JP2006269385A - Glass scale, and metal mask position alignment method and device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for correctly positioning the positions of respective mask parts when a metal mask 1 with a plurality of the mask parts 2 having multiple openings arranged therein is fixed to a trim-like frame. <P>SOLUTION: This technique is so structured that the respective sides of the metal mask 1 are held by a plurality of tension units 13 and pulled to apply tension to the metal mask 1; a glass scale is previously superposed on the lower side of the metal mask 1; and the positions of the respective mask parts 2 are correctly positioned by adjusting the tension applied by the respective tension units 13 such that the openings of the mask parts 2 of the metal mask 1 in areas indicated by A, B, C and D are correctly superposed on reference marks formed on the glass scale. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes extremely thin and different regions of rigidity, such as a metal mask having a mask portion having a large number of minute openings, which is used for a vapor deposition mask used in an organic EL element manufacturing process. The present invention relates to a technique for fixing a metal mask to a frame-like frame in a flat state without distortion, and in particular, to a method and apparatus for taking a metal mask position alignment when fixing the metal mask to the frame, and a glass scale used therefor.

  Conventionally, vacuum vapor deposition is performed in the manufacture of organic EL elements, and a metal mask having a mask portion having a large number of elongated minute openings that allow vapor deposition is used as the vapor deposition mask. In vapor deposition, the metal mask is attached to a frame having a large rigidity having an opening larger than that of the mask by a magnet or the like. However, in recent years, when the patterning has been miniaturized and the openings formed in the mask portion have become finer and the thickness of the metal mask itself has become thinner, the metal mask is simply attached to a frame-like frame with a magnet or the like. Only by using and fixing, there arises a problem that the mask portion is distorted or sag, and the accuracy of the opening cannot be maintained.

  Therefore, as a result of studies to solve this problem, the applicant of the present invention manufactured each of the four sides of the metal mask even in a multi-sided metal mask having a structure in which a plurality of mask portions are formed with an extremely thin metal plate. Holding the metal mask with a plurality of clamps, applying tension to the metal mask with each clamp, and adjusting the tension for each clamp makes the metal mask flat without wrinkles and sagging, and opens each mask portion. Can be held in a straight line and at a constant pitch, and in this state, the metal mask can be held flat by being tensioned even after the clamp is removed by fixing it to the frame-like frame by spot welding or the like. Therefore, it has been found that a multi-face mask can be held without distortion and sagging by using a frame with a simple structure. Tarumasuku developed a method and apparatus for securing the frame-shaped frame without distortion and sagging state (see JP 2004-311335).

However, it has been found that there are further improvements in this method and apparatus. In other words, when applying tension to each of the four sides of the metal mask and fixing it to the frame, simply adjusting the tension so that there is no distortion or sagging in the metal mask does not necessarily lead to uniform elongation of the metal mask. For this reason, the positions of the plurality of mask portions formed on the metal mask may deviate from proper positions. For example, in the case of a multi-face mask for vapor deposition used for manufacturing an organic EL element, a total pitch of ± 10 μm or less may be required with respect to the position of each mask part, but depending on the tension applied to the metal mask, In some cases, the error becomes large, or the entire arrangement is twisted. To prevent this, a length measuring device that can measure the position of several mask parts with high tension (micron order) in the XY direction (vertical and horizontal directions) with tension applied to the metal mask. It is sufficient to adopt a method in which the tension is adjusted so as to obtain an appropriate position. However, this method has the following problems: (1) the length measuring device is expensive, (2) time is required for length measurement, the work efficiency is poor, and (3) position management cannot be performed at a plurality of locations at once. there were.
JP 2004-31335 A

  The present invention has been made in view of such a situation, and when a tension is applied to a metal mask such as a multi-face mask for vapor deposition so that there is no distortion or sagging, the equipment is less expensive than a length measuring device. And a metal mask position alignment method and apparatus capable of managing the positions of a plurality of locations in the metal mask so as to be at appropriate positions with high accuracy in a shorter time than when using a length measuring device, and It is an object to provide a glass scale used in the method and apparatus.

