WO2019058926A1

WO2019058926A1 - Method for displaying printing result and screen printing method

Info

Publication number: WO2019058926A1
Application number: PCT/JP2018/032303
Authority: WO
Inventors: 礒端　美伯; 聖弥黒田; 奨豊田
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2017-09-25
Filing date: 2018-08-31
Publication date: 2019-03-28
Also published as: DE112018004326T5; CN111093997B; JP7113183B2; CN111093997A; JPWO2019058926A1

Abstract

Provided is a method for displaying a printing result in a screen printing apparatus that is provided with a mask having a pattern hole and a squeegee moving on the mask, wherein the pattern hole is filled with a paste on the mask by moving the squeegee on the basis of a preset printing condition, and the paste with which the pattern hole is filled is transferred onto a substrate. The squeegee is moved with respect to the mask on the basis of the preset printing condition, whereby an examination hole provided in the mask separately from the pattern hole is filled with the paste. A change in pressure of the paste with which the examination hole is filled is acquired as a pressure waveform, and a filling pressure and a filling time are detected from the pressure waveform. Then, the detected filling pressure and the filling time are displayed on a display monitor together with a preset determination criterion.

Description

Display method of printing result and screen printing method

The present invention relates to a method of displaying printing results and a screen printing method in a screen printing apparatus that moves a squeegee on a mask close to a substrate to print paste on the substrate.

The screen printing apparatus includes a mask having a pattern hole and being in proximity to the substrate, and a squeegee moving on the mask in proximity to the substrate, and the pattern hole of the mask is moved by moving the squeegee on the mask. Is filled with paste so that the paste is printed on the substrate. In such a screen printing apparatus, it is important to properly set various printing conditions that affect the quality of printing. Patent Document 1 below describes a screen printing apparatus provided with a pressure sensor for detecting the pressure of cream solder to be printed through an opening for pressure detection formed in a mask. In this screen printing apparatus, the waveform detection result of the pressure detected by the pressure sensor is compared with the optimum waveform registered in the database, and the change of the printing condition and the measurement of the filling pressure are repeated until the two coincide.

JP 2001-71455 A

However, it has been difficult to accurately determine whether the printing conditions are appropriate only by comparing the pressure waveform detection result detected by the pressure sensor with the optimum waveform. In addition, as described above, even if the actual value of the pressure can be obtained, it is the operator who decides which one of the plurality of printing conditions should be changed in order to obtain a good printing result. In the face of relying on the experience of the above, there was a problem that an unskilled worker of the experience had to set printing conditions to some extent by trial and error.

Therefore, the present invention has an object of providing a display method and a screen printing method of a printing result in a screen printing apparatus which can easily determine the suitability of printing conditions or can automatically set the printing conditions. I assume.

The display method of the printing result of the present invention includes a mask having a pattern hole and a squeegee moving on the mask, and moves the squeegee based on a preset printing condition to make the paste on the mask a pattern hole It is a display method of the printing result in the screen printing apparatus which transcribe | transfers the paste with which it filled and was filled in the pattern hole to a board | substrate, Comprising: The pattern hole is made to move with respect to a mask based on the printing conditions set beforehand. The inspection hole provided in the mask separately is filled with paste, the change in pressure of the paste filled in the inspection hole is acquired as a pressure waveform, the filling pressure and filling time are detected from the pressure waveform, and the detected filling The pressure and the filling time are displayed on the display monitor together with the judgment criteria set in advance.

The screen printing method of the present invention comprises a mask having a pattern hole and a squeegee moving on the mask, and the paste on the mask is filled into the pattern hole by moving the squeegee based on a preset printing condition. And a screen printing method in a screen printing apparatus for transferring the paste filled in the pattern holes to a substrate, wherein the pattern holes are obtained by moving the squeegee with respect to the mask based on preset temporary printing conditions. Separately fill the inspection holes provided in the mask with paste, acquire the change in pressure of the paste filled in the inspection holes as a pressure waveform, detect the filling pressure and filling time from the pressure waveform, and fill pressure and filling time It is determined whether or not the preset determination criteria are satisfied, and when the determination criteria are satisfied, the temporary printing conditions are set as the printing conditions for production If the determination criteria are not satisfied, the temporary printing conditions are changed, and based on the changed temporary printing conditions, the process from the filling of the paste into the inspection hole to the determination as to whether the determination criteria are satisfied is performed again. The paste on the mask is filled in the pattern holes by moving the squeegee based on the printing conditions, and the paste filled in the pattern holes is transferred to the substrate.

According to the present invention, it is possible to easily determine whether the printing conditions are appropriate. Further, according to the present invention, printing conditions can be set automatically.

