JP6548040B2 - Electronic component mounting method and mounting apparatus - Google Patents

Description

  The present invention relates to an electronic component mounting method and mounting apparatus for mounting an electronic component while correcting the mounting position of the electronic component.

In recent years, with the progress of miniaturization and high performance of electronic devices represented by smartphones or tablet terminals, densification of electronic parts represented by semiconductor elements used for these terminals and increase in the number of pins of electrode terminals And, the flow of narrowing is accelerating. Therefore, in the mounting apparatus which mounts an electronic component in a board | substrate, mounting with high precision to a board | substrate is calculated | required.
Usually, in order to mount electronic components on a substrate with high accuracy, the mounting apparatus for electronic components is provided with a camera for substrate recognition, and detects the position of the substrate by imaging the substrate with the camera for substrate recognition, Alignment at the time of component mounting is performed based on the position detection result. However, the position of the optical system coordinates of the substrate recognition camera is not necessarily at the position indicated on the control data. For example, an error occurs in a moving mechanism such as a ball screw for moving the camera, or a difference in the amount of thermal expansion due to a temperature difference at each position in the mounting area causes a position shift. Therefore, there is known one having a function of performing so-called calibration for obtaining an amount of unique positional deviation at each position in a mounting area which is an object of electronic component mounting (see, for example, Patent Document 1).
7A and 7B are explanatory diagrams of calibration in the mounting method of the electronic component proposed in Patent Document 1. FIG. The mounting position calibration method will be described with reference to FIGS. 7A and 7B.
FIG. 7A is a plan view of an electronic component mounting apparatus provided with a calibration function. The electronic component mounting apparatus of Patent Document 1 is a camera provided integrally with the mounting head 103 and the mounting head 103 above and adjacent to the component supply unit 105, the substrate conveyance unit 102, and the substrate conveyance unit 102. The mounting head 103 and the camera 104 are integrally moved above the calibration substrate 101 by the X drive axis 106 and the Y drive axis 107. In the calibration substrate 101, recognition marks are formed in advance at positions of measurement points Pi in a lattice shape at a constant interval, and fixed at an arbitrary position on the substrate transport unit 102.
Next, the X drive axis 106 and the Y drive axis 107 are driven to move the camera 104 one by one to a position where the measurement point Pi of the calibration substrate 101 is recognized, and one recognition mark of each measurement point Pi Imaging and recognition one by one.
FIG. 7B is an explanatory view showing the amount of positional deviation between control data at the measurement point Pi and recognition by the camera 104. When the camera 104 is moved to the position of the measurement point Pi, the control data is controlled to move to the position of the origin O of the optical coordinate system, but in the recognition result by the camera 104, the measurement point Pi has coordinates (Δxi , Δyi). By setting the positional deviation amount (Δxi, Δyi) as the unique position error for each measurement point Pi and acquiring the position errors at all measurement points, calibration data of the entire calibration substrate 101 can be obtained.
According to the method described in Patent Document 1, it is supposed that electronic components can be mounted on a substrate with high accuracy by performing position correction and mounting based on calibration data of the entire substrate.