  The invention according to claim 1 of the present invention for solving the above-mentioned problem provides a glass scale used for position alignment of a metal mask having a large number of openings, and a plurality of the metal masks are formed on the surface of a transparent plate. A plurality of reference marks having a smaller size than the opening are formed to indicate an appropriate position of the opening, and a direction indicating figure indicating a direction toward the reference mark is formed around at least two reference marks. It is a glass scale characterized by being.

  The invention according to claim 2 provides a method of performing metal mask position alignment using the glass scale. That is, the invention according to claim 2 is a tensioning process in which each of the four sides of the metal mask having a large number of openings is held by a plurality of clamps, and tension is applied to the metal mask by each clamp, Before or after applying the tension, refer to the step of positioning the glass scale according to claim 1 at a position close to the lower surface of the metal mask, and the direction indicator graphic of the glass scale visible through the opening of the metal mask. Moving at least one of the metal mask and the glass scale in the vertical and horizontal directions and in the rotational direction, and roughly positioning the plurality of openings so that the openings of the metal mask are aligned with the corresponding fiducial marks on the glass scale. Tension adjustment process to adjust tension by clamping A metal mask position alignment method.

  The invention according to claim 3 provides an apparatus for performing metal mask position alignment using the glass scale described above. That is, the invention according to claim 3 includes a plurality of tension units arranged so as to be able to grip and apply tension to each of the four sides of the metal mask having a large number of openings, and the plurality of tension units. The glass scale according to claim 1, which is disposed at a position close to a lower surface of the metal mask stretched by a tension unit, a transmission illumination device disposed on the lower surface side of the glass scale, and the plurality of tension units An imaging unit that is arranged above the metal mask in a state of being stretched at the top and that images the overlapping portion of the opening of the metal mask and the reference mark of the glass scale, and the tension applied by the plurality of tension units is individually adjusted. A metal mask position alignment device having possible adjustment means.

  According to a fourth aspect of the present invention, a reflecting mirror is disposed in place of the illuminating illumination device disposed under the glass scale in the above-described third aspect of the present invention, and the opening of the metal mask and the reference of the glass scale are arranged. The overlapping portion of the mark is imaged using reflected light.

  The invention according to claim 5 is the metal mask position alignment apparatus according to claim 3 or 4, wherein the glass scale is mounted on an X, Y, θ stage, and the metal mask and the glass are placed on the X, Y, θ stage. In this configuration, coarse positioning with the scale can be performed.

  According to a sixth aspect of the present invention, in the metal mask position alignment apparatus according to the third, fourth, or fifth aspect of the present invention, four image pickup means are provided so that four openings can be picked up simultaneously. is there.

  Since the glass scale of the present invention described above is provided with the reference mark indicating the proper position of the plurality of openings of the metal mask, the plurality of metal masks in the state where the glass scale is positioned under the metal mask. By adjusting the tension applied to the metal mask so that the opening matches the fiducial mark on the glass scale, the distance between the multiple openings can be adjusted to an appropriate value, and the position within the metal mask surface can be accurately determined. Can be aligned. Prior to adjusting the tension applied to the metal mask, the glass scale and the metal mask can be roughly positioned so that the reference mark substantially overlaps the desired opening, so that the tension adjustment work can be facilitated. Although it is preferable, even if the fiducial mark is hidden under the metal mask, it is possible to determine where the fiducial mark is by looking at the direction indicator graphic on the glass scale through other openings around the desired opening. It is possible to estimate, and it is possible to easily and quickly perform the rough positioning so that the reference mark overlaps the desired opening.

