JP2021014056A - Mask printing machine and displacement acquisition method - Google Patents

Abstract

To acquire displacement in a horizontal direction between a through hole formed on a mask and a pattern formed on a circuit board.SOLUTION: In a mask printing machine, a mask is imaged from above by an imaging device in a state that the mask having a plurality of through holes and a circuit board having a plurality of patterns are overlapped. Although an outline of the pattern formed on the board cannot be seen from above the mask originally, a part of the pattern can be seen through the through holes of the mask in some cases when the mutually corresponding through holes and patterns are displaced in a horizontal direction. A relative position to the through holes of the patterns can be estimated on the basis of the captured image and a previously stored entire shape of the patterns, and displacement in the horizontal direction between the patterns and the through holes can be acquired.SELECTED DRAWING: Figure 12

Description

The present invention relates to a mask printing machine that prints a viscous fluid on a circuit board via a mask, and a deviation acquisition method for acquiring a deviation between a through hole formed in the mask and a pattern formed in the substrate.

In the mask printing machine described in Patent Document 1, the circuit board (hereinafter, simply abbreviated as the substrate) can enter between the mask and the substrate in a state of being separated from the mask below the mask. The first imaging unit images a mask mark, which is a recognition mark provided on the mask, and a clamp mark, which is a recognition mark provided on a clamp member that clamps the substrate from both sides, and based on the captured image, the substrate is imaged. The position correction value at the time of separation, which is the amount of movement of, is acquired. Further, the mask mark and the clamp mark are imaged by the second imaging unit that can enter above the mask while the substrate is in the contact position in contact with the mask, and based on the captured image, they are imaged. The overlapping state is acquired, and the contact position correction value, which is the amount of movement of the substrate, is acquired and stored. After that, at the separation position of the substrate, the substrate is moved based on the separation position correction value acquired based on the image captured by the first imaging unit and the stored contact position correction value, and the substrate is moved. And the mask are aligned. As a result, it is possible to eliminate the misalignment between the substrate and the mask due to the mechanical error of the substrate elevating device that elevates the substrate, and to align the substrate and the mask with high accuracy.

Japanese Unexamined Patent Publication No. 2013-18122

Problems to be solved

An object of the present invention is to obtain a horizontal deviation between a through hole formed in a mask and a pattern formed in a circuit board.

Means, actions and effects to solve problems

In the mask printing machine according to the present invention, the mask is imaged from above by the image pickup apparatus in a state where the mask having a plurality of through holes and the circuit board having a plurality of patterns are overlapped with each other. When the horizontal deviation between the through holes corresponding to each other and the pattern is small, the pattern formed on the substrate cannot be seen from above the mask. However, when the horizontal deviation between these through holes and the pattern is large, a part of the pattern may be visible through the through holes of the mask. Therefore, based on this captured image and the information representing the overall shape of the pattern, it is possible to estimate the relative position of the pattern with respect to the through hole, and it is possible to obtain the horizontal deviation between the pattern and the through hole. it can.

It is a front view of the mask printing machine which concerns on this invention. It is a side view of the said mask printing machine. It is a side view which shows the substrate holding apparatus of the said mask printing machine. It is a top view which shows the substrate moving apparatus of the said substrate holding apparatus. It is a top view which shows the mask moving apparatus of the mask holding apparatus of the said mask printing machine. It is a top view which shows the 2nd image pickup apparatus of the said mask printing machine. It is a block diagram conceptually showing the periphery of the control device of the mask printing machine. It is a figure which shows the state which the substrate is separated from the mask in the said mask printing machine. It is a figure which shows the state which the substrate is in contact with a mask in the said mask printing machine. It is a figure which conceptually shows the captured image in the state which the substrate is in contact with a mask in the said mask printing machine. It is a figure which conceptually shows the captured image of another state in the said mask printing machine. (a), (b) It is a figure which conceptually shows the estimation method of the reference position of a pattern in the said mask printing machine. (a) It is a figure which conceptually shows the relative position of a through hole and a template in the said mask. (b) It is a figure which conceptually shows the state such as the deviation between the through hole and a pattern. It is a flowchart which shows the deviation reliance correction vector acquisition program stored in the storage part of the control device of the mask printing machine. It is a flowchart which shows a part (S6) of the said deviation-based correction vector acquisition program. It is a flowchart which shows another part (S9) of the said deviation-based correction vector acquisition program. (a) and (b) are diagrams conceptually showing through-hole information and pattern information stored in the storage unit of the control device of the mask printing machine.

