from the master. Providing the base plate having the conductive material preferably includes providing a silicon wafer.

According to one example, the step of forming a random pattern on the base plate comprises the step of forming a random pattern on the base plate. In another example, forming an arbitrary pattern on the base plate may include applying a photosensitive agent on the base plate, providing and exposing a mask having a pattern on the base plate, and exposing the etching gas. Etching the base plate. Etching the base plate using the etching gas may include adjusting an amount of the etching gas provided on the base plate such that the surface of the pattern formed on the base plate has a required surface roughness. .

In addition, the step of attaching a release agent on the base plate before the step of plating the first metal on the base plate and the step of attaching a release agent on the master before the step of plating the second metal on the master Can be provided. In addition, a step of depositing a metal film on the base plate after the step of forming an arbitrary pattern on the base plate may be provided.

In addition, the step of providing a base plate having a conductive material includes the step of providing a base plate having a size of at least two times larger than the size used for manufacturing the light guide plate, and the stamper made of the second metal from the master After separating, cutting the stamper to a size and shape used for manufacturing the light guide plate may be provided.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to FIGS. 1 to 12. The embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Therefore, the shape of the elements in the drawings are exaggerated to emphasize a clearer description.

1 is an exploded perspective view schematically showing a backlight unit 10 according to a preferred embodiment of the present invention. Referring to FIG. 1, the backlight unit 10 includes a light source 200, a light guide plate 100, a reflective sheet 300, a diffusion sheet 400, a prism sheet 500, and a protective sheet 600. The reflective sheet 300, the light guide plate 100, the diffusion sheet 400, the prism sheet 500, and the protective sheet 600 are disposed to face each other sequentially from the bottom up, and the light source 200 is disposed on the light guide plate 100. It is disposed on one side of.

As the light source 200, a light emitting diode, a cold cathode flourescent lamp (CCFL), or an external electrode flourescent lamp (EEFL) may be used. The light guide plate 100 serves to guide light emitted from the light source 200, and converts a cold cathode fluorescent lamp, which is a linear light source, or a light emitting diode, which is a point light source, into a surface light source. The reflective sheet 300 is disposed below the light guide plate 100, and the reflective sheet 300 reflects light leaked to the bottom surface of the light guide plate 100 back to the light guide plate 100 to improve light efficiency. A diffusion sheet 400 is disposed on the light guide plate 100, and the diffusion sheet 400 scatters light emitted from the surface of the light guide plate 100 to uniform the luminance. The prism sheet 500 is disposed on the diffusion sheet 400, and the prism sheet 500 includes a first prism 520 in which the acid is formed in the horizontal direction and a second prism 540 in which the acid is formed in the vertical direction. The first prism 520 and the second prism 540 are arranged to be stacked, and they may be arranged to be interchanged in positions. The prism sheet 500 refracts and condenses the light diffused from the diffusion sheet 400 to improve luminance. The protective sheet 600 is disposed on top of the prism sheet 500 to protect the sheets sensitive to dust or scratches. Among the above-described components, the light guide plate 100 may be made of a material such as a transparent acrylic resin such as polymethyl methacrylate (PMMA), and the light guide plate 100 may use a metal core provided with a stamper 30. By injection molding.

Next, a method of manufacturing a stamper used to manufacture the light guide plate of FIG. 1 will be described with reference to FIGS. 2 to 12. 2 is a flowchart sequentially showing a method of manufacturing a stamper 30 according to an exemplary embodiment of the present invention, and FIGS. 3 to 12 are views showing respective steps. 2 to 12, a base plate 10 is first provided (step S10, FIG. 3). The base plate 10 is made of a conductive material so that plating of a metal material is performed well in a subsequent process. The base plate 10 preferably has a large area so that a plurality of stampers (30a in FIG. 10) used for manufacturing the light guide plate can be simultaneously manufactured. For example, a wafer may be used as the base plate 10, and wafers of various sizes may be used, such as 6 inches, 8 inches, or 12 inches, or larger diameter wafers.

Next, a pattern 12 is formed on the wafer 10 (step S12, FIG. 4). The pattern 12 may be provided in a random shape or may be provided in a regular shape. The pattern 12 is a pattern formed on the upper or lower surface of the light guide plate 100. For example, a random pattern may be formed on the upper surface of the light guide plate 100, and a pattern having a regular shape may be formed on the lower surface of the light guide plate 100. The pattern is formed on the upper surface of the light guide plate, and the pattern 12 may be various methods such as a sand blasting method, a pressing method, or an etching method. The sand blasting method is beneficial when forming a random pattern, and the etching method is advantageous when forming a regular pattern. In general, very advanced techniques are required to form a random pattern on a glass substrate for various reasons such as breakage of the glass substrate. Therefore, it can be manufactured only by some specialized producers and the cost is very expensive. However, since the wafer 10 is used as the base plate 10 in the present embodiment, it is possible to form a random pattern at a very easy and low cost as compared to when using the glass substrate.

As a method for forming a pattern using an etching method, a method similar to a method of forming a circuit pattern on the wafer 10 in a semiconductor manufacturing process may be used. That is, a photoresist is first applied onto the wafer 10, and a mask (not shown) on which a desired pattern is formed is disposed thereon. Thereafter, an exposure process using a light source is used, and a pattern is formed on the wafer 10 using an etching solution or an etching gas. In the case of using the etching solution, although the etching process can be performed at low cost, the pattern is likely to be rounded. Therefore, it is preferable to perform the etching process using the etching gas.