  According to the metal mask position alignment method and apparatus of the present invention using the glass scale having the above-described configuration, the glass scale is positioned close to the lower surface of the metal mask in a state where tension is applied to the four sides of the metal mask. The metal mask and the glass scale are roughly positioned with reference to the glass scale direction indication figure visible through the opening, and then the metal mask is applied to the metal mask so that the opening of the metal mask is aligned with the fiducial mark of the glass scale. By adjusting the tension, the position in the metal mask can be aligned with the appropriate position with high accuracy, and alignment can be achieved. For example, when a plurality of mask parts are formed on the metal mask, The position can be positioned at a predetermined position with high accuracy. When performing this alignment, it is only necessary to align the opening of the metal mask with the fiducial mark on the glass scale, making it easy to make judgments, making it easy to adjust the tension of the metal mask, and making adjustments in a short time. It is. Further, since a length measuring device is unnecessary, the function can be satisfied with an inexpensive device, which is economically advantageous.

  The present invention can be applied to any metal mask that needs to be kept flat without distortion or sagging, but is particularly suitable as a multi-face mask for vapor deposition for manufacturing an organic EL element that requires precision. It is preferable to apply to the metal mask to be used. Hereinafter, a preferred embodiment of the present invention will be described by taking a metal mask used as a multi-face mask for vapor deposition in manufacturing an organic EL element as an example. FIG. 1 is a schematic perspective view of a main part of a metal mask position alignment apparatus (hereinafter abbreviated as an alignment apparatus) according to an embodiment of the present invention. FIG. 2 is a schematic side view showing a part of the alignment apparatus in cross section. 3 is a schematic side view of a tension unit provided in the alignment apparatus, FIG. 4 is a schematic plan view showing a plurality of tension units provided in the alignment apparatus and a metal mask held by the tension unit, and FIG. 5 is another embodiment. FIG. 6 is a schematic perspective view showing a metal mask to be handled by these alignment devices and a frame-like frame for fixing the alignment mask, and FIG. FIG. 8 is a schematic perspective view of a vapor deposition mask unit formed by fixing a mask. FIG. 8 is a schematic view of a metal mask and a glass scale. FIG. 9 is a schematic plan view showing an enlarged partial area of each of the metal mask and the glass scale. FIG. 10 is an image of the overlapping area between the opening of the metal mask and the reference mark of the glass scale and displayed on the monitor. FIG. 11A and FIG. 11B are schematic plan views illustrating a state in which rough positioning of the metal mask and the glass scale is performed.

  In FIG. 6, reference numeral 1 denotes a right-sided quadrilateral metal mask used as a vapor deposition mask, which is formed by arranging a plurality of mask portions 2 vertically and horizontally. Each mask portion 2 includes a large number of minute openings 40 (see FIG. 9) that allow vapor deposition. The shape and arrangement of the openings 40 in each mask portion are arbitrary. For example, the elongated slit-like openings are arranged in parallel, and the rectangular (slot-like) openings are arranged in the vertical direction and in parallel. Can be mentioned. Many of the openings 40 formed in the mask portion 2 are used for positioning the metal mask 1 as will be described later. Reference numeral 3 denotes a frame frame having a large rigidity for attaching the metal mask 1, and includes an opening 4 having a size including a region (referred to as an effective region) in which a large number of mask portions 2 of the metal mask 1 are formed. The metal mask 1 is made larger in both the vertical and horizontal directions than the frame 3, and an easy cutting line 5 that can be easily cut by bending is formed at a position substantially corresponding to the outer peripheral edge of the frame 3. The easy cutting line 5 has a strength that can withstand a tensile force applied to the metal mask 1. Although the thickness of the metal mask 1, the dimension of the mask part 2, the dimension of the opening formed in it are not specifically limited, the thickness of the metal mask 1 is typically 30 to 200 μm, and the mask part 2 As for the dimensions, the length is 50 to 70 mm, the width is 30 to 50 mm, the width of the opening 40 is 40 to 100 μm, and the width of the non-porous portion between the openings is 80 to 200 μm.

  1 to 4, an alignment apparatus generally indicated by reference numeral 10 can hold a support base 11 and apply tension to the support base 11 by gripping a plurality of locations on each of the four sides of the metal mask 1. A plurality of tension units 13 arranged as described above are provided.

