JP2007335218A - Substrate holder and united structural mask - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve alignment accuracy of a deposition mask and a substrate by reducing the self-weight deflection of the substrate. <P>SOLUTION: A substrate holder 2 for retaining the substrate 3 to be deposited is oppositely arranged to two or more deposition masks 7 having pixel opening parts 7a corresponding to deposition patterns. The substrate holder 2 is provided with a frame body 2a and crosspieces 2b projected from frame side pieces forming the frame body 2a toward the inside of the frame. The crosspieces 2b are arranged in positions where deposited materials from the deposition masks 7 are not passed through. The inside of the frame is partitioned by the frame side pieces forming the frame body 2a and crosspieces 2b to form opening parts 2c for making the deposited materials reach the substrate 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate holder and a combined structure mask used when a thin film is formed by evaporating an evaporant emitted from an evaporation source on a substrate in a vacuum.

  2. Description of the Related Art Conventionally, when manufacturing an organic EL panel, a method of coating a light emitting layer, which is a deposited material, on a substrate using a deposition mask having a pixel opening shape has been adopted.

  As a method for manufacturing such an organic EL panel, a technique is disclosed in which the outer size of the vapor deposition mask is increased in order to perform so-called multiple chamfering (see Patent Document 1). In the technique described in Patent Document 1, a plurality of vapor deposition masks are arranged on a base board and fixed in position, and used as an apparently large vapor deposition mask. In addition, an alignment operation between the substrate and the mask is performed using an apparently large deposition mask, and the light emitting layer is separately applied to the substrate.

JP 2002-305080 A

  By the way, in the manufacturing process of the organic EL panel, it is necessary to hold the substrate in order to keep the distance between the vapor deposition mask and the substrate appropriately. At this time, when glass having a size larger than a certain size is used as the substrate of the organic EL panel, the weight of the substrate increases. For this reason, it is known that when the end portion of the substrate is supported, the center portion of the substrate bends to the maximum value due to its own weight.

  Further, in the alignment operation between the substrate and the vapor deposition mask, alignment marks are arranged in advance on each of the substrate and the vapor deposition mask. In general, the alignment is performed by optically observing the relative positions of the alignment marks arranged on the substrate and the vapor deposition mask.

  However, as described above, when the substrate size is increased, the deflection at the central portion of the substrate is increased. For this reason, in order to prevent the rubbing between the substrate and the vapor deposition mask during the alignment operation, it is necessary to increase the separation distance between the substrate and the vapor deposition mask in accordance with the substrate size.

  If the separation distance is larger than the depth of field of the observation optical system, it becomes impossible to simultaneously observe the alignment mark on the substrate and the alignment mark on the vapor deposition mask during the alignment operation.

  Therefore, first, the substrate and the vapor deposition mask are brought relatively close to each other, and each alignment mark is placed within the depth of field of the observation optical system. Thereafter, the operation of reading the relative position between the substrate and the vapor deposition mask must be repeated many times. Therefore, when the separation distance between the substrate and the vapor deposition mask is large, the tact time in the alignment operation is increased.

  Furthermore, the amount of bending of the substrate differs between the state in which the substrate and the vapor deposition mask are separated from each other and the state in which the substrate is in contact. As a result, the position of the alignment mark on the substrate also varies in proportion to the deflection. Therefore, it is difficult not only to maintain the final alignment accuracy but also to increase the tact time.

  Further, once the substrate and the vapor deposition mask are relatively close to each other, the substrate and the vapor deposition mask may come into contact with each other. When the substrate and the vapor deposition mask come into contact with each other in this manner, there is a possibility that the substrate or the vapor deposition mask is damaged.

  The present invention has been proposed in view of the above-described circumstances, reduces the deflection due to the weight of the substrate, improves the alignment accuracy between the substrate and the vapor deposition mask, and reduces the possibility of contact between the substrate and the vapor deposition mask. For the purpose.