Japanese Patent Laid-Open No. 2002-9495

In order to maintain the high precision mounting of the electronic component even in the steps after mounting, for example, using a thermosetting material such as a die attach film, a die attach paste, an anisotropic conductive adhesive, or a non-conductive adhesive. By mounting while heating the substrate, it is necessary to secure sufficient adhesive strength. However, when the substrate is heated, the temperature distribution in the suction stage for fixing the substrate is nonuniform, so that the stage and the mechanical components in the vicinity of the stage cause nonuniform thermal expansion. In addition, due to the layout of the suction groove of the suction stage, the substrate in the vicinity of the suction groove is shrunk, and the substrate in a portion without the suction groove is expanded, so that the deformation amount of the substrate becomes uneven. In particular, when heating to a high temperature using a large substrate, these tendencies are noticeable.
Therefore, calibration is performed according to the method of Patent Document 1 at normal temperature, and position correction is performed in consideration of the thermal expansion amount obtained by multiplying the thermal expansion coefficient of the substrate by the temperature difference at mounting, and mounting is performed while heating When cooled to room temperature, there has been a problem that the amount of positional deviation from a predetermined mounting position becomes large. In addition, when calibration is performed by the method of Patent Document 1 while heating the stage, the axial gap of the camera or the ball screw driving the stage becomes uneven due to thermal expansion. There is a problem that the position is not stable and the position error of each measurement point becomes large. Furthermore, in order to increase the accuracy of the measurement, the operating speed of each of the X drive axis 106 and the Y drive axis 107 must be reduced, and the measurement must be performed with the vibration of each drive axis settled. The calibration takes time and there is also a problem that it is difficult to apply to the production site.
Furthermore, in order to eliminate errors due to driving of the camera or the stage, the entire image of the calibration substrate 101 is captured using one high pixel and high resolution camera 104 such that the image of the calibration substrate 101 falls within the entire field of view. Even in the case where the camera 104 is moved to a position and an image is taken and the coordinates of the measurement point are calculated from the image, it is difficult to arrange the calibration substrate 101 in a completely perpendicular direction with respect to the optical axis of the camera 104 . The calibration substrate 101 is inclined at an arbitrary angle with respect to the optical axis of the camera 104, and the inclination is further increased by heating of the stage. However, when an image of the calibration substrate 101 is captured by the single camera 104 at normal temperature and heating, respectively, the displacement at each measurement point Pi is determined by the optical axis of the camera 104 and the inclination of the heated calibration substrate 101. It can not be distinguished whether it occurs or is caused by thermal deformation of the calibration substrate 101 itself. Therefore, when position correction is performed based on the displacement of each measurement point Pi in the image based on the difference between normal temperature and heating, there is a problem that the position error at each measurement point Pi becomes extremely large.
Therefore, when mounting an electronic component while heating a substrate due to various factors as described above, positional deviation errors become large, and mounting with high accuracy can not be performed, and calibration can be performed in a short time. could not.
In view of the above problems, the present invention can be mounted with extremely high accuracy by greatly reducing positional deviation error even when mounting an electronic component while heating a substrate, and calibration can be performed in a short time It is an object of the present invention to provide an electronic component mounting method and mounting apparatus.

In order to achieve the above object, an electronic component mounting method according to one aspect of the present invention calculates correction data of a mounting position of the electronic component using a calibration substrate,
Mounting the electronic component on a mounting substrate heated to a mounting temperature at the mounting position based on the correction data;
A mounting method for heating or cooling the mounting substrate on which the electronic component is mounted to a guaranteed temperature,
The correction data of the mounting position is
The calibration substrate is attracted to the stage,
Simultaneously imaging the entire calibration substrate with multiple cameras at the guaranteed temperature ;
Calculating absolute coordinates of a plurality of grid-like squares at predetermined intervals from the plurality of whole images at the guaranteed temperature;
Simultaneously imaging the entire calibration substrate with a plurality of cameras at the mounting temperature;
Calculating absolute coordinates of a grid square corresponding to the plurality of grid squares from the plurality of whole images at the mounting temperature;
It is acquired by calculating the correction amount of the mounting position based on the absolute coordinates of the grid square at the guaranteed temperature and the absolute coordinates of the grid square at the mounting temperature .
Furthermore, according to another aspect of the present invention, there is provided an electronic component mounting apparatus comprising: a mounting head having a function of holding an electronic component and mounting the electronic component at a mounting position of a mounting substrate;
A stage provided so as to face the mounting head and capable of adsorbing the mounting substrate and the calibration substrate, respectively;
A drive mechanism which moves the mounting head or the stage in a lateral direction relatively crossing the vertical direction;
A plurality of cameras having the same resolution, magnification, and focal length, disposed at the same height with respect to the stage so that the entire calibration substrate attracted to the stage can be imaged simultaneously;
A mounting device for an electronic component provided with
Calculating the absolute coordinates of a plurality of grid squares predetermined interval from a plurality of entire images image captured simultaneously respectively by the guarantee temperature and the mounting temperature from said plurality of cameras, the grid square at the guaranteed temperature An image processing apparatus for calculating a correction amount of the mounting position of the electronic component based on an absolute coordinate and an absolute coordinate of a grid square at the mounting temperature ;
Based on the calculated correction amount of the mounting position, the electronic component held by the mounting head is mounted on the mounting position of the mounting substrate attracted to the stage.

  According to the above aspect of the present invention, even when mounting is performed while heating the substrate, it is possible to mount with extremely high accuracy by largely reducing the positional deviation error without recognizing the recognition mark of the mounting substrate each time. And it becomes possible to carry out position correction in a short time.