  As shown in an enlarged view in FIG. 3, each tension unit 13 includes a base member 15, a clamp 17 movably held by the base member 15 via a linear motion guide 16, and a drive for reciprocating the clamp 17. Means 18 and the like are provided. Here, an air cylinder is used as the driving means 18, but a hydraulic cylinder, a servo motor or the like may be used instead of the air cylinder. The clamp 17 is a toggle mechanism that pivots the movable claw 17b to hold the metal mask 1 between the fixed claw 17a, the movable claw 17b, and the movable claw 17b while pressing the movable claw 17b firmly against the fixed claw 17a. And an air cylinder (both not shown). As can be clearly seen from FIG. 4, each tension unit 13 is arranged so that each side of the metal mask 1 can be gripped by a plurality of tension units 13 and tension can be applied to the side in a direction perpendicular thereto. Further, the clamps 17 of the plurality of tension units 13 arranged so as to hold each side of the metal mask 1 are arranged in accordance with the mask part 2 and the non-mask part of the metal mask 1, and accordingly, the metal mask A region extending in the vertical direction and a region extending in the horizontal direction in which one mask portion 2 is formed, and a region extending in the vertical direction and a region extending in the horizontal direction without the mask portion, that is, regions having different rigidity, are separately clamped. It is possible to apply tension by pulling at 17.

  The driving means 18 provided in each of the plurality of tension units 13 has adjusting means (not shown) for individually adjusting the driving force by the driving means so that the tension applied to the metal mask 1 can be individually adjusted. Is provided. More specifically, an air supply pipe is connected to the air cylinder constituting the drive means 18, and a regulator capable of individually adjusting the supply pressure to each air cylinder is provided as an adjustment means in the air supply pipe. It has been. Note that air is supplied to the air supply pipes connected to these air cylinders via a common on-off valve so that the drive means (air cylinders) 18 of all the tension units 13 can be operated simultaneously. A speed controller is also provided in the air supply piping to each air cylinder so that the operation timing of each air cylinder can be adjusted.

  2 and 3, a frame support 20 that supports the frame 3 is provided on the base member 15 of the tension unit 13. The frame support 20 places the frame 3 thereon, thereby positioning the frame 3 at a predetermined position in the horizontal plane, and the upper surface of the frame 3 is held by the clamp 17 and applied to the tension applied to the metal mask 1. It arrange | positions so that it can also position in an up-down direction so that it may become a position which touches substantially.

  Furthermore, the support base 11 is provided with an X, Y, and θ stage 23, and a transmission illumination device 24 and a glass scale 25 are provided on the upper surface thereof. The X, Y, and θ stages 23 can adjust the position of the upper surface on which the illumination device 24 for transmission and the glass scale 25 are mounted in the vertical direction (X direction) and the horizontal direction (Y direction) in a horizontal plane. The position can also be adjusted in the rotation direction (θ direction) with the vertical axis at the center as the center. The transmission illumination device 24 can illuminate the entire surface of the glass scale 25 from below.

  The glass scale 25 is formed by forming a large number of reference marks on the surface of a transparent plate material such as a glass plate so as to indicate an appropriate position of the opening of the metal mask 1, and forming the reference mark on the metal mask 1. By aligning the openings, the metal mask 1 can be in a flat state without distortion or sagging, and the in-plane position of the metal mask 1 can be correctly aligned. Here, the reference marks formed on the glass scale 25 may be provided at positions corresponding to at least a plurality of openings (usually about four openings) used for the position alignment of the metal mask 1. In the embodiment, as shown in FIG. 8, the glass scale 25 is formed with a reference mark portion 42 in which a large number of reference marks are arranged at positions corresponding to the plurality of mask portions 2 of the metal mask 1. .