The surface roughness of the pattern formed on the surface of the wafer 10 may be easily adjusted according to the amount of etching gas supplied during the etching process. Since the etching process is performed using the etching gas, the cost may be somewhat increased, but it is economical because a plurality of stampers may be manufactured in one process using the base plate 10 having a sufficiently large size.

When pattern formation is completed on the wafer 10, a process of manufacturing the master 20 is performed. The first metal 18 is plated on the wafer 10 for production of the master 20 (step S18, FIG. 7). Electroplating may be used as the plating of the first metal 18. Since the base plate 10 is a wafer 10 made of a conductive material, unlike the glass substrate made of a non-conductive material, it is not necessary to coat silver on the base plate 10. However, optionally, the metal layer 14 may be thinly coated before the first metal 18 is plated to more effectively plate the first metal 18 on the wafer 10 (step S14, FIG. 5). ). In addition, it is preferable to apply a release agent 16 on the wafer 10 before plating so that the first metal 18, which has been plated, is easily separated from the wafer 10 (step S16, Fig. 6). Nickel or sus (SUS) may be used as the first metal 18. When the plating of the first metal 18 on the wafer 10 is completed, the first metal 18 is separated from the wafer 10 to obtain a master 20 (step S20, FIG. 8). On the master 20, a pattern 22 opposite to the pattern 12 formed on the wafer 10 is formed. That is, the convex portions formed on the wafer 10 are provided as recesses in the master 20.

When the production of the master 20 is completed, a process of manufacturing the stamper 30 is performed. The second metal 24 is plated on the master 20 to prepare the stamper 30 (step S24, FIG. 10). Plating of the second metal 24 may be used, such as electroplating. It is preferable to apply a release agent to facilitate separation of the second metal 24 from the master 20 before plating the second metal 24 (step S22, Fig. 9). Nickel or sus may be used as the second metal 24. When the plating of the second metal 24 on the master 20 is completed, the second metal 24 is separated from the master 20 to obtain a stamper 30. The stamper 30 is provided with a pattern 32 (that is, the same pattern as the pattern formed on the wafer 10) opposite to the pattern 22 formed on the master 20 (step S26).

A stamper 30 having a size larger than twice the size of the stamper 30a used for manufacturing one light guide plate is manufactured. Thus, this is cut to obtain a stamper 30a having a desired size and shape (step S28, Fig. 11).

Since the present invention uses a wafer made of a conductive material as a base plate, it is possible to shorten the number of steps required to produce a stamper as compared to when producing a stamper using a glass substrate as a base plate. In addition, it is possible to form a random pattern on the base plate very easily and inexpensively compared to the case of using a glass substrate.

In addition, since a wafer having a much larger area than that required for manufacturing a light guide plate is used, a plurality of stampers may be manufactured at a time, thereby reducing production costs. In addition, since the etching process is performed using the etching gas, a desired pattern can be formed as compared with the case of using the etching liquid, and the amount of etching gas can be adjusted to provide a stamper having a desired surface roughness.

Claims (10)

In the method for manufacturing a stamper used for manufacturing a light guide plate, Providing a base plate having a conductive material; Forming an arbitrary pattern on the base plate; Plating a first metal on the base plate; Separating the master made of the first metal from the base plate; Plating a second metal on the master; And And separating the stamper made of the second metal from the master. The method of claim 1, The step of providing a base plate having the conductive material comprises the step of providing a silicon wafer. The method according to claim 1 or 2, Forming a random pattern on the base plate comprises the step of forming a random pattern on the base plate. The method of claim 1, Forming an arbitrary pattern on the base plate, Applying a photosensitive agent on the base plate; Providing a mask having a pattern formed on the base plate and exposing the mask; And Stamping the base plate using an etching gas comprising the step of manufacturing a stamper. The method of claim 4, wherein Etching the base plate using the etching gas includes adjusting the amount of etching gas provided on the base plate so that the surface of the pattern formed on the base plate has a required surface roughness. Stamper production method. The method of claim 1, The method, Attaching a release agent on the base plate prior to plating the first metal on the base plate; And attaching a release agent on the master prior to plating the second metal on the master. The method of claim 1, The method further comprises the step of depositing a metal film on the base plate after the step of forming an arbitrary pattern on the base plate. The method according to claim 1 or 2, Providing a base plate having a conductive material includes providing a base plate having at least two times the size compared to the size used for manufacturing the light guide plate, The method further comprises the step of cutting the stamper to a size and shape used for manufacturing the light guide plate after the step of separating the stamper made of the second metal from the master. In the method for manufacturing a stamper used for manufacturing a light guide plate, Providing a base plate of a conductive material; Forming an arbitrary pattern on the base plate; Applying a metal material on the base plate; Applying a release agent on the base plate; Plating a first metal on the base plate; Separating the master made of the first metal from the base plate; Applying a release agent on the master; Plating a second metal on the master; And And separating the stamper made of the second metal from the master. The method of claim 9, The base plate is a silicon wafer, characterized in that the stamper manufacturing method.

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