  The substrate holder of this invention is related with the substrate holder for hold | maintaining the board | substrate used as a vapor deposition object by arrange | positioning facing the some vapor deposition mask which has an opening arrangement group corresponding to a vapor deposition pattern. The substrate holder includes a frame and a bar protruding from the frame side constituting the frame toward the inside of the frame. The crosspiece is provided at a position where the vapor deposition from each vapor deposition mask does not pass. The inside of the frame is partitioned by frame sides and crosspieces constituting the frame body, and an opening for allowing the deposited material to reach the substrate is formed.

  The substrate holder of the present invention is provided with a crosspiece protruding from the frame side constituting the frame body into the frame, and the inside of the frame is partitioned by the frame side and the crosspiece to allow the vapor deposition to reach the substrate. Forming part. Therefore, the substrate can be supported from the lower side not only by the frame sides constituting the substrate holder but also by the crosspieces. For this reason, the bending due to the weight of the substrate is reduced, and the alignment accuracy between the substrate and the vapor deposition mask can be improved and the tact time can be shortened.

  Hereinafter, a substrate holder and a combined structure mask according to an embodiment of the present invention will be described with reference to the drawings.

  In the present invention, a plurality of vapor deposition masks are arranged on a mask holder, and a combined structure mask is configured by combining the mask holder and the substrate holder. The substrate holder is provided with a crosspiece for reducing the deflection of the large substrate and enhancing the rigidity of the substrate holder itself. And since the lower surface of a large substrate contacts the upper surface of a crosspiece, the bending by the dead weight of a large substrate can be reduced.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described. FIG. 1 is an exploded perspective view of a combined structure mask according to the first embodiment of the present invention. FIG. 2 is a plan view of the combined structure mask according to the first embodiment of the present invention. FIG. 3 is a side view of the alignment apparatus using the combined structure mask according to the first embodiment of the present invention. FIG. 4 is a side view of the combined structure mask according to the first embodiment of the present invention. In addition, in each following figure, the same code | symbol has shown the same member.

  As shown in FIG. 1, a united structure mask 1 according to the first embodiment of the present invention is a deposition target by arranging a mask holder 5 on which four deposition masks 7 are disposed, and facing the deposition mask 7. A substrate holder 2 for holding the substrate 3 is provided. The united structure mask 1 is used in a vacuum chamber when depositing a deposit on the substrate 3.

  The substrate 3 is made of a substantially rectangular thin plate, and is provided with an alignment mark 4 for alignment with the vapor deposition mask 7. In the example shown in FIG. 1, alignment marks 4 and 4 are provided on the left and right side edges, respectively.

  The substrate holder 2 includes a quadrilateral frame 2a, and crosspieces 2b and 2b are spanned from a substantially central part of each frame side constituting the frame 2a toward a substantially central part of the opposing frame side. ing. The crosspieces 2b and 2b are provided at positions where the vapor deposition material from the respective vapor deposition masks 7 does not pass. The frame 2b and the crosspiece 2b partition the inside of the frame so that the vapor deposition material reaches the substrate 3. An opening 2c is formed. In the example shown in FIG. 1, four openings 2 c are formed corresponding to the four vapor deposition masks 7. When vapor deposition is performed on the substrate 3, the substrate 3 is placed on the upper surface of the substrate holder 2.

  Further, as shown in FIG. 2, the substrate holder 2 includes four openings 2c partitioned by frame sides and bars 2b and 2b constituting the frame 2a. Each partition region of the opening 2 c is formed to be larger than the outer shape of each vapor deposition mask 7. Therefore, the attachment / detachment work of the substrate holder 2 with respect to the mask holder 5 is facilitated, and the possibility of damaging the vapor deposition mask 7 or the substrate holder 2 can be reduced.

  The vapor deposition mask 7 has a pixel opening 7a which is an opening array group corresponding to the vapor deposition pattern. In the example shown in FIG. 1, each pixel mask 7 is provided with four pixel openings 7 a.