  FIG. 9 is an enlarged view of a part of the mask part 2 of the metal mask 1 and a part of the reference mark part 42 provided on the glass scale 25 corresponding thereto. As described above, a large number of openings 40 are formed at a predetermined pitch in the mask portion 2 of the metal mask 1. Any of these openings 40 may be used for positioning, but in particular, the opening 40A at the corner (shown with a symbol A to identify the position of the opening) is easy to identify. Therefore, it is suitable for use in positioning, and in this embodiment, the opening 40A is used. In the reference mark portion 42 of the glass scale 25, a reference mark 43 is formed at a position indicating an appropriate position of each opening 40 corresponding to the opening 40 of the mask portion 2, and an opening used for positioning is further provided. Around the reference mark 43A formed corresponding to the portion 40A, a direction indicating figure 44 indicating the direction toward the reference mark 43A is formed. Note that no reference mark is formed in the area where the direction indicating figure 44 is formed.

  The fiducial mark 43 (43A) is made smaller in size both vertically and laterally than the opening 40. With this, the glass scale 25 is in a state where the fiducial mark 43 and the opening 40 are overlapped with each other centered. When the overlapping portion of the reference mark 43 and the opening 40 is imaged from above and displayed on the monitor 45 as shown in FIG. 10 with the transmission illumination device 24 (see FIG. 2) illuminated from below, the opening is displayed. The reference mark 43 enters the inside 40, and a rectangular bright portion 46 appears outside the reference mark 43. It is possible to recognize that the reference mark 43 and the opening 40 are correctly overlapped by visually observing the rectangular bright portion 46 or by recognizing it by image processing. Here, the size of the reference mark 43 with respect to the opening 40 may be, for example, about 130 μm long × 30 μm wide when the opening 40 is 150 μm long × 50 μm wide. As shown in FIG. 11, the direction indicating graphic 44 is arbitrary as long as the direction indicating graphic 44 can recognize the direction in which the reference mark 43 </ b> A is present when the direction indicating graphic 44 is viewed through the opening 40 of the metal mask 1. .

  The reference mark 43A formed on the reference mark part 42 and the surrounding direction indicating figure 44 may be provided for all the reference mark parts 42 formed on the glass scale 25, but this is not restrictive. It is good also as a structure provided only in the area | region corresponding to the opening part to be used. For example, when the position alignment of the metal mask 1 shown in FIG. 8 is performed, the openings (A, B, C, If the position alignment is performed with respect to the opening at the position indicated by D), the position of the other mask portion 2 is often an appropriate position. Therefore, the position alignment may be performed with respect to these openings. The reference mark 43A to be formed and the direction indicating figure 44 around the reference mark 43A are formed on the outermost corner portions (A ′, B ′, C ′, D ′) of the reference mark portion 42 located at the corner of the glass scale 25 shown in FIG. (Position shown in Fig. 5).

  In FIG. 2, the glass scale 25 is arranged so as to be in a very close position, although it is not in contact with the metal mask 1 stretched by the plurality of tension units 13 thereon. Here, the reason why the glass scale 25 is not in contact with the metal mask 1 is to prevent the two from rubbing against each other and scratching. This is to enable simultaneous and accurate imaging of the opening 40 of the metal mask 1. The distance between the glass scale 25 and the metal mask 1 is set to about 50 to 200 μm, preferably about 50 to 100 μm. Instead of fixing the glass scale 25 at the position shown in FIG. 2 in advance, when the metal mask 1 is stretched, the glass scale 25 and the transmission illumination device 24 are kept waiting downward, and the opening of the metal mask 1 is opened. When performing alignment, an appropriate lifting mechanism may be provided so that the glass scale 25 and the transmission illumination device 24 can be raised to bring the glass scale 25 into a position close to the metal mask 1.

  1 and 2, the alignment apparatus 10 further includes a moving table 28 that is held movably horizontally on a side frame 27 fixed to the support table 11, and four images that are held on the moving table 28. Means 30 are provided. The imaging means 30 is capable of simultaneously imaging the reference mark of the glass scale 25 and the opening of the metal mask 1, and a CCD camera is used in this embodiment. The CCD camera 30 is provided at a position where images of the openings at the corners of the mask portion 2 in the areas A, B, C, and D of the metal mask 1 can be simultaneously captured, and the depth of focus is The opening of the metal mask 1 and the reference mark of the glass scale 25 are determined so as to be imaged simultaneously.