Embodiments for carrying out the present invention

Hereinafter, the mask printing machine according to the embodiment of the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 to 3, this mask printing machine prints creamy solder as a viscous fluid on a circuit board (hereinafter abbreviated as a board) P via a mask S, and transports the frame 2 and the board. It includes a device 4, a board lifting device 6, a board moving device 8, a mask device 10, a squeegee device 12, a first imaging device 14 as an imaging device, a second imaging device 16, and the like.

The substrate transfer device 4 conveys the substrate P, and includes, for example, a pair of conveyors 20a and 20b, a transfer motor (not shown) for driving the pair of conveyors 20a and 20b, and the like. Hereinafter, in the present specification, the transport direction of the substrate P is the x direction, the width direction which is the direction orthogonal to the transport direction of the substrate P is the y direction, and the thickness direction of the substrate P, that is, the vertical direction of the mask printing machine. Is the z direction. The x-direction, y-direction, and z-direction are orthogonal to each other. Further, as shown in FIGS. 8 to 10 and the like, a plurality of patterns C representing the printed portion of the cream-like solder are formed on the substrate P.

The board lifting device 6 moves (lifts) the board P held by the board holding device 22 as a circuit board holding device in the z direction, and the board moving device 8 moves (lifts) the board held by the board holding device 22. It moves P in the xy plane.

The board holding device 22 includes a plurality of support pins 26 attached to the support plate 24, a clamp device 28, a board holding device 30, and the like. The plurality of support pins 26 support the substrate P from below. The clamp device 28 holds the substrate P from both sides in the width direction (y direction), and provides an approach / separation device 36 or the like that brings the pair of clamp members 34a and 34b and the pair of clamp members 34a and 34b close to and separate from each other. Including. The substrate pressing device 30 includes a pair of pressing members 40a, 40b, an approaching / separating device 41 that brings the pair of pressing members 40a, 40b closer to each other and separated from each other. The height of the upper surface of the substrate P is defined by abutting the upper surfaces of the pair of clamp members 34a and 34b and the upper surface of the substrate P on the lower surfaces of the pair of pressing members 40a and 40b.

The board lifting device 6 includes a first lifting device 46, a second lifting device 47, a third lifting device 48, and the like. The first elevating device 46 includes an electric motor 54, a screw mechanism 56 as a motion conversion mechanism that converts the rotation of the electric motor 54 into a linear movement in the z direction and transmits the rotation to the base 55, and includes a support plate 24 and a clamping device. 28, the first elevating table 57 that supports the substrate holding device 30 and the like is moved up and down together with the base table 55. The second lifting device 47 converts the movement of the piston rods of the air cylinder 62 and the air cylinder 62 in the y direction into movement in the z direction and transmits the movement to the second lifting table 60 as a pair of cam mechanisms 63a. , 63b, etc., and the second lift 60 that supports the support plate 24 and the clamping device 28 is moved up and down with respect to the first lift 57. The third elevating device 48 is a screw mechanism 65 as a motion conversion mechanism that converts the rotations of the electric motor 64 and the electric motor 64 fixed to the second elevating table 60 into linear movement in the z direction and transmits the rotation to the support plate 24. The support plate 24 is moved up and down with respect to the second elevating platform 60, including the above.

The substrate moving device 8 moves the first elevating table 57 with respect to the base base 55 in the xy plane, and includes the x moving device 70 and the two y moving devices 71 and 72 as shown in FIG. .. The y moving devices 71 and 72 are provided at portions of the first elevating platform 57 facing each other in the x direction. Since the x-moving device 70 and the y-moving devices 71 and 72 have the same structure, the x-moving device 70 will be described as a representative. The x-moving device 70 includes an electric motor 74, a moving member 75, a screw mechanism 76 as a motion conversion device that converts the rotation of the electric motor 74 into linear movement of the moving member 75, and the like, which are attached to the base base 55. A protrusion 79 provided on the 75 so as to be integrally movable with the first elevating platform 57 is engaged with the roller 77 via a roller 77 and a ball plunger 78. By driving the electric motor 74, the moving member 75 is moved in the x direction, and the projecting portion 79 and the first elevating base 57 are moved relative to the base base 55 in the x direction. The y-moving devices 71 and 72 are operated in different states and the x-moving device 70 is operated, so that the first elevating table 57 is rotated about the z-axis with respect to the base table 55. The relative movement of the first lift 57 with respect to the base 55 is smoothly allowed by the plurality of steel balls 58 (see FIG. 3) interposed between the first lift 57 and the base 55.