FIG. 1 is a plan view of a screen printing apparatus according to a first embodiment of the present invention. FIG. 2 is a front view of the screen printing apparatus according to the first embodiment of the present invention. FIG. 3 is a side view of the screen printing apparatus in the first embodiment of the present invention. FIG. 4 is a plan view of a mask provided in the screen printing apparatus according to the first embodiment of the present invention. FIG. 5 is a block diagram showing a control system of the screen printing apparatus in the first embodiment of the present invention. FIG. 6 is a side view showing a mask provided in the screen printing apparatus according to the first embodiment of the present invention together with a substrate. FIG. 7 is a plan view of a mask provided in the screen printing apparatus according to the first embodiment of the present invention. FIG. 8 is a view showing the screen printing apparatus in the first embodiment of the present invention filling the substrate with the paste through the mask. FIG. 9 is a view showing the screen printing apparatus in the first embodiment of the present invention filling the inspection holes of the mask with paste. FIG. 10A is a view showing a state in which cleaning is performed by the cleaning unit provided in the screen printing apparatus according to the first embodiment of the present invention. FIG. 10B is a view showing a state in which cleaning is performed by the cleaning unit provided in the screen printing apparatus according to the first embodiment of the present invention. FIG. 10C is a diagram showing a state in which cleaning is performed by the cleaning unit provided in the screen printing apparatus according to the first embodiment of the present invention. FIG. 11 is a graph showing temporal changes in filling pressure measured by the screen printing apparatus in the first embodiment of the present invention. FIG. 12 is a graph showing an example of determination criteria set by the screen printing apparatus according to the first embodiment of the present invention. FIG. 13A is a view showing the printing pressure and the filling time obtained by measuring the temporal change of the filling pressure by the screen printing apparatus according to the first embodiment of the present invention, together with the set judgment criteria graph. FIG. 13B is a view showing the printing pressure and the filling time obtained by measuring the temporal change of the filling pressure by the screen printing apparatus according to the first embodiment of the present invention, together with the set determination reference graph. FIG. 14 is a block diagram showing a control system of the screen printing apparatus in the second embodiment of the present invention. FIG. 15 is a flow chart showing the setting procedure of the printing conditions performed by the screen printing apparatus in the second embodiment of the present invention. FIG. 16 is a view showing how the screen printing apparatus in the modified example of the first and second embodiments of the present invention fills the paste in the inspection hole of the mask.

First Embodiment
FIGS. 1, 2 and 3 show a screen printing apparatus 1 according to a first embodiment of the present invention. FIG. 1 is a plan view of the screen printing apparatus 1. FIG. 2 is a front view of the screen printing apparatus 1. FIG. 3 is a side view of the screen printing apparatus 1. The screen printing apparatus 1 is an apparatus for carrying in the substrate 2 supplied from the upstream process side, printing a paste such as solder on the surface of the substrate 2 and carrying it out to the downstream process side. Here, for convenience of explanation, the left-right direction of the screen printing apparatus 1 viewed from the operator OP is taken as the X-axis direction, the left side is taken as the upstream process side, and the right side is taken as the downstream process side. Further, the front-rear direction of the screen printing apparatus 1 viewed from the operator OP is taken as a Y-axis direction, the front side viewed from the operator OP is referred to as the front, and the back side viewed from the operator OP is referred to as the rear. Furthermore, the vertical direction of the screen printing apparatus 1 is taken as the Z-axis direction.

In FIG. 1, FIG. 2 and FIG. 3, the screen printing apparatus 1 includes a substrate holding unit 21 and a substrate holding unit moving mechanism 22 on a base 11. A mask 13 is provided above the substrate holding unit 21. A carry-in conveyor 14 is provided on the upstream process side of the substrate holding unit 21, and a carry-out conveyor 15 is provided on the downstream process side of the substrate holding unit 21 (FIG. 1). The print head 16 is provided above the mask 13, and the imaging unit 17 and the cleaning unit 18 are provided in the region between the mask 13 and the substrate holding unit 21 (FIGS. 2 and 3).

In FIG. 1, the substrate holding unit 21 includes a pair of clamp members 21A that can be opened and closed in the Y-axis direction. The pair of clamp members 21A clamps and holds both side portions of the substrate 2 carried in from the upstream process side facing in the Y-axis direction. In FIG. 2, the substrate holding unit 21 includes a lift table 21 a and a substrate support unit 21 b that supports the substrate 2 from below. The substrate holding portion moving mechanism 22 is provided on an XY table 22A that moves in a horizontal plane with respect to the base 11, a θ table 22B that rotates around the Z axis provided on the XY table 22A, and a θ table 22B. A substrate lifting mechanism 22C for lifting and lowering the unit 21 is provided. These are stacked in order from the bottom, and the uppermost substrate lifting mechanism 22C is coupled to the lifting table 21a. Therefore, the substrate 2 held by the substrate holding unit 21 is moved in the horizontal plane in the horizontal direction by the XY table 22A and the θ table 22B and rotated about the Z axis, and the substrate lifting mechanism 22C moves the substrate 2 against the mask 13. It can be approached and separated.