  Next, an alignment operation performed by the alignment apparatus 10 having the above configuration will be described. The frame 3 is held by the frame supports 20 of the plurality of tension units 13 in a state where the movable table 28 holding the imaging means 30 is in a standby position outside the plurality of tension units 13 and the glass scale 25 and the like. Then, the metal mask 1 is placed thereon, and the four sides thereof are gripped by the clamps 17 of the plurality of tension units 13. This state is the state shown in FIG. At this time, the metal mask 1 is positioned with respect to the frame 3 using a plurality of positioning pins (not shown). Next, the moving table 28 moves above the glass scale 25 and stops at a predetermined position (see FIG. 2). Next, pressurized air is sent to driving means (air cylinder) 18 connected to each clamp 17 to move each clamp 17 in a direction away from the metal mask 1, and the metal mask 1 is moved in both vertical and horizontal directions by a number of clamps. A small tension is applied so that the metal mask 1 is stretched. Thereafter, the positioning pin is removed so that a large tension can be applied to the metal mask 1 without hindrance. Even if the positioning pins are removed from the metal mask 1, the position of the metal mask 1 with respect to the frame 3 does not change much, and the desired positioning accuracy of the metal mask 1 with respect to the frame 3 is maintained.

  Next, imaging is started by the CCD camera 30, and an image is displayed on the monitor 45 (see FIG. 10). Next, while looking at the monitor 45, the operator adjusts the X, Y, and θ stages 23 to move the glass scale 25 in the X, Y, and θ directions, and four openings 40A used for positioning the metal mask 1. The glass scale 25 is roughly positioned so that the reference mark 43A of the glass scale 25 enters (see FIG. 9). By the way, since the glass scale 25 is disposed under the metal mask 1 and the metal mask 1 is opaque except for the opening, it is formed on the glass scale 25 as shown in FIG. If the reference mark 43A is not in the opening 40A, it is impossible to determine where the reference mark 43A is located without the direction indicating figure 44. For this reason, when the glass scale 25 is moved so that the reference mark 43A enters the opening 40A, it is not known in which direction the glass scale 25 should be moved, and it takes a very long time to roughly position the glass scale 25. On the other hand, in this embodiment, since the direction indicating figure 44 exists around the reference mark 43A, the reference mark 43A is present in any direction by visually recognizing it through the openings 40A, 40, etc. By moving the glass scale 25 on the basis of the information, the reference mark 43A can be roughened so that the reference mark 43A enters the opening 40A as shown in FIG. Positioning can be performed. In addition, when the direction indication graphic 44 is not formed on the glass scale 25 and the reference mark 43 is formed at a position adjacent to the reference mark 43A, the adjacent reference mark 43 enters the opening 40A. However, it may not be recognized that the wrong reference mark 43 is included, but this is confirmed because the direction indicating figure 44 is in the opening 40 adjacent to the opening 40A used for positioning. Thus, it can be recognized that the correct reference mark 43A is located in the opening 40A used for positioning. Thus, the rough positioning can be performed accurately in a short time.

  After the rough positioning, the X, Y, and θ stages 23 are fixed in their positions, and the driving force of the driving means 18 of the plurality of tension units 13 that apply tension to the metal mask 1 is confirmed while checking with the monitor 45. The tension applied to the metal mask 1 is adjusted to match the four openings 40A in the regions A, B, C, and D with the corresponding reference marks 43A. When the four openings 40A coincide with the reference mark 43A, the in-plane position of the metal mask 1 is correctly aligned, and the plurality of mask portions 2 formed on the metal mask 1 are respectively positioned at predetermined positions. . Further, the metal mask 1 is in a flat state without distortion and sagging, and the slits (openings) of the mask part 2 are aligned in parallel. That is, the metal mask position alignment is completed. If necessary, by observing the opening at the desired position and checking whether or not the reference mark 43 is correctly placed therein, it is confirmed that the position alignment is correctly performed in other regions. I can confirm.