The mask device 10 is provided above the substrate elevating device 6 and the like of the frame 2, and includes a mask holding device 82, a mask moving device 83, a clamp mechanism 84, and the like. The mask holding device 82 holds the mask S in a flat state in a pulled state, and includes a mesh 86 and a rectangular mask frame 87. The mask S is a thin film made of metal, and has a plurality of through holes H formed in a plurality of portions corresponding to a plurality of patterns C of the substrate P, as shown in FIGS. 8 and 10. In addition, although patterns C1, C2, C3 and through holes H1, H2, H3 are shown in FIGS. 8 and 10, when it is not necessary to distinguish them, or when they are collectively referred to, the pattern is used. C, sometimes referred to as through hole H. Further, the through holes H and the pattern C shown in FIGS. 8 and 10 and the like are different from the shapes actually formed on the mask S and the substrate P. Further, a pair of reference marks Ms are formed on the diagonally separated portions of the mask S. The pair of reference marks Ms are located on the portion of the mask S corresponding to the pair of reference marks Mp formed diagonally spaced apart from the substrate P.

The mask moving device 83 moves the mask S by moving the mask frame 87 in the xy plane, and as shown in FIG. 5, x provided on the frame cradle 90 for holding the mask frame 87. The mobile device 92, two y mobile devices 94, 95 and the like are included. Since the x-moving device 92 and the y-moving devices 94 and 95 have the same structure, the x-moving device 92 will be described as a representative. The x-moving device 92 includes a driving device 102 and a pressing device 103 provided in portions of the mask frame 87 facing each other in the x-direction. The drive device 102 includes an electric motor 100 and a motion conversion mechanism 101 that converts the rotation of the electric motor 100 into linear movement and transmits it to the mask frame 87. The pressing device 103 is composed of an air cylinder or the like, and applies a reaction force while allowing the mask frame 87 to move by the driving device 102. The driving device 102 and the pressing device 103 are respectively engaged with the mask frame 87 via the roller 104, and the mask frame 87 is held by the frame receiving portion 90 via the rotating body 105. As a result, the mask frame 87 can be smoothly moved in the xy plane. The mask frame 87 is rotated about the z-axis by operating the y moving devices 94 and 95 in different states and operating the x moving device 92.

The clamp mechanism 84 includes four clamp devices 108 provided apart from each other. The clamp device 108 includes a cylinder and a clamp member 106 integrally movably engaged with the piston rod of the cylinder, and a clamp position where the clamp member 106 presses the mask frame 87 by the operation of the cylinder. It is moved to a non-clamping position away from the mask frame 87. At the non-clamping position of the clamp member 106, the mask frame 87 is moved in the xy plane with respect to the frame cradle 90 by the operation of the x moving device 92 and the y moving device 94, 95, and at the clamp position of the clamping member 106. The mask frame 87 is held.

As shown in FIGS. 1 and 2, the squeegee device 12 includes a squeegee head 112 having a pair of squeegees 110a and 110b, and a squeegee moving device 114 for moving the squeegee head 112 in the y direction. The squeegee moving device 114 includes an electric motor 115, a slider (not shown), a screw mechanism 116 as a motion conversion mechanism that converts the rotation of the electric motor 115 into linear movement and transmits it to the slider, a guide rail 117 extending in the y direction, and the like. , The squeegee head 112 is fixedly held by the slider. The head body 119 of the squeegee head 112 is provided with elevating devices 118a, 118b and the like for raising and lowering the squeegees 110a and 110b, respectively.

The first imaging device 14 images the mask S from above, and is movable above the mask S along the mask S. The first image pickup device moving device for moving the first image pickup device 14 includes the x moving device 120 provided in the head main body 119. The x-moving device 120 includes a guide rail 124 extending in the x-direction, an electric motor 125, a ball screw 126 rotated by the electric motor 125, a slider 127 having a nut member engaged with the ball screw 126, and the like. The first imaging device 14 is integrally movably held by the slider 127. The first imaging device 14 is moved in the x direction by the x moving device 120, and is moved in the y direction by the squeegee moving device 114. From this, it can be considered that the first imaging device moving device is composed of the x moving device 120, the squeegee moving device 114, and the like.