In FIG. 1, FIG. 2 and FIG. 3, the mask 13 is made of a metal plate-like member and is disposed in a horizontal posture. A pattern formation region 13R is set at the central portion of the mask 13. A large number of pattern holes 13H corresponding to the electrodes provided on the upper surface of the substrate 2 are provided in the pattern formation region 13R (FIG. 4).

In FIG. 1, FIG. 2 and FIG. 3, the print head 16 is provided with a print head moving table 31, two squeegee elevators 32 and two squeegees 33. The print head moving table 31 extends in the X-axis direction in the upper region of the mask 13, and the print head moving unit 16K (FIG. 5) moves the print head moving table 31 (that is, the print head 16) in the Y axis direction.

The two squeegee elevators 32 are provided on the print head moving table 31 side by side in the Y-axis direction, and the rods 32R directed downward respectively protrude below the print head moving table 31. The two squeegees 33 are attached to the lower end of the rod 32R of each of the two squeegee elevators 32, and are arranged below the print head moving table 31 in the Y-axis direction.

2 and 3, each squeegee 33 includes a squeegee base 41, a blade 42, and an attack angle adjusting unit 41M. The squeegee base 41 is attached to the rod 32R of the squeegee lifting unit 32, and the blade 42 is attached to the squeegee base 41 so as to be pivotable about the X axis. The two blades 42 extend in a direction in which opposing surfaces (referred to as paste scraping surfaces 42M) spread downward as viewed from the X-axis direction (FIG. 3). The attack angle adjustment unit 41M has a function of adjusting an angle formed by the paste scraping surface 42M of the blade 42 and the upper surface of the mask 13, that is, the attack angle Φ.

The imaging unit 17 incorporates a camera with the imaging optical axis facing upward and a camera with the imaging optical axis facing downward, and images imaging objects located above and below at the same time or not simultaneously. The imaging unit moving unit 17 K (FIG. 5) moves the imaging unit 17 in the X-axis direction and the Y-axis direction in the lower area of the mask 13.

In FIGS. 2 and 3, the cleaning unit 18 includes a base 51, a mask cleaning unit 52 and a sensor cleaning unit 53. The base body 51 extends in the X-axis direction in the lower region of the mask 13, and the cleaning unit moving unit 18K (FIG. 5) moves the base body 51 (that is, the cleaning unit 18) in the Y-axis direction. The mask cleaning unit 52 is formed of a paper member disposed to protrude above the base body 51. The sensor cleaning unit 53 includes a suction mechanism provided to protrude downward of the base body 51.

The substrate holding unit moving mechanism 22 displaces the substrate holding unit 21 in the horizontal direction so that the positions of the electrode 2D of the substrate 2 held by the substrate holding unit 21 and the pattern holes 13H of the mask 13 coincide with each other. The substrate 2 is raised by contact with the lower surface of the mask 13 and positioned (FIG. 6). In a state where the substrate 2 is positioned, the pattern formation region 13R of the mask 13 faces the upper surface of the substrate 2, and the pattern hole 13H of the mask 13 faces the electrode 2D of the substrate 2 vertically (FIG. 6). Note that graphics and characters are printed on the upper surface of the substrate 2 by silk printing 2E, and even when the substrate 2 is brought into contact with the lower surface of the mask 13, there may be a gap GP between the electrode 2D and the mask 13 .

In FIGS. 1 and 4, an inspection hole 13K is provided at a position deviated from the pattern formation region 13R of the mask 13 in the X-axis direction. The inspection holes 13 K penetrate in the thickness direction of the mask 13. As shown in FIG. 2, a sensor mount 21M is provided on the upper surface of the substrate holder 21 at a position opposed to the inspection hole 13K in the state where the substrate 2 is positioned. A pressure detection sensor 60 for detecting the pressure applied to the upper surface is provided on the upper portion of the sensor mount portion 21M (FIGS. 1, 2 and 3).

The sensor mount unit 21M is lifted and lowered by a sensor mount lifting and lowering mechanism 21c disposed on the lifting and lowering table 21a. When loading the substrate 2 from the loading conveyor 14 into the substrate holding unit 21, the sensor mount elevating mechanism 21 c lowers the sensor mount unit 21 M so that the sensor mount unit 21 M and the pressure detection sensor 60 do not interfere with the transfer of the substrate 2. Move to Further, the sensor mount elevating mechanism 21c raises the sensor mount portion 21M so that the pressure received by the pressure detection sensor 60 is positioned immediately below the inspection hole 13K when at least the substrate 2 is positioned on the mask 13.