  Thereafter, with the tension applied to the metal mask 1, the movable table 28 is returned to the standby position outside the metal mask 1, and the metal mask 1 is spot welded to the frame 3 using a laser or the like (not shown). (See reference numeral 33 in FIG. 4) and fix. Thereafter, the metal mask 1 is removed from the clamp 17, and the peripheral portion of the metal mask 1 is removed using the easy cutting line 5. By the above, as shown in FIG. 7, the vapor deposition mask unit 8 of the structure which fixed the metal mask 1 to the flame | frame 3 can be manufactured.

  In the obtained vapor deposition mask unit 8, the metal mask 1 is kept in a state where there is no distortion or sagging, and the openings of the mask part 2 are accurately aligned in parallel, and the position of each mask part is also predetermined. It is kept within the dimensional accuracy. Thus, by performing vapor deposition using the vapor deposition mask unit 8, it is possible to accurately perform vapor deposition of a fine pattern with multiple faces.

  In the above-described embodiment, the transmission illumination device 24 is provided under the glass scale 25, and the light transmitted through the glass scale 25 and the metal mask 1 is imaged by the CCD camera 30. Although the overlapping state between the opening 42 of the metal mask 1 and the opening 40 of the metal mask 1 is monitored, the imaging by the CCD camera 30 is not limited to the transmitted light, but may be configured to use reflected light by illumination from the surface side. In that case, as shown in FIG. 5, it is preferable to provide a reflecting mirror 35 under the glass scale 25 because the amount of reflected light passing through the opening 40 of the metal mask 1 can be increased.

  In the above-described embodiment, the reference mark portion 42 is formed on the glass scale 25 corresponding to each mask portion 2 of the metal mask 1, and most openings of each mask portion 2 are formed in each reference mark portion 42. Reference marks 43 are formed so as to correspond to 40. With this configuration, the metal mask position alignment can be performed by matching the opening 40 of the mask portion 2 at an arbitrary position with the reference mark 43, and whether or not the position alignment has been correctly performed can be checked. However, the present invention is not limited to this configuration, and the reference mark 43A may be provided only in a desired region of the glass scale 25, and the direction indicating pattern 44 may be provided around the reference mark 43A.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and can be changed as appropriate within the scope of the claims. For example, in the above-described embodiment, when adjusting the tension applied to the metal mask 1, the monitor 45 is used to determine whether or not the opening 40 of the metal mask 1 and the reference mark 43 of the glass scale 25 are correctly overlapped. However, instead of visual observation, a signal from the CCD camera 30 may be processed and determined. In the above embodiment, the CCD cameras 30 are provided at four locations. However, the present invention is not limited to this, and one or two CCD cameras 30 are used, and the CCD cameras 30 are moved to positions to be imaged. The method used may be used. However, if the CCD cameras 30 are provided at four locations as in the illustrated embodiment, the tension adjustment can be performed while monitoring the four openings, and the tension adjustment can be performed easily and promptly. The advantage that can be obtained. Further, in the above-described embodiment, the metal mask 1 is positioned by aligning the openings of the four mask portions 2 with the fiducial marks on the glass scale. However, the mask portions 2 used for alignment are four pieces. For example, when positioning only in the vertical direction or only in the horizontal direction of the metal mask is sufficient, the alignment may be performed using the openings of the two mask portions 2.

  Further, in the above-described embodiment, the glass scale 25 is held on the X, Y, and θ stages 23 in order to perform the rough positioning of the metal mask 1 and the glass scale 25. The tension unit 13 to be held may be held on the X, Y, and θ stages. Further, the rough positioning is not necessarily performed using the X, Y, and θ stages, and a method of performing rough positioning by moving the glass scale 25 or the metal mask 1 by hand may be employed.