The second imaging device 16 images the reference marks Mp and Ms provided on the substrate P and the mask S, and the second imaging device moving device 130 between the substrate holding device 22 and the mask holding device 10. It is possible to enter. As shown in FIG. 6, the second imaging device moving device 130 includes an x moving device 142 and a y moving device 144. The x-moving device 142 includes an electric motor 150, a motion conversion mechanism 154 that converts the rotation of the electric motor 150 into a linear motion of the x slider 152, guide rails 156a and 156b extending in the x-direction, and the like. The y-direction moving device 144 is provided on the x-slider 152, and includes an electric motor 158, a y-slider 161, a motion conversion mechanism 160 that converts the rotation of the electric motor 158 into linear movement of the slider 161, a guide rail 162 extending in the y-direction, and the like. including. The second imaging device 16 is integrally movably held by the y slider 161 and is made movable in the xy plane by the x moving device 142 and the y moving device 144.

The mask printing machine is controlled by the control device 200 shown in FIG. 7. The control device 200 is mainly a computer, and includes an execution unit 204, a storage unit 206, an input / output unit 208, and the like. The first imaging device 14, the second imaging device 16, the display 210, and the like are connected to the input / output unit 208, and the substrate transfer device 4, the substrate lifting device 6, the substrate moving device 8, the mask device 10, and the squeegee device are connected. 12. The x-moving device 120 of the first imaging device moving device, the second imaging device moving device 130, and the like are connected via the drive circuit 212. The display 210 shows the status of the mask printing machine.

The storage unit 206 has shape information which is information about each shape of the plurality of through holes H formed in the mask S and reference position information which is information about a reference position which is a position of each reference point of the plurality of through holes H. A through-hole information storage unit 220 that stores through-hole information including and, and a pattern information storage unit 222 that stores pattern information including shape information and reference position information for each of a plurality of patterns C formed on the circuit board P. Etc. are included. As shown in FIG. 17, the shape information includes information representing the outer shape of each of the through hole H and the pattern C (for example, a circle, a rectangle, a polygon, etc.), and dimensions (for example, a diameter and a side). Information representing (corresponding to length, etc.), information representing a template (for example, information defining an outer shape or an outer line), and the like are included. The reference position information includes information indicating the position of each reference point (for example, a predetermined point such as a center point) of the through hole H and the pattern C. The position is, for example, a position on the xy coordinate when the origin is a predetermined point (for example, an angle, the center point of the origin mark, etc.) corresponding to each other of the mask S and the circuit board P. Can be represented by. In addition, the reference positions are often the same in the through holes H and the pattern C that correspond to each other.

It is not essential that the pattern information storage unit 222 stores information about all of the plurality of patterns C formed on the substrate P. For example, at least one of the plurality of patterns C, which is important, is stored. Information about one pattern C may be stored. The important patterns include, for example, those that require high printing accuracy and those that are small. The same applies to the through hole information storage unit 220.

In the mask printing machine configured as described above, the alignment is performed by adjusting the relative positions of the substrate P and the mask S in the horizontal direction, and then the upper surface of the substrate P comes into contact with the lower surface of the mask S. By raising the squeegees 110a and 110b to the tangent positions and moving the squeegees 110a and 110b, the cream-like solder is applied to the pattern C of the substrate P through the through holes H of the mask S, and mask printing is performed.
The alignment in this case is usually performed based on the reference mark. Specifically, when the substrate P is transported to a predetermined position below the mask S by the substrate transport device 4, the reference mark formed on each of the substrate P and the mask S by the second imaging device 16 Mp and Ms are imaged. Then, the substrate P and the mask S are in the horizontal direction by at least one of the substrate moving device 8 and the mask moving device 83 so that the center points of the pair of reference marks Mp and the center points of the pair of reference marks Ms coincide with each other. The relative position of is corrected, and the alignment is performed. This alignment is referred to as reference mark-based alignment, and the correction value of the horizontal relative position between the substrate P and the mask S in this case is referred to as the reference mark-based correction value.

However, the substrate P and the mask S may not be provided with the reference mark, and in that case, the mark-based alignment cannot be performed. Further, when the substrate P is distorted or deformed, the through hole H and the pattern C may be displaced even if the centers of the substrate marks Mp and Ms are aligned in the horizontal direction. is there.

Therefore, in this embodiment, the mask S is imaged by the first imaging device 14 from above with the mask S and the substrate P overlapping each other, and based on the captured image, at least one through hole H corresponding to each other is taken. Each of the above and each of the at least one pattern C in the horizontal direction (hereinafter, may be simply referred to as a deviation) is individually acquired. Then, by statistically processing the individual deviations, which are the horizontal deviations between each of the individually acquired through holes H and each of the patterns C, the average deviation value, which is the average value of the deviations, is acquired. Will be done. Further, based on the acquired average deviation value, a deviation-based correction value which is a correction value of the horizontal relative position between the mask S and the substrate P is acquired. The deviation dependence correction value can be acquired so that the average deviation value becomes 0, or can be acquired so that the average deviation value becomes the minimum.
After that, the relative positions of the mask S and the substrate P in the horizontal direction are corrected based on the deviation-based correction value, and the deviation-based positioning is performed.