The schematic block diagram which shows the structure of the mounting apparatus of the electronic component in embodiment of this invention Explanatory drawing which shows the calculation method of the correction amount of the mounting position in embodiment of this invention A plan view showing an example of a pattern of a calibration substrate in the embodiment of the present invention An enlarged plan view showing the pattern of the calibration substrate observed by the first camera at the guaranteed temperature T1 in FIG. 3A An enlarged plan view showing the pattern of the calibration substrate observed by the second camera at the guaranteed temperature T1 in FIG. 3A An enlarged plan view showing the calibration substrate pattern observed by the first camera at mounting temperature T2 in FIG. 3A An enlarged plan view showing the pattern of the calibration substrate observed by the second camera at the mounting temperature T2 in FIG. 3A Process flow chart showing the flow of the method of calculating the correction amount of the mounting position in the embodiment of the present invention Timing chart showing a method of calculating the correction amount of the mounting position in the embodiment of the present invention The schematic block diagram which shows the structure of the mounting apparatus of the electronic component in embodiment of this invention The schematic block diagram which shows the structure of the mounting apparatus of the electronic component in the modification of embodiment of this invention Illustration of calibration in the conventional mounting method of electronic parts A more detailed illustration of the calibration of FIG. 7A

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment
FIG. 1 is a schematic view showing the configuration of an electronic component mounting apparatus according to an embodiment of the present invention. The electronic component mounting apparatus of the present invention shown in FIG. 1 includes at least a mounting head 3, a stage 2, a drive mechanism 8, a camera 4, and an image processing apparatus 5. Furthermore, in FIG. 1, the mounting apparatus includes the supply unit 31 of the electronic component 7.

In this mounting apparatus, correction data of the mounting position of the electronic component 7 is calculated using the calibration substrate 1, and the electronic component 7 is mounted on the mounting substrate 32 heated to the mounting temperature T2 at the mounting position based on the correction data. The mounting substrate 32 on which the electronic component 7 is mounted is heated or cooled to a guaranteed temperature T1.
The mounting head 3 has a function of holding (for example, adsorbing) the electronic component 7 from the supply unit 31 of the electronic component 7 and heating and pressing it to mount the electronic component 7 on the mounting substrate 32 (see FIG. 6A). As an example, the mounting head 3 is movable in the X direction and the Z direction, and the stage 2 is movable in the X direction and the Y direction.

The stage 2 is provided so as to be opposed to the mounting head 3 so that the calibration substrate 1 and the mounting substrate 32 can be individually mounted and adsorbed.
Here, a pattern is provided in advance on the surface of the calibration substrate 1, and the calibration substrate 1 having the pattern is mounted on the stage 2 and adsorbed. The stage 2 is provided with a substrate fixing function by a method of vacuum suction, mechanical fixation or electrostatic suction. The pattern is formed, for example, by plating, sputtering, vapor deposition, ink, or spray, and regular patterns or irregular patterns can be used.
The driving mechanism 8 moves the mounting head 3 independently in the direction along the surface and in the vertical direction perpendicular to the surface with respect to the surface of the plane of the stage 2 respectively. As an example, the drive mechanism 8 can move the mounting head 3 in the X direction and the Z direction, but this is not a limitation, and the mounting head 3 may be movable in the Y direction and the Z direction. The head 3 may be movable in the X direction, the Y direction, and the Z direction. Further, instead of driving the mounting head 3, the driving mechanism 8 may move the stage 2 in the direction along the surface, in other words, in the lateral direction intersecting the vertical direction.
The camera 4 functions as a pair of image pickup devices configured by the first camera 4a and the second camera 4b. The first camera 4 a and the second camera 4 b simultaneously capture an image of a region including at least the same mounting position corresponding portion of the calibration substrate 1 attracted to the stage 2. The first camera 4a and the second camera 4b of the mounting apparatus are at the same height and above the calibration substrate 1 with respect to the calibration substrate 1 at positions where the entire calibration substrate 1 can be imaged simultaneously. Arranged at different angles to the surface. Here, for the first camera 4a and the second camera 4b, lenses of the same magnification and the same focal length are used, and an imaging device such as a CCD or CMOS having the same resolution is used. The pair of cameras 4 simultaneously and collectively capture an image of a pattern of the calibration substrate 1 and an area including at least the same mounting position corresponding portion.