The schematic perspective view of the principal part of the alignment apparatus which concerns on embodiment of this invention FIG. 1 is a schematic side view showing a part of the alignment device shown in FIG. Schematic side view of the tension unit provided in the alignment apparatus shown in FIG. FIG. 1 is a schematic plan view showing a plurality of tension units provided in the alignment apparatus shown in FIG. 1 and a metal mask held by the tension units. The schematic side view which shows the alignment apparatus which concerns on other embodiment of this invention in part in a cross section FIG. 1 is a schematic perspective view showing a metal mask handled by the alignment apparatus shown in FIG. 1 and a frame-like frame for fixing the metal mask. Schematic perspective view of a vapor deposition mask unit formed by fixing a metal mask to the frame Schematic plan view of metal mask and glass scale Schematic plan view showing enlarged parts of the metal mask and glass scale. Schematic front view showing a state where the overlapping area of the opening of the metal mask and the fiducial mark on the glass scale is imaged and displayed on the monitor (A), (b) is a schematic plan view explaining the state which performs rough positioning of a metal mask and a glass scale

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal mask 2 Mask part 3 Frame 4 Opening 5 Easy cutting line 8 Deposition mask unit 10 Alignment apparatus 11 Support stand 13 Tension unit 15 Base member 16 Direct motion guide 17 Clamp 17a Fixed claw 17b Movable claw 18 Driving means (air cylinder)
20 Frame support 23 X, Y, θ stage 24 Illumination device for transmission 25 Glass scale 27 Side frame 28 Moving table 30 Imaging means (CCD camera)
33 Spot welded part 40, 40A Opening 42 Reference mark part 43, 43A Reference mark 44 Direction indicator 45 Monitor 46 Bright part

Claims (6)

  A glass scale used for position alignment of a metal mask having a large number of openings, and showing a proper position of a plurality of openings of the metal mask on the surface of a transparent plate material, a plurality of smaller sizes than the openings A glass scale, wherein a reference mark is formed, and a direction indicating figure indicating a direction toward the reference mark is formed around at least two reference marks.   2. Each of the four sides of the metal mask having a large number of openings is held by a plurality of clamps, and a tensioning process for applying tension to the metal mask by each clamp, and before or after applying tension to the metal mask. The glass scale according to claim 1 is positioned at a position close to the lower surface of the metal mask, and at least one of the metal mask and the glass scale with reference to a direction indicating figure of the glass scale visible through the opening of the metal mask. A rough positioning step by moving the metal mask in the vertical and horizontal directions as well as the rotation direction, and a tension adjustment step of adjusting the tension by the plurality of clamps so as to align the plurality of openings of the metal mask with the corresponding reference marks of the glass scale. Metal mask position alignment with Law.   A plurality of tension units arranged so that tension can be applied by holding a plurality of locations on each of the four sides of a metal mask having a large number of openings, and a metal mask stretched by the plurality of tension units The glass scale according to claim 1 disposed at a position close to the lower surface of the glass, a transmission illumination device disposed on the lower surface side of the glass scale, and an upper side of the metal mask stretched by the plurality of tension units A metal mask position alignment apparatus, comprising: an imaging unit that is disposed on the metal mask and that images an overlapping portion of the opening of the metal mask and the fiducial mark of the glass scale; and an adjustment unit that can adjust tension applied by the plurality of tension units. .   A plurality of tension units arranged so that tension can be applied by holding a plurality of locations on each of the four sides of a metal mask having a large number of openings, and a metal mask stretched by the plurality of tension units The glass scale according to claim 1, which is disposed at a position close to the lower surface of the glass scale, a reflecting mirror disposed on the lower surface side of the glass scale, and a metal mask stretched by the plurality of tension units. A metal mask position alignment apparatus comprising: an imaging unit that images an overlapping portion of the opening of the metal mask and the fiducial mark of the glass scale; and an adjustment unit that can adjust tension applied by the plurality of tension units.   5. The metal mask position alignment apparatus according to claim 3, wherein the glass scale is mounted on an X, Y, and θ stage.   The metal mask position alignment apparatus according to claim 3, 4 or 5, wherein four image pickup means are provided so that four openings can be picked up simultaneously.

Images