The squeegee lifting unit 32 lowers the squeegee 33 with the substrate 2 positioned, and brings the blade 42 into contact with the upper surface of the mask 13. In addition, the squeegee lifting unit 32 has a function of adjusting a force (printing pressure) for pressing the squeegee 33 against the upper surface of the mask 13. At this time, the paste scraping surface 42M of each blade 42 abuts on the upper surface of the mask 13 at a predetermined angle (the above-mentioned attack angle。, FIG. 3).

In FIG. 5, the control device 70 included in the screen printing apparatus 1 performs the loading operation of the substrate 2 by the loading conveyor 14, the holding operation of the substrate 2 by the substrate holding unit 21, and the positioning of the substrate 2 with respect to the mask 13 by the substrate holding unit moving mechanism 22. Operation and control of the unloading operation of the substrate 2 by the unloading conveyor 15 are performed. Further, the control device 70 controls the moving operation of the print head 16 by the print head moving unit 16K, the raising and lowering operation of the squeegee 33 by the squeegee lifting unit 32, and the adjustment operation of the attack angle Φ of the blade 42 by the attack angle adjusting unit 41M. Do. The control device 70 controls the moving operation of the imaging unit 17 by the imaging unit moving unit 17K, the imaging operation by the imaging unit 17, the moving operation of the cleaning unit 18 by the cleaning unit moving unit 18K, and the cleaning operation by the cleaning unit 18. Do.

In FIG. 5, the pressure detection sensor 60 is connected to the control device 70, and the pressure detected by the pressure detection sensor 60 is input to the control device 70. The control device 70 is connected to a touch panel 71 as an input / output device. The touch panel 71 functions as an input device for the operator OP to perform required input to the control device 70, and the control device 70 displays the state of the screen printing device 1 to the operator OP or gives an operation instruction to the operator OP. Function as a display monitor.

In FIG. 5, the control device 70 includes a source data storage unit 70a, a printing condition storage unit 70b, and a print control unit 70c. The matrix data storage unit 70a stores information on the substrate 2 to be screen-printed and the mask 13 to be used for the substrate 2 (hereinafter referred to as mask / substrate data). The mask data storage unit 70a stores, as mask / substrate data, data of at least a pattern hole maximum dimension, a pattern hole minimum area, a mask thickness, and a gap GP. These data are stored in the master data storage unit 70a before the screen printing operation.

The largest dimension of the pattern hole stored in the data storage unit 70a is the maximum value among the dimensions (dimension DH shown in FIG. 7) in the moving direction of the squeegee 33 of all the pattern holes 13H included in the mask 13. is there. The pattern hole minimum area is the minimum value among the opening areas SH (areas of the regions shown by oblique lines in FIG. 7) of all the pattern holes 13H included in the mask 13. The mask thickness is the dimension TH in the thickness direction of the mask 13 shown in FIG. The gap GP is, as described above, the vertical distance between the electrode 2D and the mask 13 when the substrate 2 is positioned with respect to the mask 13 (FIG. 6).

The printing condition storage unit 70 b stores printing conditions necessary for the screen printing apparatus 1 to perform the printing operation. The printing conditions stored in the printing condition storage unit 70 b include the printing conditions regarding the squeegee 33, the printing conditions regarding the substrate holding unit moving mechanism 22, and the printing conditions regarding the operation of the cleaning unit 18. The printing conditions for the squeegee 33 include printing pressure, attack angle Φ, and moving speed (squeegee speed).

The printing conditions for the substrate holding unit moving mechanism 22 include information on an operation (a plate separating operation) for separating the substrate 2 from the mask 13, for example, the lowering speed of the substrate 2. The printing conditions for the operation of the cleaning unit 18 include information on the frequency of cleaning of the mask 13. Among these printing conditions, the printing conditions for the squeegee 33 are susceptible to the paste used. For this reason, when the state of the paste changes due to the printing operation of the screen printing apparatus 1 and a printing failure occurs, it is necessary to adjust the printing conditions for the squeegee 33.

The operator can use the touch panel 71 to input setting of printing conditions for the squeegee 33, that is, an input for setting the attack angle と and an input for setting the squeegee speed. When the operator performs an input for setting the attack angle と and the squeegee speed, the input value is stored in the printing condition storage unit 70b.

The print control unit 70 c controls a series of printing operations for printing the paste on the substrate 2 based on the printing conditions stored in the printing condition storage unit 70 b. At this time, the print control unit 70c operates the attack angle adjustment unit 41M such that the attack angle Φ of the squeegee 33 becomes the angle stored in the printing condition storage unit 70b, and the moving speed of the squeegee 33 is stored in the printing condition storage unit 70b. The print head moving unit 16K is operated to achieve the stored speed. The print control unit 70 c operates the substrate holding unit moving mechanism 22 so that the lowering speed of the substrate 2 in the plate separation operation becomes the speed stored in the printing condition storage unit 70 b.