In this case, in the captured image, it is not indispensable to acquire individual deviations for each of the plurality of through holes H corresponding to each other and each of the plurality of patterns C, and at least which is important among the plurality of patterns C. The deviation between each of the one pattern C and each of the corresponding at least one through hole H can be acquired so that the average deviation value can be acquired.

Further, in the deviation, at least the distance Δx, Δy in the horizontal direction (x direction, y direction) between the reference point of the through hole H and the reference point of the pattern C and the angle Δθ formed by the through hole H and the pattern C are at least. One is included.
The horizontal distance between the reference point of the through hole H and the reference point of the pattern C can be obtained as the difference between the reference position, which is the position of the reference point of the through hole H, and the reference position of the pattern C. It can be acquired as the difference in the amount of movement of each template from the pattern C.
Further, the angle formed by the through hole H and the pattern C can be obtained as the angle formed by the reference line set in each of the through hole H and the pattern C, or the rotation angle of each template of the through hole H and the pattern C. It can be obtained as a difference between. Hereinafter, the acquisition of individual deviation and deviation dependence correction values will be specifically described.

Through-hole information and pattern information are input in advance and stored in the through-hole information storage unit 220 and the pattern information storage unit 222. Then, after the reference mark-based alignment is performed or without the reference mark-based alignment, the substrate P is brought into contact with the lower surface of the mask S by raising the substrate P. The state in which the substrate P is in contact with the lower surface of the mask S is one aspect in which the mask S and the substrate P are overlapped with each other. In this state, the first imaging device 14 images the mask S from above.

When the horizontal deviation between the through hole H and the pattern C is small, for example, when the reference mark-based alignment is performed and the distortion of the substrate P is small, the mask S is as shown in FIGS. The through hole H and the pattern C of the substrate P are located at substantially the same positions in the vertical direction. The reference points (Ha1, Ca1) and (Ha2, Ca2) are substantially the same in the through holes H1 and the pattern C1 and the through holes H2 and the pattern C2 corresponding to each other, respectively. Therefore, the outline of the pattern C is usually not visible through the through hole H, and the image representing the outline of the pattern C cannot be recognized in the captured image G shown in FIG. Therefore, it is difficult to acquire the reference position and orientation of the pattern C based on the captured image G.

On the other hand, when the deviation between the through hole H and the pattern C is large, for example, when the reference mark-based alignment is not performed, or when the substrate P is distorted or deformed, the through hole H1 , Lg2 may be visible as part of the outline of patterns C1 and C2 through H2. As shown in FIG. 11, in the captured image G, an image showing a part of the outlines of the patterns C1 and C2 Lg1 and Lg2 may be recognized inside the through holes H1 and H2.

Therefore, in this embodiment, image recognition is performed based on the captured image G by using an image recognition technique such as template matching. As shown in FIG. 12A, the patterns C1 and Lg2 defined in the outlines Lg1 and Lg2 of the patterns C1 and C2 inside the through holes H1 and H2 in the captured image G based on the shape information included in the pattern information. Templates TC1 and TC2 are moved so that a part of the outlines of the entire C2 (for example, templates TC1 and TC2 can be used) L1 and L2 match. Then, as shown in FIG. 12B, the reference position (the position of the reference points Ca1 and Ca2 of the patterns C1 and C2) is based on the movement amount and the rotation angle of the templates TC1 and TC2 in the x-direction and the y-direction. Coordinates) and orientation are estimated.

The positions of the reference points Ca1 and Ca2 of the patterns C1 and C2 can be estimated based on the positions of the reference points C01 and C02 of the templates TC1 and TC2 and the movement amount of the templates TC1 and TC2. The orientation of the pattern C1 can be represented by the tilt angle θC1 of the reference line kC1 of the pattern C1 with respect to the reference axis which is the X-axis or the Y-axis, but the tilt angle θC1 representing the orientation of the pattern C1 is used as the rotation angle of the template TC1. Can be estimated.
The tilt angle θ is a value having a sign (+, −), and the sign indicates the direction of rotation. Further, the inclination angle θ is not acquired when the shape of the pattern C is circular or the like.

The position of the reference point of the patterns C1 and C2 defines the outer shape of the entire pattern C in the captured image G by using the outer lines of the patterns C1 and C2 defined based on the shape information, and the defined pattern. It can be obtained based on the overall outer shape of C. As described above, the reference positions and orientations of the patterns C1 and C2 can be acquired based on the captured image G and the shape information of the pattern, or based on the captured image G and the shape information and the reference position information of the pattern. it can.