  The mask holder 5 has reinforcing ribs 5a in which the thickness of the portion where the vapor deposition mask 7 is not installed in the mask holder 5 is larger than the thickness of the portion where the vapor deposition mask 7 is installed. The reinforcing ribs 5a are provided at both left and right ends of the mask holder 5, respectively. The reinforcing ribs 5a increase the bending rigidity of the mask holder 5 itself and maintain the flatness of each vapor deposition mask 7.

  In addition, alignment marks 6 and 6 are provided on the upper surface of the reinforcing rib 5a at positions corresponding to the alignment marks 4 and 4 provided on the substrate 3, respectively. Therefore, when the substrate 3 is placed on the mask holder 5, the alignment marks 4 and 4 on the substrate 3 and the alignment marks 6 and 6 on the reinforcing rib 5a are matched to perform accurate alignment. .

  As described above, in the first embodiment, the four evaporation masks 7 having the four pixel openings 7 a are arranged on the mask holder 5, thereby functioning as one evaporation mask 7 as a whole. That is, in the first embodiment, the combined structure mask 1 that can manufacture 16 vapor deposition panels is configured by combining the mask holder 5 and the substrate holder 2.

  Next, an alignment operation in the first embodiment of the present invention will be described with reference to FIGS. For ease of explanation, the substrate holder 2 is shown in cross section in FIGS.

  As shown in FIG. 3, two observation optical systems 8 including a CCD camera 9 and a lens 10 are arranged above the substrate 3. The observation optical system 8 and the combined structure mask 1 constitute an alignment apparatus.

  Here, light beams 11 from alignment marks (not shown) provided on the substrate 3 and the mask holder 5 reach the CCD camera 9 via the lens 10. Further, the separation distance S1 between the substrate 3 and the mask holder 5 (reinforcing rib 5a) can be observed within the depth of field by alignment marks (not shown) provided on the substrate 3 and the mask holder 5, respectively. It is set to become.

  In order to perform the alignment operation in the first embodiment, first, the substrate holder 2 is raised in the optical axis direction of the observation optical system 8 by a moving means (not shown), and the substrate 3 is supported from below. . Subsequently, the alignment marks on the substrate 3 and the mask holder 5 are observed while the substrate holder 2 is moved in the surface direction of the substrate 3 by a drive system (not shown) attached to the observation optical system 8. Then, the substrate 3 and the mask holder 5 are moved relative to each other in the plane direction so that the alignment mark 4 on the substrate 3 matches the alignment mark on the mask holder 5.

  At this time, since the substrate 3 is supported from below by the frame 2a and the crosspiece 2b of the substrate holder 2, the alignment operation can be performed in a state where the substrate 3 is not bent by its own weight.

  When the alignment operation is completed, as shown in FIG. 4, first, the substrate holder 2 is lowered in the optical axis direction of the observation optical system (not shown) by the moving means (not shown), and the substrate 3 and the substrate holder 2 are moved. Keep it away. In this state, the substrate 3 is in close contact with the mask holder 5 and the vapor deposition mask 7. Subsequently, when deposition is started, a deposit (not shown) emitted from the evaporation source passes through the deposition mask 7, and a thin film (deposition film) corresponding to the pixel opening shape of the deposition mask 7 is formed on the substrate 3. .

  The combined structure mask 1 according to the first embodiment can be used when manufacturing an organic EL panel. That is, in a vacuum chamber having an evaporation source, the substrate 3 to be deposited is mounted on the substrate holder 2 and the substrate 3 and the combined structure mask 1 are aligned. Thereafter, the R (red), G (green), and B (blue) light emitting layers are separately coated to manufacture an organic EL panel.

