JP2018041802A - Mounting method and mounting apparatus for electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting method and apparatus for an electronic component such that the electronic component when mounted while a mounting substrate is heated can be mounted on the mounting substrate by making position corrections with very high precision in a short time.SOLUTION: A mounting apparatus comprises: a mounting head 3 which holds and mounts an electronic component 7 at a mounting position on a mounting substrate 32; a stage 2 which faces the mounting head, and can suck or attract the mounting substrate and a calibration substrate; a drive mechanism 8 which relatively moves the mounting head or stage in a lateral direction crossing an up/down direction; and a plurality of cameras 4a, 4b capable of simultaneously picking up images of a region 43 including at least the same mounting position corresponding places Gi of the calibration substrate sucked or attracted to the stage. The mounting apparatus comprises an image processing unit 5 which calculates a correction quantity for the mounting position of an electronic component from information on mounting position corresponding places of a plurality of images picked up simultaneously by the plurality of cameras, and mounts the electronic component at the mounting position of the mounting substrate based upon the correction quantity.SELECTED DRAWING: Figure 1

Description

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

In recent years, with the progress of downsizing and higher performance of electronic devices typified by smartphones or tablet terminals, the density of electronic components typified by semiconductor elements used in these terminals has been increased, and the number of pins of electrode terminals has been increased. And the flow of narrowing the pitch is accelerating. Therefore, in a mounting apparatus that mounts electronic components on a substrate, it is required to mount the substrate on the substrate with high accuracy.
Usually, in order to mount an electronic component on a substrate with high accuracy, the electronic component mounting apparatus includes a substrate recognition camera, detects the position of the substrate by imaging the substrate with the substrate recognition camera, Based on the result of position detection, alignment at the time of component mounting is performed. However, the position of the optical system coordinates of the substrate recognition camera is not always at the position indicated on the control data. For example, an error of a moving mechanism such as a ball screw that moves the camera occurs, or a difference in thermal expansion occurs due to a temperature difference at each position in the mounting area, thereby causing a positional shift. For this reason, a device having a function of performing a so-called calibration for obtaining a specific positional deviation amount at each position in a mounting area to be electronic component mounted is known (see, for example, Patent Document 1).
7A and 7B are explanatory diagrams of calibration in the electronic component mounting method proposed in Patent Document 1. FIG. A 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 having a calibration function. The electronic component mounting apparatus disclosed in Patent Document 1 includes a component supply unit 105, a substrate transport unit 102, and a mounting head 103 and a camera provided adjacent to and integrated with the mounting head 103 above the substrate transport unit 102. 104, and the mounting head 103 and the camera 104 are moved together above the calibration substrate 101 by the X drive shaft 106 and the Y drive shaft 107. On the calibration substrate 101, recognition marks are formed in advance at the positions of the measurement points Pi at a predetermined pitch in a grid pattern, and are fixed at an arbitrary position on the substrate transport unit 102.
Next, the X drive shaft 106 and the Y drive shaft 107 are driven to move the camera 104 one by one to a position where the measurement point Pi on the calibration substrate 101 is recognized, and one recognition mark for each measurement point Pi is obtained. Capture and recognize one by one.
FIG. 7B is an explanatory diagram showing the amount of positional deviation between the control data at the measurement point Pi and the recognition by the camera 104. When the camera 104 is moved to the position of the measurement point Pi, the control data is controlled so as to move to the position of the origin O of the optical coordinate system. However, according to the recognition result by the camera 104, the measurement point Pi has coordinates (Δxi). , Δyi). By using this positional deviation amount (Δxi, Δyi) as a unique position error for each measurement point Pi, and acquiring position errors at all measurement points, calibration data for the entire calibration substrate 101 can be obtained.
According to the method described in Patent Document 1, it is supposed that an electronic component can be mounted on a substrate with high accuracy by correcting the position based on calibration data of the entire substrate and mounting.

