JP2003257313A - Manufacturing method for shadow mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing through holes without dispersion in a manufacturing method for a shadow mask having through holes in the cross direction of a long belt-like metal material. <P>SOLUTION: According to this manufacturing method for a shadow mask, in an etching process, an exhaust nozzle for an etchant disposed in the central part of the long belt-like metal material is made closer to the surface of the metal material than an exhaust nozzle for an etchant disposed at the end of the metal material is, whereby the pressure of the etchant touching the surface of the metal material in the central part of the metal material is made higher than the pressure at the end of the metal material. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a shadow mask using a long strip-shaped metal material as a raw material by photolithography. 2. Description of the Related Art In the production of a shadow mask, various processes of a photolithography method are performed while a long strip-shaped metal material is transported in a substantially horizontal direction. For example, there are a process of forming a resist layer, a process of performing an exposure process using a photomask, a process of performing a development process, a process of performing an etching process, a process of performing a film removing process, and the like. [0003] The long strip-shaped metal material uses an iron-based material,
Material thickness is about 0.1mm ~ 0.15mm, material width is
A coil shape of about 460 mm to 900 mm is often used. In various processes of the photolithography method, first, a resist resin layer is formed on both surfaces of the metal material. Next, using a photomask (one set for the front surface and one for the back surface) in which a predetermined pattern is formed in advance, the surface of the double-sided resist resin layer is continuously printed and exposed, and then the resist resin layer is developed. Next, both surfaces of the metal material having a predetermined portion exposed from the resist resin layer by a development process are etched. In the etching, a method is generally used in which a metal surface is gradually etched while spraying an etching solution onto the surface of a metal material using a spray etching apparatus shown in FIG. 3A to complete a through hole. The arrangement of the through holes is formed in a grid-like arrangement with a pitch interval of about 0.2 mm. FIG. 3B is a schematic plan view of the etching apparatus. As shown in FIG. 3B, a mechanism is provided in which a plurality of etching liquid supply pipes provided in parallel with the direction of transporting the metal material are provided with nozzles for ejecting the etching solution and swing in a direction perpendicular to the direction of transporting the metal material. The etchant is jetted from the nozzles driven using the nozzle to the surface of the metal material. While the metal material is being conveyed at a constant speed in the conveyance direction, an etching solution is jetted onto the surface of the metal material, so that the metal surface is gradually etched. Each nozzle has a mechanism having a function of adjusting the liquid pressure, monitors the etching rate of the metal material, drops the nozzle pressure if the etching rate of the through hole is high, and drops the nozzle pressure if the etching rate is low. The shape of the through hole is controlled by means for increasing the liquid pressure of the nozzle. After completion of the etching, a film is removed by using a predetermined film removing liquid to remove the resist resin layer. Finally, the long strip-shaped metal material is cut into a sheet according to a predetermined size, and a shadow mask is completed. In the etching process of the above-described photo process method, an etching solution is jetted from a nozzle provided in a liquid pipe arranged in parallel with the transport direction. Here, FIGS. 4A to 4C are schematic diagrams for explaining the progress of the etching of the metal material in the etching process. In general, the etching step is to etch from both sides of the metal material, there is a method of performing an etching process simultaneously on the front and back, or a method of performing an etching process on each side, and which method is used is appropriately selected each time. ing. In the following description,
For simplicity, an example of one-sided processing is described. FIG. 4A is a cross-sectional view of a concave portion formed at the beginning of etching, FIG. 4B shows a shape during etching, and FIG. 4C shows a shape at the time of completion of etching. The long strip-shaped metal material continuously advances in the transport direction.