  The width of the crosspiece 2b constituting the substrate holder 2 used in the first embodiment is 11 mm. However, the width of the crosspiece 2b can be appropriately changed according to the size of the substrate 3 and the like. . That is, if the crosspiece 2b is deformed by the weight of the substrate 3 and the rigidity does not exceed the depth of field of the observation optical system 8, the width of the crosspiece 2b may be set to another value.

  In the first embodiment described above, the united structure mask 1 used in the vacuum chamber has been described. However, the united structure mask 1 may be used in other environments. That is, even when the combined structure mask 1 according to the first embodiment is used in the atmosphere, the effect in the alignment operation is the same. Furthermore, after performing alignment operation in air | atmosphere, you may vapor-deposit as a vacuum environment.

<Second Embodiment>
Next, a second embodiment of the present invention will be described. FIG. 5 is a side view of a combined structure mask according to the second embodiment of the present invention. FIG. 5 shows a state after the alignment operation is finished.

  The combined structure mask 1 according to the second embodiment is configured by combining a mask holder 5 and a substrate holder 2 as shown in FIG. The mask holder 5 has reinforcing ribs 5a in which the thickness of the portion in the mask holder 5 where the vapor deposition mask 7 is not installed is larger than the thickness of the portion where the vapor deposition mask 7 is installed. The reinforcing rib 5 a is set so that its upper surface is lower than the height of the upper surface of the vapor deposition mask 7 installed in the mask holder 5.

  Therefore, as shown in FIG. 5, after the alignment operation between the substrate 3 and the vapor deposition mask 7 is completed, the substrate 3 is in close contact with the vapor deposition mask 7. Further, a clearance S2 is provided between the substrate 3 and the mask holder 5 (reinforcing rib 5a).

  By providing this clearance S2, only the vapor deposition mask 7 comes into close contact with the substrate 3, and the adhesion between the substrate 3 and the vapor deposition mask 7 becomes better. That is, by setting the height of the reinforcing rib 5a of the mask holder 5 to be always lower than the height of the vapor deposition mask 7, the adhesion failure between the substrate 3 and the vapor deposition mask 7 due to the variation in the height of the reinforcing rib 5a. Can be prevented.

  Note that the clearance S2 is set within a range in which each alignment mark can be observed within the depth of field of an observation optical system (not shown) used for the alignment operation between the substrate 3 and the vapor deposition mask 7. Has been.

<Third Embodiment>
Next, a third embodiment of the present invention will be described. FIG. 6 is a plan view of a substrate holder according to the third embodiment of the present invention. Note that FIG. 6 is partially cut away to show the internal structure of the substrate holder.

  As shown in FIG. 6, the planar shape of the substrate holder 12 of the third embodiment is substantially the same as that of the substrate holder 2 (see FIG. 2) of the first embodiment, but in the third embodiment, The difference is that the cooling means is built in the substrate holder 12. This cooling means is for cooling the frame body 12a and the crosspieces 12b constituting the substrate holder 12, and includes a pipe for moving the refrigerant. That is, the cooling means is constituted by the pipeline 13 and the valve 14, and the flow rate of the refrigerant can be controlled by the opening / closing degree of the valve 14. In FIG. 6, reference numeral 12c denotes an opening.

  By using this cooling means, the substrate holder 12 is brought into close contact with the mask holder (not shown) after the alignment operation is completed, and the temperature rise of the combined structure mask composed of the substrate holder 12 and the mask holder is reduced by the heat radiation from the evaporation source. can do. Further, by uniformly controlling the temperature of the combined structure mask, it is possible to reduce the positional deviation of the pixel opening 7a caused by the thermal expansion of the vapor deposition mask 7 itself. For this reason, the deposition position with respect to the substrate 3 can be stabilized, and film formation can be performed while maintaining good accuracy of the film pattern.

  The cooling means is a technique that can be implemented by providing the pipeline 13 in the space in the thickness direction of the substrate holder 12 constituting the combined structure mask of the present embodiment and in the crosspiece 12b. Therefore, it goes without saying that this cannot be realized with a generally used substrate holder having only a frame or a substrate holder having a nail for holding the substrate.