The image processing apparatus 5 has a function of converting information of an image captured by the camera 4 into position coordinates of a mounting position corresponding part.
The image processing device 5 performs image processing on two images simultaneously captured by the pair of cameras 4, and X, Y, Z coordinates of an arbitrary point (for example, a mounting position corresponding portion) Gi on the calibration substrate 1. Finally, the correction amount of the mounting position is acquired. Here, (the image pickup element of) the first camera 4a and the second camera 4b in order to simultaneously pick up an image by the two first cameras 4a and the second camera 4b at an arbitrary point Gi on the calibration substrate 1 And the angle between the straight line heading for an arbitrary point (for example, mounting position corresponding point) Gi and the stage surface, and the distance between the first camera 4a and the second camera 4b (the distance in a plane parallel to the stage surface) The position coordinates of any point Gi can be calculated from Here, i of an arbitrary point Gi is an integer of 1 or more and an integer equal to or less than the total number of arbitrary points of the calibration substrate 1.
According to this method, based on the image information captured by the first camera 4 a and the second camera 4 b with respect to the calibration substrate 1, the image processing apparatus 5 can calculate position coordinates with high accuracy. . In addition, when the imaging timing is not simultaneous but temporally deviated by the two first and second cameras 4a and 4b, the calculated variation in position may be caused by vibration or vibration of the calibration substrate 1 or temperature change. growing. On the other hand, by simultaneously imaging with the two first and second cameras 4a and 4b, it is possible to calculate the position with high accuracy by eliminating the variation.
According to the present embodiment, the first and second cameras 4a and 4b can be installed at an angle with respect to the calibration substrate 1, and the two first and second cameras can be installed in the limited space of the mounting apparatus. There is also an effect that the freedom of arranging the cameras 4a and 4b is increased, and the design of the mounting device becomes easy.

The correction data of the mounting position used in the mounting method in the embodiment of the present invention is
The calibration substrate 1 is attracted to the stage 2,
Images of an area 43 including at least the same mounting position corresponding portion Gi of the calibration substrate 1 are simultaneously captured by a plurality of cameras 4a and 4b;
The correction amount of the mounting position is calculated based on the information of the mounting position corresponding portion Gi in the area 43 from the plurality of images simultaneously captured by the plurality of cameras 4a and 4b. The details will be described below.

FIG. 2 is an explanatory view showing a method of calculating the correction amount of the mounting position in the embodiment of the present invention. A method of mounting the electronic component 7 on the mounting substrate 32 while correcting the mounting position at the mounting temperature T2 so that the distance between the electronic components 7 becomes a constant interval at a guaranteed temperature T1 lower than the mounting temperature T2 will be described. Hereinafter, the case where the distance between the electronic components 7 at the guaranteed temperature T1 is Px and Py in the X direction and the Y direction will be described.
First, after the image of the entire calibration substrate 1 is simultaneously captured by the first camera 4a and the second camera 4b at the guaranteed temperature T1, the image processing device 5 captures the image of the calibration substrate 1 captured by the first camera 4a. , And in the X direction and in the Y direction at intervals of Px and Py, respectively.
Next, in the image processing apparatus 5, an image equivalent to the image of the area in the vicinity of the vertex at all the vertices of the grid 42 in the first camera 4a (for example, an image of the area where the patterns are similar to each other ) Is detected from the image simultaneously captured by the second camera 4b by processing such as pattern matching, and in the image captured by the second camera 4b, the image captured by the first camera 4a is X direction and Y direction The coordinates corresponding to the vertexes of the grid 42 divided by intervals of Px and Py respectively are calculated. The image processing apparatus 5 calculates absolute coordinates based on the coordinates calculated by the first camera 4a and the second camera 4b at all the vertices of the grid. Here, let us say that the center of gravity of the quadrangle A1B1C1D1 surrounded by the lattice vertices A1, B1, C1, and D1 is a point Gi1. Here, as an example, each barycentric position is a mounting position corresponding place corresponding to the mounting position of the mounting substrate 32.