The shape at each passing point in FIGS. 4A, 4B, and 4C is observed, and the degree of the etching rate is determined by comparing with the through holes in the vicinity to obtain data. In the etching step, the etching solution spills from the end of the long strip-shaped metal material, and the fatigued etching solution easily remains on the surface of the metal material at the center of the metal material. For this reason, the hole diameter of the etching through hole tends to be large at the end and small at the center. For this reason, conventionally, the pressure of the etching solution ejected from the nozzle at the center of the metal material is increased, the pressure of the etching solution ejected from the nozzle at the end is decreased, and the diameters of the through holes are averaged. Is adjusted. However, if there is a difference in the liquid pressure of the etching solution ejected between the adjacent nozzles, a variation in the diameter of the through-hole and a variation in the cross-sectional shape of the through-hole are likely to occur. In recent years, there has been a tendency to increase the number of production systems in which shadow mask patterns are provided in multiple directions in the width direction of a long strip-shaped metal material. For example, in the case of two impositions, the difference in the diameter of the through hole near the center of the metal material and the diameter of the through hole near the end of the metal material is remarkable, and the through hole is incorporated in the color picture tube. In such a case, a quality trouble occurs in which the brightness of the screen occurs. FIG. 5A is a plan view showing an example of a shadow mask. FIG. 5B shows an example of an arrangement with two surfaces. The same pattern is an example of arrangement in two rows in the width direction of the metal material. SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and is intended to produce a through-hole having a small variation in a hole diameter in a width direction of a long strip-shaped metal material. An object of the present invention is to provide a method for manufacturing a mask. According to a first aspect of the present invention, there is provided a method of manufacturing a shadow mask in which etching is performed using an etching solution ejected from a spray nozzle using a photolithography method. At the time of the process, the ejection port of the etching solution arranged at the center of the long strip-shaped metal material to be carried out in a substantially horizontal direction is placed on the surface of the metal material from the ejection port of the etching solution arranged at the end of the metal material. A method of manufacturing a shadow mask, wherein the pressure of an etching solution that comes close to the surface of a metal material at the center of the metal material is higher than the pressure of the edge of the metal material. In the etching process using the photolithography method, there is a method in which an etching solution is jetted from a nozzle provided in a liquid pipe arranged in parallel with the transport direction. In this method, the distance to the surface of the metal material was fixed, and the nozzle pressure was adjusted.
However, the method of the present invention is a method in which the liquid pressure of the nozzle is fixed and the distance from the nozzle outlet to the metal material surface is adjusted. FIG. 1 shows an example of an etching apparatus according to a shadow mask manufacturing method of the present invention.
(A) is a side sectional view, and (b) is a plan view. This will be described in detail with reference to FIG. A resist resin layer 2 is formed on the surface of the metal material 1, exposed using a predetermined pattern mask, and developed to form a pattern image exposing a predetermined metal part on the resist resin layer. On the back surface of the metal material 1, a resist resin layer 2 for preventing etching is formed in advance. A plurality of nozzles 6 are arranged so as to face the upper surface of the surface of the metal material 1. The nozzle has an ejection port for ejecting an etching solution, and the etching solution is sprayed from the ejection port in the form of a shower toward the surface of the metal material 1 so as to be brought into contact therewith, thereby etching the exposed metal surface. 1A, the nozzles 6 (N1, N2, N5, and N6) are located near both ends of the metal material 1, and the long nozzles 12 (N1) are located near the center of the metal material 1.
3, N4,). The distance from the nozzle of the nozzle 6 (N1, N2, N5, N6) to the metal material surface and the length of the long nozzle 12
As is clear from the distance from the (N3, N4,) ejection port to the metal material surface, the distance from the ejection port of the long nozzle 12 (N3, N4,) to the metal material surface is reduced. The pressure of the etching solution supplied from the etching solution pressurizing and supplying device 8 is the same and is supplied to all nozzles. Due to the difference in distance between the nozzle 6 (N1, N2, N5, N6) ejection port and the long nozzle 12 (N3, N4,) ejection port to the metal material surface, the liquid pressure when the etching solution comes into contact with the metal material surface Can be different. Since the long nozzles 12 are closer to each other, the pressure is less attenuated due to the distance, so that when the etching liquid comes into contact with the metal material, the liquid pressure becomes higher and the etching rate becomes higher. FIG. 1B is a plan view of an example of an etching apparatus in the etching step of the present invention. The long strip-shaped metal material is transported in the transport direction,
The etching process is performed by an etching solution spouted from the nozzle in a shower shape and a liquid pressure at the time of contact with the metal material.
The area where the nozzles are arranged is called an etching zone 13, the etching zone starts from the etching start point 9, passes through the etching midpoint 10, and at the etching completion point 11, the hole diameters of all the through holes and the cross-sectional shape thereof Are formed normally and the etching process is completed. FIG. 1B shows an example of a nozzle arranged in the etching zone 13. Adjust the distance between the spout and the surface of the metal material so that the hole diameters of all the through holes and their cross-sectional shapes are properly formed, and adjust the liquid pressure difference when the etchant contacts the metal material surface. Optimize.
As a result, the etching rates are equalized, and at the etching completion point 11, the hole diameters and the cross-sectional shapes of all the through holes are formed normally, and the etching process is completed. FIGS. 4A to 4C show the etching zone 1.