  In this embodiment, water is used as the refrigerant, but other substances that function as the refrigerant may be used.

  The combined structure mask using the substrate holder 12 according to the third embodiment can be used when manufacturing an organic EL panel. That is, after the alignment operation between the substrate 3 to be deposited and the combined structure mask is performed, the substrate holder 12 is brought into close contact with a part of the mask holder, and the combined structure mask is cooled, whereby the organic EL panel is obtained. Can be manufactured.

<Fourth Embodiment>
Next, a fourth embodiment of the present invention will be described. FIG. 7 is a plan view of a substrate holder according to the fourth embodiment of the present invention. Note that FIG. 7 is partially cut away to show the internal structure of the substrate holder.

  As shown in FIG. 7, the planar shape of the substrate holder 15 of the fourth embodiment is substantially the same as that of the substrate holder 2 (see FIG. 2) of the first embodiment, but in the fourth embodiment, The difference is that a temperature adjusting means is built in the substrate holder 15. This temperature adjusting means is for adjusting the temperature of the frame 15a and the crosspiece 15b, and includes seven cartridge type heaters 16, 17, 18, 19, 20, 21, 22 and connection electrode portions 23, 24. Composed. The temperature can be adjusted by a temperature sensor and a control circuit (not shown) so that the substrate holder 15 has a temperature within the management value. In FIG. 7, reference numeral 15c denotes an opening.

  By using this temperature adjusting means, the substrate 3 is heated to a certain temperature range, and after the alignment operation, the substrate holder 15 is lowered, and the substrate 3 and the vapor deposition mask 7 are brought into close contact with each other to allow vapor deposition. At this time, the substrate 3 can be formed while maintaining the temperature by its own heat capacity and by the heat radiation from the substrate holder 15.

  Depending on the type of deposit, it may be preferable to perform deposition while maintaining the temperature of the substrate 3 in a certain temperature range. Therefore, by using the temperature adjusting means of the present embodiment, it is possible to stabilize the vapor deposition conditions on the substrate 3 and obtain good reproducibility of the film quality.

  The temperature adjusting means is provided with cartridge type heaters 16, 17, 18, 19, 20, 21, 22 in the space in the thickness direction of the substrate holder 15 constituting the combined structure mask of the present embodiment and in the crosspiece 15 b. This is a technology that can be implemented. Therefore, it goes without saying that this cannot be realized with a generally used substrate holder having only a frame or a substrate holder having a nail for holding the substrate.

  The combined structure mask using the substrate holder 15 according to the fourth embodiment can be used when manufacturing an organic EL panel. That is, after performing the alignment operation between the substrate 3 to be deposited and the combined structure mask, the substrate holder 15 is brought into close contact with a part of the mask holder, and the temperature of the combined structure mask is adjusted, whereby the organic EL panel. Can be manufactured.

<Fifth Embodiment>
Next, a fifth embodiment of the present invention will be described. FIG. 8 is a plan view of a substrate holder according to the fifth embodiment of the present invention.

  A substrate holder 25 according to the fifth embodiment is a modification of the substrate holder 2 according to the first embodiment. As shown in FIG. 8, the substrate holder 25 according to the fifth embodiment includes a frame body 25a and four bars 25b protruding from the frame sides constituting the frame body 25a toward the inside of the frame. However, each crosspiece 25b does not reach the frame sides facing each other. That is, the substrate holder 25 according to the fifth embodiment has four bars 25b protruding into the frame body 25a, but the opening 25c of the frame body 25a is completely separated by these bars 25b. It is not connected and is connected in the central part.

  Thus, in the fifth embodiment, the frame body 25a and the four bars 25b can reduce the self-weight deflection of the substrate 3. In the present embodiment, the weight of the substrate holder 25 itself can be reduced by forming the crosspieces 25b so as not to reach the mutually opposing frame sides. For this reason, the effect similar to 1st Embodiment can be acquired after reducing the load of the actuator at the time of alignment operation | movement.