Next, also at the mounting temperature T2, similarly to the guaranteed temperature T1, after the images of the entire calibration substrate 1 are simultaneously captured one by one by the first camera 4a and the second camera 4b, the image processing device 5 performs image processing The image processing device 5 converts the vertexes of the grid to absolute coordinates. In the image processing device 5, after the quadrangle A1B1C1D1 at the guarantee temperature T1 is deformed to the quadrangle A2B2C2D2 at the mounting temperature T2 by an image processing method such as luminance distribution analysis, the barycentric position Gi2 of the quadrangle A2B2C2D2 is calculated. In the image processing device 5, the difference between the gravity center position Gi2 at the mounting temperature T2 and the gravity center position Gi1 at the guarantee temperature T1 is the correction amount of the mounting position corresponding portion, in other words, the correction amount of the mounting position on the mounting substrate 32.
Thus, the position correction amount can be calculated by the image processing device 5.

Therefore, when mounting electronic components 7 such as semiconductor elements on a mounting substrate 32 such as a circle or rectangle at a mounting temperature T2 so as to be arranged in a lattice at intervals of Px and Py in the X and Y directions, respectively. A position obtained by adding the above-described position correction amount to the barycentric position of the grid square may be mounted as a mounting position. When the mounting substrate 32 is returned from the mounting temperature T2 to the guaranteed temperature T1 after mounting, the distances between the centers of the electronic components 7 are equal intervals of Px and Py in the X direction and the Y direction, respectively.
According to this mounting method, since the deformation amount of the calibration substrate 1 at the mounting temperature T2 is calculated at all mounting positions, the electronic components 7 can be mounted on the mounting substrate 32 at equal intervals.

An example in which the calculation of the correction amount of FIG. 2 is more specifically applied to the calibration substrate 1 will be described. FIG. 3A is a plan view showing an example of a pattern of the calibration substrate 1 according to the embodiment of the present invention. In the vicinity of one vertex A1 of the quadrangle A1B1C1D1 on the calibration substrate 1, a speckled pattern 40 is formed as an example of the irregular pattern.
First, at the guaranteed temperature T1, images are simultaneously captured by the first camera 4a and the second camera 4b and observed as images in the vicinity of the vertex A1 as shown in FIGS. 3B and 3C. In FIG. 3B, the image processing apparatus 5 calculates the barycentric position of the pattern of the area 43 surrounded by the solid frame 41 in FIG. 3B as A1a. Here, the area 43 surrounded by the frame 41 is an area including a barycentric position A1a which is an example of the mounting position corresponding portion.
Next, in FIG. 3C, the image processing apparatus 5 detects a spotted pattern equivalent to the spotted pattern of the area 43 surrounded by the solid frame 41 in FIG. 3B by pattern matching and the like, and the barycentric position thereof is A1b. The image processing apparatus 5 calculates the When the calibration substrate 1 itself is deformed at the mounting temperature T2 due to heating or adsorption fixation at the mounting temperature T2, the pattern on the surface is also deformed following the deformation of the calibration substrate 1 itself.

  Next, the images are simultaneously captured by the first camera 4a and the second camera 4b at the mounting temperature T2, and are observed as shown in FIGS. 3D and 3E as images near the vertex A1, respectively. Here, the pattern of the area 43 surrounded by the solid frame 41 in FIGS. 3B and 3C moves to the area 43 surrounded by the solid frame 41 in FIGS. 3D and 3E, respectively. The barycentric positions change from A1a and A1b to A2a and A2b, respectively. The two first and second cameras 4a and 4b appear to be displaced in different directions, but the coordinates of the barycentric positions A1a, A1b, A2a and A2b and the distance between the first camera 4a and the second camera 4b From the first camera 4a and the second camera 4b toward the calibration substrate 1 and the respective angles formed with the surface of the stage 2, the absolute coordinates of the vertices A1 and A2 are calculated by the image processing device 5, Since the difference is derived by the image processing device 5 as the displacement amount (ΔX, ΔY) of the vertex A1, the displacement amount (correction amount of position coordinates) can be calculated by the image processing device 5 with high accuracy. Similar to the vertex A1, the image processing device 5 derives the displacement amount of the coordinates of each vertex (the correction amount of the position coordinates) by analyzing all the vertices of the lattice on the calibration substrate 1 by the image processing device 5. Can. Although the case of using the digital image correlation method in the image processing apparatus 5 has been described, the present invention is not limited to this method. A general image analysis method may be used in the image processing device 5.