FIG. 3 is an enlarged sectional side view for explaining a process in which a hole diameter of a through-hole and a cross-sectional shape thereof are normally formed in 3. In a method of manufacturing a shadow mask for performing various processes of photolithography, in an etching step, a spout of an etching solution located at a central portion of the long strip-shaped metal material conveyed in a substantially horizontal direction. Is brought closer to the surface of the metal material from the outlet of the etching solution located at the end of the metal material, and the pressure of the etching solution contacting the surface of the metal material at the center of the metal material is reduced by the pressure at the end of the metal material. The production of the shadow mask of the present invention, which is characterized by a higher height, is a method of arbitrarily changing the distance from the nozzle outlet to the surface of the metal material to make the etching rate the same. The distance can be changed by changing the height of the nozzle, for example, by devising a long jig such as a long nozzle, or by changing the position of the nozzle, for example, by changing the equipment. There are cases. Further, in the above-mentioned adjusting method for changing the distance to make the etching rate the same, it is necessary to optimize the arrangement of the nozzles. If the etching solution is insufficient, the number of nozzles is increased, and the distance between the nozzles is adjusted so that the dispersion of the etching solution is averaged over the entire surface of the metal material. Next, the present invention will be described with reference to specific examples. <Embodiment 1> FIGS. 2A and 2B are diagrams for explaining an embodiment of an etching apparatus according to the present invention.
Is a side sectional view, and (b) is a plan view. As shown in FIG. 2A, the nozzle 6 (N
1, N2, N3, N4, N5, N6) are swung within a predetermined angle range in a direction perpendicular to the direction of transport of the metal material. The nozzles N3 and N4 at the center of the metal material were changed to long nozzles 12. The distance from the surface of the metal material 1 to the ejection port of each nozzle is determined by the nozzles N1, N2, N5, N6,
Was adjusted to 200 mm, and the nozzles N3 and N4 were adjusted to 150 mm. Each nozzle was arranged as shown in FIG. The etching liquid pressure supplied from the etching liquid pressurizing device 8 was the same. For example, the pressure was increased to 0.5 MPa. Both ends of the metal material are ejection areas from the nozzle 6, the force when the etching solution comes into contact with the surface of the end of the metal material 1 is actually measured as 3.1 N / cm2, and the center of the metal material is a long nozzle. The force applied when the etching solution came into contact with the surface of the central portion of the metal material 1 was 4.2 N / cm 2. As a result of measuring the through-holes of the shadow mask manufactured under the above manufacturing conditions, there was no variation in the hole diameter at the end and the center of the metal material, and satisfactory results were obtained. In the above-described embodiment, the conditions can be set in a short time by standardizing the shape of the nozzle, particularly the length of the nozzle. Further, the standardization of the diameter of the ejection port of the nozzle in a plurality of stages and the simultaneous change of the ejection amount of the liquid have been made possible by the above-described standardization. By using the manufacturing method of the present invention, the diameter of the through-holes formed at the end and the center of the metal material becomes constant, the cross-sectional shape of the through-holes is averaged, and the transmittance of the through-hole is reduced. Variation has also been greatly improved. As a result, when incorporated in a color picture tube, there is an effect that the brightness of the screen is made uniform and the screen can be prevented from being dark in a certain area.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of an etching apparatus of the present invention, wherein (a)
Is a sectional view, and (b) is a plan view. FIGS. 2A and 2B are drawings illustrating an embodiment of the etching apparatus of the present invention, wherein FIG. 2A is a cross-sectional view and FIG. FIG. 3 is a schematic view of an etching apparatus in an etching step of a conventional photo process method, where (a) is a cross-sectional view,
(B) is a plan view. FIGS. 4A and 4B are partially enlarged cross-sectional views illustrating an example of a through hole of a conventional shadow mask; FIG. 4A is a cross-sectional view at the start of etching; FIG. c) Sectional view at the time of completion of etching. 5A and 5B are partial plan views showing an example of a conventional shadow mask. FIG. 5A is a plan view of the shadow mask, and FIG. 5B is a plan view showing an example of a multi-faceted mask. DESCRIPTION OF SYMBOLS 1 ... Metal material 2 ... Resist resin layer 3 ... Through hole 4 ... Shadow mask 5 ... Through hole arrangement area 6 ... Nozzle 7 ... Hydraulic pressure control valve 8 ... Etching liquid pressurizing device 9 ... Etching start Time position 10: Etching position 11: Etching end position 12: Long nozzle 13: Etching zone

Claims (1)

Claims: 1. A method of manufacturing a shadow mask in which etching is performed using an etching solution ejected from a spray nozzle by using a photolithography method. The ejection port of the etching solution placed at the center of the metal strip is closer to the surface of the metal material than the ejection port of the etching solution placed at the end of the metal material, and the surface of the metal material is placed at the center of the metal material. A pressure of an etching solution in contact with the metal material is higher than a pressure of an end portion of the metal material.