It is a disassembled perspective view of the united structure mask which concerns on the 1st Embodiment of this invention. It is a top view of the united structure mask which concerns on the 1st Embodiment of this invention. It is a side view of the alignment apparatus using the united structure mask which concerns on the 1st Embodiment of this invention. It is a side view of the united structure mask which concerns on the 1st Embodiment of this invention. It is a side view of the united structure mask which concerns on the 2nd Embodiment of this invention. It is a top view which notches and shows a part of substrate holder which concerns on the 3rd Embodiment of this invention. It is a top view which notches and shows a part of substrate holder concerning the 4th Embodiment of this invention. It is a top view of the substrate holder concerning a 5th embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Combined structure mask 2 Substrate holder 2a Frame 2b Crosspiece 2c Opening 3 Substrate 4 Alignment mark 5 Mask holder 5a Reinforcement rib 6 Alignment mark 7 Deposition mask 7a Pixel opening 13 Pipeline 14 Valve 16, 17, 18, 19, 20 , 21, 22 Cartridge type heater 23 Connection electrode

Claims (12)

A substrate holder for holding a substrate to be vapor-deposited, facing a plurality of vapor deposition masks having an opening array group corresponding to the vapor deposition pattern,
The substrate holder includes a frame and a bar protruding from the frame side constituting the frame toward the inside of the frame,
The crosspiece is provided at a position where the vapor deposition from each vapor deposition mask does not pass through,
A substrate holder, characterized in that an inside of the frame is partitioned by a frame side constituting the frame body and the crosspiece, and an opening for allowing the deposited material to reach the substrate is formed.   2. The substrate holder according to claim 1, wherein each partition region of the opening is formed to be larger than an outer shape of each vapor deposition mask.   The substrate holder according to claim 1, further comprising a cooling unit that cools the frame and the crosspiece.   The substrate holder according to claim 3, wherein the cooling means includes a pipe for moving the refrigerant.   The substrate holder according to claim 1, further comprising a temperature adjusting unit configured to adjust a temperature of the frame body and the crosspiece.   The substrate holder according to claim 5, wherein the temperature adjusting means includes a plurality of cartridge type heaters.   A combined structure mask comprising: a mask holder in which a plurality of vapor deposition masks each having an opening arrangement group corresponding to a vapor deposition pattern is disposed; and the substrate holder according to any one of claims 1 to 6.   The mask holder has a portion where the thickness of the portion where the vapor deposition mask is not installed in the mask holder is larger than the portion where the vapor deposition mask is installed in at least two locations, 8. The united structure mask according to claim 7, wherein an alignment mark is provided at the site.   The mask holder has a portion where the thickness of the portion where the vapor deposition mask is not installed in the mask holder is larger than the portion where the vapor deposition mask is installed, and the upper surface of the portion is The combined structure mask according to claim 7 or 8, wherein the combined structure mask is set to be lower than a height of an upper surface of the vapor deposition mask installed in the mask holder.   In a vacuum chamber having an evaporation source, a substrate to be deposited is mounted on a substrate holder, and after alignment of the substrate and the combined structure mask according to any one of claims 7 to 9, A method for producing an organic EL panel, wherein the R (red), G (green), and B (blue) light emitting layers are separately coated.   After performing alignment operation | movement of the board | substrate used for vapor deposition and the said union structure mask using the substrate holder of Claim 3 or 4, this board | substrate holder is closely_contact | adhered to a part of mask holder, and union structure The method of manufacturing an organic EL panel according to claim 10, wherein the mask is cooled.   The method for producing an organic EL panel according to claim 10, wherein the substrate holder according to claim 5 or 6 is used to perform deposition while adjusting the temperature of the substrate to be deposited.

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