On the other hand, the image representing the through hole H is included in the captured image G. Therefore, the reference position and orientation of the through hole H can be acquired at least based on the captured image G. For example, as shown in FIG. 13A, using the reference position information included in the through-hole information, the template TH1, the template so that the outline of the through-hole H on the captured image G and the template TH1 match. TH1 can be moved, and the reference position and the direction θH1 which are the positions of the reference point Ha1 of the through hole H can be obtained based on the movement amount and the rotation angle in the x-direction and the y-direction.
Further, based on the outer shape of the through hole H defined in the captured image G, the reference point Ha1 of the through hole H is acquired to acquire the reference position, and the reference line kH1 of the through hole H is acquired. It is also possible to acquire the inclination angle θH1 with respect to the reference axis of the reference line kH1. Further, when the distortion of the mask S is small, the reference position represented by the reference position information included in the through hole information can be set as the reference position of the through hole H.

Then, as shown in FIG. 13B, when the shape of the through hole H and the pattern C is circular, the x direction between the position of the reference point Ha2 of the through hole H2 and the position of the reference point Ca2 of the pattern C2. When the distances Δx2 and Δy2 in the y direction are acquired and the shape of the through hole H and the pattern C is rectangular, the x direction between the position Ha1 of the reference point of the through hole H1 and the position of the reference point Ca1 of the pattern C1. , The distances Δx1 and Δy1 in the y direction are acquired, and the angle (difference in the rotation angle of the template) Δθ1 formed by the through hole H and the pattern C is acquired.

An example of acquiring a deviation-based correction vector, which is a vector whose components are deviation-based correction values (distance in the x-direction and y-direction, and an angle), will be described based on the deviation-based correction vector acquisition program represented by the flowchart of FIG. To do. In this embodiment, each of the plurality of through holes H corresponding to each other and each of the plurality of patterns C, each of at least one through hole H including an important one, and at least one pattern C corresponding thereto. The deviation from each is acquired. Hereinafter, the target through hole H and the pattern C from which these deviations are acquired will be referred to as the target through hole H and the target pattern C.

In step 1 (hereinafter abbreviated as S1; the same applies to other steps), the reference mark Mp of the substrate P and the reference mark Ms of the mask S are imaged by the second imaging device 16, for example, the reference mark Mp. The relative position of the mask S and the substrate P in the horizontal direction is controlled so that the center point of the reference mark Ms coincides with the center point of the reference mark Ms, and the reference mark-based alignment is performed. Then, the substrate P is raised until it comes into contact with the lower surface of the mask S. In S2, in this state, the first imaging device 14 performs imaging from above to obtain an captured image G, and in S3, n is set to 1. n is a preset number for each of the target through hole H and the target pattern C.

In S4, based on the captured image G and the through-hole information stored in the through-hole information storage unit 220, the position of the reference point Ha1 (xHa1, yHa1) of the target through-hole H of the first mask S, the template TH1 The rotation angle θH1 is acquired.
In S5, the position (xCa1, yCa1) of the reference point Ca1 of the target pattern C1 and the rotation angle θC1 are estimated based on the captured image G and the pattern information stored in the pattern information storage unit 222.
In S6, the distances Δx1, Δy1 between the reference positions xHa1 and yHa1 of the target through hole H1 and the reference positions xCa1 and yCa1 of the target pattern C, and the angle Δθ1 formed by the target through hole H1 and the target pattern C1 are acquired, and individual deviations are obtained. The vector is stored.

As shown in the flowchart of FIG. 15, in S61, the difference in the reference position (value represented by the coordinates) is obtained between the i-th target through hole Hi and the target pattern Ci (Δxi = xCai-xHai, Δyi = yCai). −YHai), the difference between the rotation angles θHi and θCi is obtained as the angle (Δθi = θCi−θHi) formed by the target through hole H and the target pattern C. Then, in S62, the individual deviation vector αi having these individual deviations Δxi, Δyi, and Δθi as components is acquired and stored.

Then, in S7, n is incremented by 1, and in S8, it is determined whether or not n is smaller than the number N of the target through holes and the like. When S8 is executed for the first time, the determination is YES, so the process is returned to S4, and similarly, individual deviation vectors are acquired for the second target through hole and the target pattern.