FIG. 4 is a process flow diagram showing a flow of a method of calculating the correction amount of the mounting position in the embodiment of the present invention. FIG. 5 is a timing chart showing a method of calculating the correction amount of the mounting position in the embodiment of the present invention. FIG. 6A is a schematic configuration view showing a configuration of the electronic component mounting apparatus according to the embodiment. A method of calculating the mounting correction amount will be described based on FIGS. 1 and 4 and FIGS. 5 and 6A.
First, in step S1, the calibration substrate 1 stored in the substrate storage unit (not shown) is taken out of the substrate storage unit using a transport jig (not shown) and placed on the stage 2. Here, vacuum suction of the calibration substrate 1 by the stage 2 is not performed. The calibration substrate 1 is made of, for example, silicon, glass, stainless steel, or copper. The external dimensions of the calibration substrate 1 are, for example, 200 mm × 200 mm to 600 mm × 600 mm, and for example, a spotted pattern is formed on the surface of the calibration substrate 1.
Next, in step S2, at time t11 when the temperature of the calibration substrate 1 reaches the guarantee temperature T1, images C11A and C11B of the entire calibration substrate 1 are simultaneously imaged using the first camera 4a and the second camera 4b. . Here, the guaranteed temperature T1 is 25 ° C., for example.

Thereafter, in step S3, the stage 2 is heated to at least the mounting temperature T2, and then the vacuum suction device 10 connected to the plurality of suction grooves 2a of the stage 2 is turned on to suction the calibration substrate 1 onto the stage 2; The calibration substrate 1 is fixed to the stage 2.
Next, in step S4, the images C21A and C21B of the entire calibration substrate 1 are simultaneously imaged using the first camera 4a and the second camera 4b at time t21 when the calibration substrate temperature becomes the mounting temperature T2. The data of the image captured in step S2 and step S4 is taken into the image processing device 5. Each image simultaneously captured by the first camera 4a and the second camera 4b may include an image of an area including at least the same mounting position corresponding portion.
Thereafter, in step S5, the calibration substrate 1 is removed from the stage 2 and stored in the substrate storage unit.

  After that, when repeating the same process as step S3 and step S4, in step S8, as in step S1, the calibration substrate 1 stored in the substrate storage unit is taken out from the substrate storage unit using the transport jig, After mounting on the stage 2, steps S3 to S5 are performed. For example, when performing step S3 and step S4 twice, the images C22A and C22B and the images C23A and C23B of the entire calibration substrate 1 are simultaneously captured using the first camera 4a and the second camera 4b at times t22 and t23, respectively. After that, they are taken into the image processing device 5. Here, the mounting temperature T2 is 150 ° C., for example.

Next, in step S6, using the image processing device 5, the images C11A and C11B, the images C21A and C21B1, the images C22A and C22B, and the images C23A and C23B are converted into vertex coordinates of the grid 42, and then the calculation of the center of gravity is performed. Based on the method, position coordinates (X1Gi, Y1Gi) of the mounting position corresponding portion at the guaranteed temperature T1 and time t11, and position coordinates (X2Gi1, Y2Gi1) of the mounting position corresponding portion at the mounting temperature T2 and time t21, t22, t23, ( The image processing apparatus 5 derives X2Gi2, Y2Gi2) and (X2Gi3, Y2Gi3). Further, in the image processing apparatus 5, the position coordinates (X2Gi1, Y2Gi1), (X2Gi2, Y2Gi2), and (X2Gi3, Y2Gi3) of the mounting position corresponding portion are averaged to obtain the position coordinate (X2Gi) of the mounting position corresponding portion at the mounting temperature T2. , Y2Gi).
Further, in step S7, the position coordinates (X1Gi, Y1Gi) of the mounting position corresponding portion at the guaranteed temperature T1 are drawn from the position coordinates (X2Gi, Y2Gi) of the mounting position corresponding portion at the mounting temperature T2, and the position for each mounting position corresponding portion The correction amount (Δxi, Δyi) is calculated by the image processing device 5.
The above is the method of deriving the position correction amount by the image processing device 5.
In the above embodiment, although the case of once at the guarantee temperature T1 and three cases of the mounting temperature T2 has been described, the invention is not limited thereto. In the case of one mounting temperature T2, the position correction amount can be derived in a short time.