JP 2002-9495 A

In order to maintain high-precision mounting of electronic components even after the mounting process, for example, a thermosetting material such as a die attach film, a die attach paste, an anisotropic conductive adhesive, or a non-conductive adhesive is used. It is necessary to ensure sufficient adhesive strength by mounting the substrate while heating. However, when the substrate is heated, the temperature distribution in the suction stage for fixing the substrate is non-uniform, so that non-uniform thermal expansion occurs in the stage and the mechanical components near the stage. In addition, due to the layout of the suction grooves of the suction stage, the amount of deformation of the substrate becomes non-uniform such that the substrate in the vicinity of the suction groove contracts and the substrate without the suction groove expands. In particular, when a large substrate is used and heated to a high temperature, these tendencies are noticeable.
For this purpose, even if the calibration is performed at room temperature by the method of Patent Document 1, the position is corrected by taking into account the thermal expansion coefficient obtained by multiplying the thermal expansion coefficient of the substrate by the temperature difference at the time of mounting, and mounting while heating When cooled to room temperature, there is a problem that the amount of displacement from a predetermined mounting position increases. Further, when calibration is performed by the method of Patent Document 1 while the stage is heated, the axial gap of the ball screw that drives the camera or the stage becomes non-uniform due to thermal expansion. There is a problem that the position error of each measurement point becomes large without being stabilized. Furthermore, in order to increase the measurement accuracy, it is necessary to reduce the operation speed of each of the X drive shaft 106 and the Y drive shaft 107 and perform measurement in a state where the vibrations of the respective drive shafts are suppressed. There was also a problem that calibration took time and was difficult to apply to the production site.
Further, in order to eliminate an error caused by driving of the camera or the stage, one high pixel and high resolution camera 104 in which the image of the calibration substrate 101 falls within the entire field of view is used, and the entire image of the calibration substrate 101 is reflected. Even when the camera 104 is moved to a position, an image is captured, and the coordinates of the measurement point are calculated from the image, it is difficult to arrange the calibration substrate 101 in a completely vertical direction with respect to the optical axis of the camera 104. . The calibration substrate 101 tilts at an arbitrary angle with respect to the optical axis of the camera 104, and the tilt is further increased by heating the stage. However, when the image of the calibration substrate 101 is captured by the single camera 104 at normal temperature and when heated, the displacement at each measurement point Pi depends on the optical axis of the camera 104 and the tilt of the heated calibration substrate 101. It cannot be distinguished whether it is caused by thermal deformation of the calibration substrate 101 itself. Therefore, there is a problem that when the position is corrected by the difference between the normal temperature and the heating based on the displacement of each measurement point Pi in the image, the position error at each measurement point Pi becomes extremely large.
Therefore, due to various factors as described above, when mounting an electronic component while heating the substrate, the displacement error becomes large, mounting with high accuracy is impossible, and calibration can be performed in a short time. could not.
In view of the above problems, the present invention can be mounted with very high accuracy by greatly reducing misalignment error and can be calibrated in a short time even when mounting electronic components while heating the substrate. An object of the present invention is to provide a mounting method and a mounting apparatus for electronic components.

In order to achieve the above object, an electronic component mounting method according to one aspect of the present invention calculates correction data for a mounting position of an electronic component using a calibration board,
At the mounting position based on the correction data, the electronic component is mounted on a mounting substrate heated to a mounting temperature,
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
Adsorb the calibration substrate on the stage,
Simultaneously capturing an image of a region including at least the same mounting position corresponding portion of the calibration board by a plurality of cameras,
It is obtained by calculating a correction amount of the mounting position from a plurality of images simultaneously captured by the plurality of cameras, based on information on the mounting position corresponding portion in the region.
Furthermore, an electronic component mounting apparatus according to another aspect of the present invention includes a mounting head having a function of holding an electronic component and mounting it on 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,
A driving mechanism that moves the mounting head or the stage in a lateral direction that intersects the vertical direction relatively;
The resolution, magnification, and focal length arranged at the same height with respect to the stage so that an image of an area including at least the same mounting position corresponding portion of the calibration board adsorbed to the stage can be simultaneously captured. The same cameras,
An electronic component mounting apparatus comprising:
An image processing apparatus that calculates a correction amount of the mounting position of the electronic component corresponding to the mounting position corresponding location from information on the mounting position corresponding location of a plurality of images simultaneously captured from the plurality of cameras;
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 board attracted to the stage.

  According to the aspect of the present invention, even when the substrate is mounted while being heated, it can be mounted with very high accuracy by greatly reducing the misalignment error without recognizing the recognition mark of the mounting substrate every time. In addition, position correction can be performed in a short time.