Hereinafter, individual deviations, individual deviation vectors, etc. between each of the target through holes and each of the target patterns are acquired by executing S4 to 6, respectively, and when n reaches N, the determination of S8 is made. Becomes NO, and in S9, the average deviation value is acquired based on the individual deviation, and the average deviation value vector is acquired. In S10, the deviation dependence correction value is acquired based on the average deviation value which is a component of the average deviation value vector, and the deviation dependence correction vector having the deviation dependence correction value as a component is acquired.
As shown in the flowchart of FIG. 16, in S91, the sum of the values obtained by multiplying the individual deviation components (Δxi, Δyi, Δθi) of each of the target through holes H and each of the target patterns C by the load Wi is loaded. The value divided by the sum of Wi is acquired as the average deviation value, and in S92, the average deviation vector β having the average deviation value as a component is acquired. Further, in this embodiment, the average deviation value is used as the deviation dependence correction value. By moving the mask S or the substrate P by the deviation-based correction value, the deviation between the through hole H and the pattern C can be reduced. The load Wi is a value larger than 0 and smaller than 1, and when the load Wi is large, the influence of the “individual deviation” on the “deviation dependence correction value” becomes large.

In this embodiment, mask printing is performed after the deviation reliance correction vector is acquired.
The substrate P is lowered and separated from the mask S. Then, the mask S or the substrate P is moved in the horizontal direction based on the deviation dependence correction value, so that the relative positions of the substrate P and the mask S in the horizontal direction are corrected. The substrate P is raised and comes into contact with the lower surface of the mask S. In that state, the creamy solder is printed by the squeegees 110a and 110b.
As described above, in this embodiment, the deviation dependence correction value is acquired based on the deviation between each of at least one target through hole H of the mask S and each of at least one pattern C of the substrate P, and the deviation dependence is obtained. Since the horizontal relative positions of the mask S and the substrate P are corrected based on the correction values, the creamy solder can be printed on the pattern with high accuracy even if the reference mark-based alignment is not performed. it can.

Further, the reference position and orientation of at least one target pattern C formed on the substrate P are acquired, and based on this, the deviation from the target through hole H formed in the mask S is acquired, and the deviation dependence correction value is acquired. Therefore, even if the substrate P is distorted or deformed, the creamy solder can be printed on the pattern with high accuracy.
Further, since the reference position and orientation of the target through hole H are acquired based on the captured image G and the deviation from the target pattern C is acquired, even if the mask S is distorted or deformed, the cream is creamed. The state solder can be printed on the pattern with high accuracy.
Further, based on the reference position information of the through hole, it is convenient to specify the position of the target through hole H in the captured image G.

The deviation dependence correction value can be acquired for each substrate P, but when mask printing is continuously performed, it is acquired at the time of the first mask printing and from the second time. Can be aligned using the deviation-based correction value acquired the first time.
Further, in the above embodiment, the image of the mask S is performed by the first imaging device 14 with the substrate P in contact with the lower surface of the mask S, but the substrate P is separated from the lower surface of the mask S. , Imaging can also be performed. This is because even if the substrate P is separated from the lower surface of the mask S, the relative positions of the substrate P and the mask S in the horizontal direction are the same. This state is also assumed to be a state in which the substrate P and the mask S overlap.

Furthermore, when acquiring the average deviation value, it is not essential to apply a load to the individual deviations, and it is possible to acquire the average value of the deviations, which is the value obtained by dividing the total of the individual deviations by the number, as the average deviation value. it can.
Further, when acquiring the horizontal deviation between the target through hole H and the target pattern C, it is not indispensable to acquire the reference positions of the target through hole H and the target pattern C, respectively. For example, the difference in the amount of movement of the respective templates THi and TCi can be acquired as a horizontal deviation between the target through hole H and the target pattern C. In this case, it can be considered that the acquisition of the movement amounts of the templates TCi and TCi corresponds to the acquisition of the reference position of the through hole and the acquisition of the reference position of the pattern, respectively.

As described above, the deviation acquisition device is configured by the portion that stores S1 to S9 of the deviation dependence correction value acquisition program represented by the flowchart of FIG. 14 of the control device 200, the portion that executes the program, and the like, and S10 of the control device 200. The deviation dependence correction value acquisition unit is configured by the part to be stored, the part to be executed, and the like. Of the deviation acquisition device, the portion that acquires the distance between the x-direction and the y-direction of the reference position corresponds to the first deviation acquisition unit, the portion that acquires the inclination angle corresponds to the second deviation acquisition unit, and S5. The reference position estimation part is composed of the part for estimating the reference position among the parts to be stored and the part to be executed, the inclination angle estimation part is composed of the part for estimating the inclination angle, and the part for storing S4 and executing. The through-hole reference position acquisition portion is configured by the portion of the portion that acquires the reference position. Further, the average deviation value acquisition unit is composed of a portion for storing S9 (S91), a portion for executing S9, and the like. Furthermore, the statistically processed value of the individual deviation corresponds to the average deviation value.
Further, S2 corresponds to the imaging process, and S2 to 6 correspond to the deviation acquisition process. It can be considered that the deviation dependence correction value acquisition device is composed of a portion for storing S1 to 10 of the deviation dependence correction value acquisition program represented by the flowchart of FIG. 14 of the control device 200, a portion for executing the program, and the like.