Further, by repeating adsorption and removal of the calibration substrate 1 to increase the number of times of capturing an image, there is an effect that the position correction accuracy is further improved. Moreover, although the calibration board | substrate 1 described the method to adsorb | suck the calibration board | substrate 1 by a conveyance jig using a board | substrate storage unit, it is not restricted to this. Even if the calibration substrate 1 is manually removed from the stage 2 and placed on the stage 2 and adsorbed, the same effect can be obtained.
When the mounting substrate 32 is heated, not only the mounting substrate 32 is warped but also when the mounting substrate 32 is adsorbed to the stage 2 in the mounting process, the adsorption position varies, so the mounting substrate 32 is There is variation in deformation. By repeatedly sucking and removing the calibration substrate 1 and capturing an image a plurality of times, it is possible to calculate an average value in consideration of the variation in the position corresponding to the mounting position, which has an effect of further improving the position correction accuracy.

  In addition, when the temperature of the guaranteed temperature T1 or the mounting temperature T2 is high, the air in the vicinity of the calibration substrate is heated by radiant heat to cause temperature variation of the air, and when capturing an image with the camera 4, the air fluctuates like a bright flame It is distorted. In such a case, the image may be captured and averaged multiple times. According to this structure, high position correction accuracy can be ensured even if the calibration substrate 1 is at high temperature.

Next, a method of mounting the electronic component on the mounting substrate 32 by using the method of deriving the position correction amount will be described. The position of the coordinates (xi + Δxi, yi + Δyi) obtained by adding the position correction amount (Δxi, Δyi) obtained by the image processing apparatus 5 to the design coordinates (xi, yi) of each mounting position at mounting temperature T2 at mounting The coordinates of each mounting position become (xi, yi) when the temperature is returned to the guaranteed temperature T1.
An example will be described based on a specific embodiment. When the semiconductor element as the electronic component 7 is mounted on a circular mounting substrate 32 having an outer dimension of 300 mm in diameter, 0.7 mm in thickness, and a linear expansion coefficient of 8 ppm / ° C. (ie, μm / ° C./m) Will be explained. The semiconductor elements are 10 mm × 10 mm and 0.3 mm in thickness, and the designed pitch between semiconductor elements is 15 mm. By using the first camera 4a and the second camera 4b each having 5 million pixels, the change of the pattern on the calibration substrate 1 can be determined by the adsorption OFF state at 30.degree. C. and the stage 2 at 150.degree. Images were taken simultaneously in the state of suction ON. It was found from the image analysis by the image processing device 5 that positional deviations of up to 130 to 160 μm occur at 30 ° C. and 150 ° C. The position correction amount at the mounting position of 15 mm pitch is determined by the image processing apparatus 5 by image processing, and the mounting substrate 32 is maintained at 150 ° C. by heating or cooling at the mounting position where the position correction amount is added. The mounting was done with the mounting device.

Thereafter, the mounting substrate 32 was removed from the stage 2 and the amount of positional deviation of the mounting position of the electronic component relative to the design value was measured at 30 ° C. using a measuring microscope. As a result, it was confirmed that the mounting positional deviation amount was within ± 3 μm in both the x and y directions with respect to 200 mounting positions. The images were simultaneously captured by one first at 30 ° C., three at 150 ° C., and two first and second cameras 4a and 4b, but each image could be captured within a short time of 10 ms.
Although the case where the camera 4 is comprised by two cameras 4a and 4b was demonstrated in the above embodiment, it is not restricted to this. Three or more cameras 4 may be used. For example, FIG. 6B is a schematic configuration view showing a configuration of the mounting apparatus of the electronic component in the modification of the embodiment of the present invention. The camera 4 is different from the mounting apparatus of FIG. 1 in that the camera 4 is composed of three cameras, ie, camera first to third cameras 4a, 4b and 4c. The obstacle 6 is formed of, for example, a pillar or a partition. The point Gia, which is an example of the mounting position corresponding portion on the calibration substrate 1, is simultaneously imaged by the first camera 4a and the second camera 4b. The point Gib which is another example of the mounting position corresponding portion on the calibration substrate 1 is blocked by the obstacle 6 and can not be imaged from the first camera 4a, but from the positions of the second camera 4b and the third camera 4c Images can be taken simultaneously. By compensating the area which can not be imaged by the first camera 4a and the second camera 4b with the third camera 4c, the correction amount of the mounting position of the entire calibration substrate 1 can be calculated. It becomes possible to implement to accuracy. In particular, there is an effect that the present invention can be applied to a mounting substrate 32 that is larger than the mounting device of FIG.