1 is a schematic configuration diagram showing a configuration of an electronic component mounting apparatus according to an embodiment of the present invention. Explanatory drawing which shows the calculation method of the correction amount of the mounting position in embodiment of this invention The top view which shows the example of the pattern of the calibration board | substrate in embodiment of this invention Enlarged plan view showing a pattern of a calibration substrate that has been observed by the first camera guaranteed temperatures T ₁ in FIG. 3A Enlarged plan view showing a pattern of a calibration substrate that has been observed by the second camera guaranteed temperatures T ₁ in FIG. 3A 3A is an enlarged plan view showing the pattern of the calibration board observed by the first camera at the mounting temperature T ₂ in FIG. 3A. 3A is an enlarged plan view showing the pattern of the calibration board observed by the second camera at the mounting temperature T ₂ in FIG. 3A. Process flow diagram showing a flow of a mounting position correction amount calculation method in an 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 1 is a schematic configuration diagram showing a configuration of an electronic component mounting apparatus according to an embodiment of the present 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 Explanatory drawing of calibration in the conventional electronic component mounting method 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 configuration diagram showing a configuration of an electronic component mounting apparatus according to an embodiment of the present invention. The electronic component mounting apparatus according to 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 device 5. Further, in FIG. 1, the mounting apparatus includes a supply unit 31 for the electronic component 7.
In this mounting apparatus calculates the correction data of the mounting position of the electronic component 7 by using the calibration substrate 1, the mounting position based on the correction data, mounting the electronic component 7 mounted temperature T ₂ until heated mounting substrate 32 and is for heating or cooling the mounting board 32 on which electronic components 7 are mounted on guarantee temperature T _1.
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 mounting it on the mounting substrate 32 (see FIG. 6A) by heating and pressing. 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 able to face the mounting head 3 so that the calibration substrate 1 and the mounting substrate 32 can be individually placed and sucked.
Here, a pattern is provided in advance on the surface of the calibration substrate 1, and the calibration substrate 1 having the pattern is placed on the stage 2 and sucked. The stage 2 is provided with a substrate fixing function by vacuum suction, mechanical fixing, or electrostatic chucking. The pattern is formed by, for example, plating, sputtering, vapor deposition, ink, or spray, and a regular pattern or an irregular pattern can be used.
The driving mechanism 8 independently moves the mounting head 3 in the direction along the surface and in the vertical direction perpendicular to the surface with respect to the planar surface of the stage 2. As an example, the drive mechanism 8 can move the mounting head 3 in the X direction and the Z direction, but is not limited thereto, 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 a direction along the surface, in other words, in a lateral direction intersecting the vertical direction.
The camera 4 functions as a pair of image capturing devices configured by the first camera 4a and the second camera 4b. The first camera 4a and the second camera 4b simultaneously capture an image of an area including at least the same mounting position corresponding portion of the calibration board 1 sucked on the stage 2. The first camera 4a and the second camera 4b of the mounting apparatus are positioned at the same height above the calibration substrate 1 and at the same level relative to the calibration substrate 1 at positions where the entire calibration substrate 1 can be simultaneously imaged. Arranged at different angles to the surface. Here, for the first camera 4a and the second camera 4b, lenses having the same magnification and the same focal length and the same resolution, for example, an image sensor such as a CCD or a CMOS are used. A pair of cameras 4 captures images of the pattern of the calibration substrate 1 at the same time, together with images of a region including at least the same mounting position corresponding portion.
The image processing device 5 has a function of converting the information of the image captured by the camera 4 into position coordinates corresponding to the mounting position.
The image processing apparatus 5 performs image processing on two images simultaneously captured by the pair of cameras 4, and sets an arbitrary point (for example, a mounting position corresponding location) Gi on the calibration substrate 1 as an X, Y, Z coordinate. Finally, the correction amount of the mounting position is acquired. Here, since the first camera 4a and the second camera 4b simultaneously capture an image of an arbitrary point Gi on the calibration substrate 1, the first camera 4a and the second camera 4b (imaging elements thereof). And an angle formed between a straight line from an arbitrary point (for example, a position corresponding to the mounting position) Gi and the stage surface, and a distance between the first camera 4a and the second camera 4b (a distance in a plane parallel to the stage surface) From this, the position coordinates of an arbitrary point Gi can be calculated. Here, i at an arbitrary point Gi is an integer equal to or greater than 1, and is an integer equal to or smaller than the total number of arbitrary points on the calibration substrate 1.