8: Substrate moving device 12: Squeegee device 14: First imaging device 22: Board holding device 82: Mask holding device 83: Mask moving device 110a, 110b: Squeegee 114: Squeegee moving device 120: x moving device

Claims (7)

A mask printing machine that prints viscous fluid on a portion represented by a plurality of patterns formed on a circuit board through a plurality of through holes formed in the mask.
A mask holding device for holding the mask and
A circuit board holding device provided below the mask holding device and holding the circuit board,
An imaging device capable of imaging the mask held by the mask holding device from above,
A pattern information storage unit that stores information about each of the plurality of patterns,
In a state where the circuit board held by the circuit board holding device and the mask held by the mask holding device overlap, the captured image captured by the imaging device and at least stored in the pattern information storage unit. Based on the information regarding the shape of each of the target patterns, which is at least one of the plurality of patterns, the mask is formed on the corresponding mask of each of the at least one target patterns. The relative position of each of the target through holes, which is at least one of the plurality of through holes, is estimated, and the horizontal direction of each of the at least one target through holes and each of the at least one target patterns. A mask printing machine including a deviation acquisition device for acquiring each deviation. The deviation acquisition device
A reference position, which is the position of each reference point of the at least one target pattern, based on the captured image and at least the information about the shape of each of the at least one target patterns stored in the pattern information storage unit. The reference position estimation unit that estimates
The at least one is based on the reference position of each of the at least one target patterns estimated by the reference position estimation unit and the reference position which is the position of each reference point of the at least one target through hole. The mask printing machine according to claim 1, further comprising a first deviation acquisition unit that acquires the distance between each of the reference points of the target through hole and each of the reference points of the at least one target pattern as the deviation. The mask printing machine includes a through-hole information storage unit that stores information about each of the plurality of through-holes.
The first deviation acquisition unit provides information on the shape of each of the captured image and at least one target through hole among the plurality of through holes in the information stored in the through hole information storage unit. The mask printing machine according to claim 2, further comprising a through-hole reference position acquisition unit that acquires the reference position of each of the at least one target through-holes based on the above. The deviation acquisition device
Tilt angle estimation that estimates the tilt angle of each of the at least one target pattern with respect to the reference axis based on the captured image and at least information about the shape of the at least one target pattern stored in the pattern information storage unit. Department and
Each of the target through holes is based on the tilt angle of each of the at least one target patterns estimated by the tilt angle estimation unit and the tilt angle of each of the at least one target through holes with respect to the reference axis. The mask printing machine according to any one of claims 1 to 3, further comprising a second deviation acquisition unit that acquires an angle formed by each of the target patterns as the deviation. The mask and the circuit are based on a value obtained by the mask printing machine statistically processing at least one individual deviation which is a deviation between each of the at least one target through hole and each of the at least one target pattern. The mask printing machine according to any one of claims 1 to 4, which includes a deviation-based correction value acquisition unit that acquires a deviation-based correction value that is a correction value of a position relative to the substrate in the horizontal direction. The deviation reliance correction value acquisition unit divides the total of the values obtained by applying a load to each of the at least one individual deviation by the total of the loads as the statistically processed value. The mask printing machine according to claim 5, wherein a correction value is acquired. Each of the target through holes, which is at least one through hole of the plurality of through holes formed in the mask, and each of the target patterns, which is at least one pattern of the plurality of patterns formed on the circuit board. This is a deviation acquisition method for acquiring the deviation in the horizontal direction.
An imaging step of imaging the mask from above with the mask and the circuit board overlapped with each other.
A relative position estimation step of estimating the relative position of the target pattern with respect to the target through hole, which is the corresponding through hole, based on the captured image obtained in the imaging step and the information about the target pattern.
The individual deviation acquisition step of individually acquiring the deviation between each of the at least one target through hole and each of the at least one target pattern based on the relative position estimated in the relative position estimation step is included. How to get the deviation.

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