In the printing operation performed by the screen printing apparatus 1, first, the loading conveyor 14 receives the substrate 2 input from the outside and delivers it to the substrate holding unit 21. The substrate holding unit 21 clamps the substrate 2 by the pair of clamp members 21A. Hold. When the substrate holding unit 21 holds the substrate 2, the imaging unit 17 images both the substrate 2 or the substrate 2 and the mask 13. When the control device 70 recognizes the image captured by the imaging unit 17 and determines the positional deviation (relative positional relationship) between the mask 13 and the substrate 2, the substrate holding unit moving mechanism 22 operates based on the result, and the substrate 2 is positioned close to the mask 13 from below and positioned. Specifically, the substrate holding unit moving mechanism 22 moves the substrate holding unit 21 holding the substrate 2 in the horizontal plane by the XY table 22A and rotates the θ table 22B in the horizontal plane. This is performed by raising and lowering by the substrate lifting mechanism 22C.

When the substrate holding unit moving mechanism 22 positions the substrate 2, the squeegee lifting unit 32 lowers the squeegee 33 to bring the blade 42 into contact with the upper surface of the mask 13, and the blade 42 is masked by the printing pressure set in the printing conditions. Press on 13 Then, the print head moving unit 16K moves the print head 16 in the horizontal direction (Y-axis direction) at a moving speed set in the printing conditions, and scrapes the paste Pst with the paste scraping surface 42M of the blade 42. At this time, the squeegee 33 passes (moves) through the pattern formation region 13R of the mask 13 and fills the paste hole P with the paste Pst (FIG. 8). Further, at the time of filling the paste Pst into the pattern hole 13H, the squeegee 33 also fills the paste Pst in the inspection hole 13K located on the passage (FIG. 9).

When the squeegee 33 moves on the mask 13 and the pattern holes 13H are filled with the paste Pst, the substrate holding unit moving mechanism 22 operates to lower the substrate 2 at a descending speed set as the printing condition, and from the mask 13 The substrate 2 is separated (plate separation). Printing of the paste Pst on the substrate 2 is thus completed. When the printing of the paste Pst on the substrate 2 is completed, the substrate holding unit 21 delivers the substrate 2 on which the printing of the paste Pst is completed to the unloading conveyor 15, and the unloading conveyor 15 takes the substrate 2 received from the substrate holding unit 21 to the outside. Take it out.

When the unloading conveyor 15 unloads the substrate 2 out, the cleaning unit moving unit 18K moves the cleaning unit 18 in the Y-axis direction. At this time, the mask cleaning unit 52 is brought into contact with the lower surface of the mask 13 and rubbed against the mask 13 to wipe off the paste Pst attached to the lower surface of the mask 13 and clean it (FIG. 10A → FIG. 10B → FIG. 10C). The cleaning of the mask 13 by the cleaning unit 18 is performed based on the frequency set as the printing condition (performed every time the printing operation is completed, or performed when the printing operation is completed a predetermined number of times).

After the cleaning of the mask 13 is completed, the cleaning unit 18 cleans the pressure detection sensor 60 by the sensor cleaning unit 53. The sensor cleaning unit 53 removes the paste Pst attached to the pressure detection sensor 60 through the inspection hole 13K by the suction operation and the wiping operation (FIG. 10B). When the cleaning of the mask 13 and the pressure detection sensor 60 is completed in this manner, the paste Pst can be printed on the next substrate 2.

In FIG. 5, the control device 70 includes a measurement unit 70 d, a determination reference setting unit 70 e, and a measurement result display unit 70 f. The measurement unit 70d obtains the voltage output from the pressure detection sensor 60 as a pressure waveform, and obtains the filling time and the filling pressure from the pressure waveform.

FIG. 11 shows an example of the pressure waveform acquired by the measuring unit 70d. In the figure, Pt is a threshold value for determining the start and end of the filling of the paste Pst into the inspection hole 13K. The measuring unit 70d determines that the paste Pst is filled in the inspection hole 13K and the pressure exceeds the threshold Pt and that the filling starts and determines that the squeegee 33 passes the inspection hole 13K and the filling is completed when the pressure is less than the threshold Pt. . And measurement part 70d detects time from a filling start to filling completion as filling time. Furthermore, the measuring unit 70d detects the peak value of the pressure as the filling pressure. The filling pressure is susceptible to the printing pressure and the attack angle Φ, and the higher the printing pressure or the smaller the attack angle Φ, the higher the filling pressure. On the other hand, the filling time changes with the squeegee speed, and tends to increase as the squeegee speed decreases.