As described above, according to the embodiment of the present invention, in the case of mounting the electronic component 7 while heating the mounting substrate 32, even if the mounting substrate 32 is not provided with the recognition mark, the positional deviation error is largely reduced. Thus, it is possible to perform mounting on the mounting substrate 32 with high accuracy by performing position correction (calibration) in a short time.
The present invention is not limited to the above embodiment, and can be implemented in various other aspects. For example, the irregular pattern is not limited to spots, but may be any irregular pattern such as a shape, a pattern, or a pattern. In the case of any irregular pattern, there is an advantage that the mounting position corresponding part can be calculated from any part. Also, instead of the irregular pattern, any shape, pattern, or regular pattern such as a pattern may be used.
In addition, the effect which each has can be show | played by combining suitably the arbitrary embodiment or modification of said various embodiment or modification. Further, a combination of the embodiments or a combination of the embodiments or a combination of the embodiments and the embodiments is possible, and a combination of the features in different embodiments or the embodiments is also possible.

  The electronic component mounting method and mounting apparatus according to the above aspect of the present invention has the effect of being able to mount the electronic component with extremely high accuracy while heating the substrate, and of performing calibration in a short time, and at high speed The present invention is particularly useful in a mounting method and mounting apparatus of a semiconductor device such as a large capacity memory, an application processor, a CPU, or a high frequency communication module.

DESCRIPTION OF SYMBOLS 1, 101 Calibration board | substrate 2 Stage 2a Suction groove 3, 103 Mounting head 4, 4a, 4b, 4c, 104 Camera 5 Image processing apparatus 6 Obstacle 7 Electronic parts 8 Drive mechanism 10 Vacuum suction apparatus 31 Supply part 32 of electronic parts Mounting substrate 40 Speckled pattern 41 Frame 42 Lattice 43 Area 102 Substrate transfer part 105 Component supply part 106 X drive axis 107 Y drive axis

Claims (3)

Calculate correction data of the mounting position of the electronic component using the calibration substrate,
Mounting the electronic component on a mounting substrate heated to a mounting temperature at the mounting position based on the correction data;
A mounting method for heating or cooling the mounting substrate on which the electronic component is mounted to a guaranteed temperature,
The correction data of the mounting position is
The calibration substrate is attracted to the stage,
Simultaneously imaging the entire calibration substrate with multiple cameras at the guaranteed temperature ;
Calculating absolute coordinates of a plurality of grid-like squares at predetermined intervals from the plurality of whole images at the guaranteed temperature;
Simultaneously imaging the entire calibration substrate with a plurality of cameras at the mounting temperature;
Calculating absolute coordinates of a grid square corresponding to the plurality of grid squares from the plurality of whole images at the mounting temperature;
The mounting method of the electronic component acquired by calculating the correction amount of the said mounting position based on the absolute coordinate of the grid | lattice square at the said guarantee temperature, and the absolute coordinate of the grid square at the said mounting temperature .   After suctioning the calibration substrate, the images are simultaneously captured by the plurality of cameras, and after releasing the suction of the calibration substrate and re-sucking, the images are simultaneously captured by the plurality of cameras. The electronic component mounting method according to claim 1, wherein the correction amount of the mounting position is calculated based on the images captured a plurality of times by the plurality of cameras. A mounting head having a function of holding electronic components and mounting them at the mounting position of the mounting substrate;
A stage provided so as to face the mounting head and capable of adsorbing the mounting substrate and the calibration substrate, respectively;
A drive mechanism which moves the mounting head or the stage in a lateral direction relatively crossing the vertical direction;
A plurality of cameras having the same resolution, magnification, and focal length, disposed at the same height with respect to the stage so that the entire calibration substrate attracted to the stage can be imaged simultaneously;
A mounting device for an electronic component provided with
Calculating the absolute coordinates of a plurality of grid squares predetermined interval from a plurality of entire images image captured simultaneously respectively by the guarantee temperature and the mounting temperature from said plurality of cameras, the grid square at the guaranteed temperature An image processing apparatus for calculating a correction amount of the mounting position of the electronic component based on an absolute coordinate and an absolute coordinate of a grid square at the mounting temperature ;
The mounting apparatus of the electronic component which mounts the said electronic component hold | maintained by the said mounting head on the said mounting position of the said mounting board attracted | sucked to the said stage based on the correction amount of the calculated said mounting position.

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