The determination criterion setting unit 70e sets a determination criterion for determining whether or not the filling pressure and the filling time measured by the measuring unit 70d are within appropriate ranges. If this determination criterion is satisfied, the printing conditions set in the printing condition storage unit 70b are treated as appropriate. In other words, the determination reference setting unit 70e sets the determination reference for determining the suitability of the printing condition by the filling pressure and the filling time. The judgment criteria are shown in FIG.

FIG. 12 shows a two-dimensional graph with the filling pressure on the vertical axis and the filling time on the horizontal axis. The hatched rectangular area indicated by the hatched box surrounded by lower limit value P1 (lower limit pressure), upper limit value P2 (upper limit pressure) and lower limit value T1 (lower limit time) of filling time, upper limit T2 (upper limit time) (Range satisfying the determination criteria) GR.

In screen printing, "bad" and "blur" account for the majority of printing defects. Fading is a defect that a sufficient amount of paste Pst is not printed on the substrate 2, and the main factor is the insufficient filling of the paste Pst into the pattern holes 13H. Underfilling is known to occur easily when the filling pressure is insufficient or the filling time is short. On the other hand, bleeding is a phenomenon in which the paste Pst is printed excessively on the substrate 2 and is generated when the paste Pst protruding from the pattern hole 13H to the back surface of the mask 13 is transferred to the substrate 2. It is known that the protrusion of the paste Pst to the back surface of the mask 13 occurs when the filling pressure is too high or the filling time is too long. Based on such knowledge, the lower limit value P1 and the upper limit value P2 of the filling pressure for determining the acceptance range GR and the lower limit value T1 and the upper limit value T2 of the filling time are set.

The pass range GR changes depending on the size and area of the pattern hole 13H, the thickness of the mask 13 and the gap GP. For example, a small pattern hole 13H requires a filling pressure higher than the filling pressure required for the large pattern hole 13H. In the case of the substrate 2 having a large gap GP, it is necessary to reduce the filling pressure to suppress the occurrence of bleeding. There are innumerable combinations of the dimension and area of the pattern hole 13H, the thickness of the mask 13 and the gap GP included in the mask / substrate data. The determination criteria setting unit 70e according to the present embodiment obtains a print result based on various mask and substrate data obtained in past experiments and screen printing, and a filling pressure indicating a passing range GR according to a learning model in which the print result is machine-learned. The lower limit value P1 and the upper limit value P2 of the above, and the lower limit value T1 and the upper limit value T2 of the filling time are set.

The measurement result display unit 70 f visually displays the filling pressure and the filling time measured by the measuring unit 70 d together with the determination reference displayed by the touch panel 71. As an example of the display, as shown in FIG. 13A and FIG. 13B, the filling pressure obtained on the vertical axis, and the filling time obtained on the two-dimensional graph having the filling time on the horizontal axis. And the filling time (the point Q1 shown in FIG. 13A and the point Q2 shown in FIG. 13B) are displayed.

Next, the procedure for confirming the propriety of the printing conditions regarding the squeegee 33 of the screen printing apparatus 1 configured as described above will be described. As a preparation, the operator OP sets the mask 13 and the substrate 2 used for screen printing in the screen printing apparatus 1. The substrate 2 may use a dummy. Next, the operator OP operates the touch panel 71 to register mask / substrate data and printing conditions (temporary printing conditions) to be checked for suitability in the source data storage unit 70a and the printing condition storage unit 70b. When the mask / substrate data is registered in the data storage unit 70a, the determination criterion setting unit 70e sets the lower limit P1 and the upper limit P2 of the filling pressure indicating the acceptable range GR and the lower limit T1 and the upper limit T2 of the filling time. Set

Next, the operator OP causes the screen printing apparatus 1 to execute screen printing by operating the touch panel 71, and causes the measurement unit 70d to measure the filling pressure and causes the measurement result display unit 70f to display the measurement result.

The operator OP checks the measurement result displayed on the touch panel 71 to determine whether the filling pressure and the filling time are within the acceptance range GR, that is, whether the determination criterion is satisfied. Then, if it is determined that the operator OP satisfies the determination criteria, the operator OP determines that the temporary printing conditions are appropriate, and causes the screen printing apparatus 1 to execute screen printing as the printing conditions for production. On the other hand, if it is determined that the operator OP does not satisfy the determination criterion, the operator OP determines that the temporary printing condition is inappropriate, and operates the touch panel 71 to correct the printing condition. In FIG. 13B, the filling time is shorter than the lower limit value T1. Therefore, the moving speed of the squeegee 33, which is one of the printing conditions, is made slower than the provisional setting. After the operator OP corrects the printing conditions, the operator OP executes the confirmation of the suitability of the printing conditions after the correction according to the above-described procedure, and repeats the process until the printing conditions are determined to be appropriate. As a result, printing conditions for production are set in the printing condition storage unit 70b.

Second Embodiment
The screen printing apparatus 1 in the second embodiment differs from the screen printing apparatus 1 in the first embodiment in that it has a function of automatically correcting and setting printing conditions. Specifically, as shown in FIG. 14, only the printing condition setting unit 70 g of the control device 70 is provided. Next, a method of setting printing conditions will be described according to the flowchart shown in FIG. As in the first embodiment, the mask / substrate data is registered in advance in the matrix data storage unit 70a, and the printing conditions are registered in the printing condition storage unit 70b. The printing conditions at the present time are temporary values, that is, temporary printing conditions.

The operator OP operates the touch panel 71 to cause the control device 70 to start the processing of the flowchart shown in FIG. The print control unit 70c reads the printing conditions stored in the printing condition storage unit 70b (step ST1). Here, if it is necessary to change the attack angle Φ, the attack angle 部 is adjusted by the attack angle adjustment unit 41M.

Next, the print control unit 70c starts a printing operation for printing the paste Pst on the substrate 2 under the printing conditions read in step ST1 (step ST2). During this time, the measurement process of detecting the pressure waveform by the measurement unit 70d is performed (step ST3).

When the printing operation is completed (step ST4), next, the measuring unit 70d obtains the filling pressure and the filling time from the pressure waveform (step ST5). Then, the measurement result display unit 70f displays the measurement result on the touch panel 71 together with the determination criterion (the acceptance range GR) (step ST6).

Next, the printing condition setting unit 70g determines whether the filling pressure and the filling time measured in the measurement process satisfy the determination criteria (step ST7). Specifically, if the filling pressure is within the range between the lower limit value P1 and the upper limit value P2 and the filling time is within the range between the lower limit value T1 and the upper limit value T2, it is judged as pass. Then, the printing condition setting unit 70g sets the printing conditions stored in the printing condition storage unit 70b as temporary printing conditions as printing conditions for production. On the other hand, if it is determined that the printing conditions do not pass, the printing condition setting unit 70g executes a correction process of correcting the printing conditions (step ST8). Then, the process returns to the process of step ST1 again, and the propriety judgment and correction for the corrected printing conditions are performed.

Here, the correction process will be described. The filling time depends on the squeegee speed. Therefore, if the measured filling time falls below the lower limit value T1, correction is performed to slow the squeegee speed. Conversely, if the filling time upper limit value T2 is exceeded, correction is performed to increase the squeegee speed. The filling pressure is susceptible to the printing pressure and the attack angle Φ, and the higher the printing pressure or the smaller the attack angle 高く, the higher. If the measured filling pressure falls below the lower limit value P1, correction is performed to increase the printing pressure or to reduce the attack angle 角. On the contrary, when the filling pressure exceeds the upper limit value P2, a correction to lower the printing pressure or a correction to increase the attack angle Φ is performed. The printing pressure and the correction of the attack angle Φ may be used in combination. As described above, the correction of the printing conditions is automatically performed by the printing condition setting unit 70g, and the printing condition storage unit 70b is overwritten.

In the second embodiment, setting of printing conditions is automatically performed. Usually, the setting of the printing conditions is performed in the preparation stage before starting the substrate production, but may be appropriately performed during the substrate production. Among the pastes Pst, the cream solder has a large change in viscosity and thixo during substrate production, and printing defects may occur due to the change in the cream solder even under the optimum printing conditions set before substrate production. For this reason, during substrate production, it is regularly checked whether the condition where the printing conditions meet the judgment criteria is maintained, and if not maintained, the printing conditions are self-corrected so as to satisfy the judgment criteria. Be done.

In this case, when the squeegee 33 moves on the mask 13 during substrate production (when the pattern holes 13H are filled with the paste Pst), the pressure detection sensor 60 detects the filling pressure via the paste Pst filled in the inspection holes 13K. By doing this, the measurement process of step ST3 is performed. As described above, by setting the printing conditions during substrate production, the printing conditions of the screen printing apparatus 1 always become appropriate values, and the non-defective rate of the substrate 2 to be produced (substrate 2 on which screen printing is performed) is improved. be able to.

As described above, in the display method and the screen printing method of the printing result in the screen printing apparatus 1 described above, the squeegee 33 is moved with respect to the mask 13 under the temporary printing conditions read from the storage unit (the printing condition storage unit 70b) The paste Pst is filled in the inspection holes 13 K provided in the mask 13, and the filling pressure and the filling time are detected from the pressure waveform measured at the time of the filling. Then, it is determined whether or not the detected filling pressure and filling time satisfy the judgment criteria, and if satisfied, temporary printing conditions are set as production printing conditions, and if not satisfied, printing conditions are automatically generated. I am trying to fix it. Then, the correction of the printing conditions is repeated until the filling pressure and the filling time detected under the corrected printing conditions satisfy the judgment criteria. This makes it possible to automatically set the printing conditions regardless of the experience of the worker OP individual.

Although the first and second embodiments of the present invention have been described above, the present invention is not limited to the above. For example, in the above embodiment, the inspection hole 13K is deviated from the pattern formation region 13R of the mask 13 in the X-axis direction, that is, on the passage of the squeegee 33 when the squeegee 33 fills the pattern hole 13H with the paste Pst. Although provided, this is an example and the position of the inspection hole 13K on the mask 13 is not limited. Therefore, for example, it may be provided on the mask 13 opposite to one of the two clamp members 21A clamping the both sides of the substrate 2 located at the printable position. Further, although the shape of the pattern hole 13H is rectangular (square), it may be a circle or the like.

In the first and second embodiments described above, the paste Pst filled in the inspection hole 13K is configured to be in direct contact with the pressure detection sensor 60. However, as shown in the modification of FIG. Attach a (for example, a film-like) closing member 13F made of a material that allows the pressure detection sensor 60 to detect the pressure applied to the paste Pst filled in the inspection hole 13K while closing the lower end side of the inspection hole 13K. It can also be done. In this case, the paste Pst does not adhere to the pressure detection sensor 60, so that the cleaning unit 18 does not have to include the sensor cleaning unit 53.

Abstract: A display method and a screen printing method of a printing result in a screen printing apparatus capable of easily performing setting of printing conditions regardless of experience.

Reference Signs List 1 screen printing apparatus 2 substrate 13 mask 13H pattern hole 13K inspection hole 33 squeegee 70b printing condition storage unit (storage means)
Pst paste

Claims

A mask having a pattern hole, and a squeegee moving on the mask, the paste on the mask is filled into the pattern hole by moving the squeegee based on a preset printing condition, and the pattern hole A method of displaying a printing result in a screen printing apparatus for transferring the paste filled in the above to a substrate,
The paste is filled in the inspection holes provided in the mask separately from the pattern holes by moving the squeegee with respect to the mask based on the printing conditions set in advance.
Change in pressure of the paste filled in the inspection hole is acquired as a pressure waveform,
The filling pressure and filling time are detected from the pressure waveform,
The display method of the printing result displayed on a display monitor with the determination reference | standard which preset the said filling pressure and the said filling time which were detected.
The display method according to claim 1, wherein the filling pressure, the filling time, and the determination reference are displayed on a graph in which the filling time and the filling pressure are on two axes.
The display method according to claim 1, wherein the filling pressure is a maximum value of the pressure in the pressure waveform.
The display method according to claim 1, wherein the filling time is a time when the pressure exceeding a predetermined threshold value is detected in the pressure waveform.
The printing conditions include a printing pressure indicating a force pressing the squeegee against the upper surface of the mask, an attack angle which is an angle formed by a paste scraping surface of the squeegee and the upper surface of the mask, and moving on the mask The display method of the printing result of Claim 1 including the moving speed which is the speed of a squeegee.
A mask having a pattern hole, and a squeegee moving on the mask, the paste on the mask is filled into the pattern hole by moving the squeegee based on a preset printing condition, and the pattern hole A screen printing method in a screen printing apparatus for transferring the paste filled in the above to a substrate,
The paste is filled in the inspection holes provided in the mask separately from the pattern holes by moving the squeegee with respect to the mask based on preset temporary printing conditions;
Change in pressure of the paste filled in the inspection hole is acquired as a pressure waveform,
The filling pressure and filling time are detected from the pressure waveform,
It is determined whether or not the filling pressure and the filling time satisfy predetermined criteria.
When the determination criteria are satisfied, the temporary printing conditions are set as printing conditions for production;
When the determination criteria are not satisfied, the temporary printing conditions are changed, and based on the changed temporary printing conditions, the process from filling the paste in the inspection hole to determining whether the determination criteria are satisfied is performed again. ,
A screen printing method, wherein the paste on the mask is filled in the pattern holes by moving the squeegee based on the printing conditions for production, and the paste filled in the pattern holes is transferred to the substrate.
If it is determined that the filling time is between the predetermined lower limit time and the upper limit time and the filling pressure is between the predetermined lower limit pressure and the upper limit pressure, it is determined whether the filling time is between the predetermined lower limit pressure and the upper limit pressure. The screen printing method according to claim 6, wherein the determination is made.
The screen printing method according to claim 6, wherein the filling pressure is a maximum value of the pressure in the pressure waveform.
The screen printing method according to claim 6, wherein the filling time is a time at which the pressure exceeding a predetermined threshold in the pressure waveform is detected.
The printing conditions include a printing pressure indicating a force pressing the squeegee against the upper surface of the mask, an attack angle which is an angle formed by a paste scraping surface of the squeegee and the upper surface of the mask, and moving on the mask The screen printing method according to claim 6, wherein the moving speed which is the speed of the squeegee is included.