According to this method, it is possible to calculate the position coordinates with high accuracy by the image processing device 5 based on the image information captured by the first camera 4a and the second camera 4b on the calibration substrate 1. . In addition, if the timing of imaging is not simultaneous but is shifted in time by the two first and second cameras 4a and 4b, variation in the calculated position is caused by vibration or shaking of the calibration substrate 1 or a temperature change. growing. On the other hand, by simultaneously capturing images with the two first and second cameras 4a and 4b, it is possible to calculate the position with high accuracy without the variation.
According to the present embodiment, the first and second cameras 4a and 4b can be installed to be inclined with respect to the calibration board 1, and the two first and second cameras can be installed in a limited space of the mounting apparatus. There is an effect that the degree of freedom of arranging the cameras 4a and 4b is increased, and the design of the mounting apparatus is facilitated.
Mounting position correction data used in the mounting method according to the embodiment of the present invention is:
Adhere the calibration substrate 1 to the stage 2,
A plurality of cameras 4a, simultaneously captures an image of a region 43 including at least the same mounting position corresponding part G _i of the calibration substrate 1 by 4b,
A plurality of cameras 4a, a plurality of images captured simultaneously 4b, based on the information of the mounting position corresponding part G _i of the region 43, and calculates the correction amount of the mounting position. Details will be described below.
FIG. 2 is an explanatory diagram illustrating a method of calculating the mounting position correction amount according to the embodiment of the present invention. A method for mounting the electronic component 7 on the mounting substrate 32 while correcting the mounting position at the mounting temperature T ₂ so that the distance between the electronic components 7 becomes a constant interval at the guaranteed temperature T ₁ lower than the mounting temperature T ₂ will be described. To do. Hereinafter, description will be given of a case where the interval between the electronic components 7 of the guaranteed temperature T ₁ is, it becomes Px and Py, respectively X and Y directions.
First, guaranteed after simultaneously captures an image of the entire calibration substrate 1 by the first camera 4a and the second camera 4b at the temperature T _1, in the image processing apparatus 5, a calibration image of the substrate 1 taken by the first camera 4a Are divided in a lattice pattern at intervals of Px and Py in the X direction and the Y direction, respectively.
Next, in the image processing device 5, an image equivalent to an image in the vicinity of the vertex at all the vertices of the grid 42 in the first camera 4 a (for example, an image of an area having similar patterns as described later with reference to FIG. 3A and the like). ) Is detected from an image simultaneously captured by the second camera 4b, for example, 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 detected in the X direction and the Y direction. The coordinates corresponding to the vertices of the grid 42 divided by the intervals of Px and Py are calculated. The absolute coordinates are calculated by the image processing device 5 based on the coordinates calculated by the first camera 4a and the second camera 4b at all the vertices of the lattice. Here, the position of the center of gravity of the quadrangle A ₁ B ₁ C ₁ D ₁ surrounded by the vertices A _1, B _1, C _{1 and} D ₁ of the lattice is defined as a point G _i1 . Here, as an example, each barycentric position is a mounting position corresponding position corresponding to the mounting position of the mounting board 32.
Next, at the mounting temperature T ₂ , as with the guaranteed temperature T ₁ , after the images of the entire calibration board 1 are taken simultaneously by the first camera 4 a and the second camera 4 b, the image is processed by the image processing device 5. Processing is performed, and the image processing device 5 converts the vertexes of the grid into absolute coordinates. In the image processing apparatus 5, the square A ₁ B ₁ C ₁ D _{1 at} the guaranteed temperature T ₁ is transformed into the square A ₂ B ₂ C ₂ D _{2 at} the mounting temperature T ₂ by an image processing method such as luminance distribution analysis. , The center-of-gravity position G _i2 of the quadrangle A ₂ B ₂ C ₂ D ₂ is calculated. In the image processing apparatus 5, the difference between the center of gravity position G _{i2 at} the mounting temperature T _{2 and} the center of gravity position G _i1 at the guaranteed temperature T ₁ is the correction amount of the mounting position corresponding portion, in other words, the correction of the mounting position on the mounting substrate 32. It becomes quantity.
In this way, the position correction amount can be calculated by the image processing device 5.
Therefore, the electronic component 7 such as a semiconductor element, the mounting substrate 32 such as circular or rectangular, so as to be arranged in a grid at intervals of Px and Py, respectively X and Y directions, implemented in mounting temperature T ₂ In this case, a position obtained by adding the above-described position correction amount to the barycentric position of the lattice-like square may be mounted as the mounting position. After the mounting, when returning the mounting substrate 32 from the mounting temperature T ₂ in the guarantee temperature T _1, the distance between the centers of the electronic component 7 is made at equal intervals Px and Py, respectively X and Y directions.
According to this technique, in order to calculate the deformation amount of the calibration substrate 1 at mounting temperature T ₂ at all mounting positions, it is possible to mount the substrate 32 for mounting an electronic component 7 at equal intervals.
More specifically, an example in which the calculation of the correction amount in FIG. 2 is applied to the calibration substrate 1 will be described. FIG. 3A is a plan view showing an example of the pattern of the calibration substrate 1 in the embodiment of the present invention. The one vertex A ₁ near the square A ₁ B ₁ C ₁ D ₁ on the calibration substrate 1, the pattern 40 of spot pattern is formed as an example of an irregular pattern.
First, the guarantee temperature T _1, are simultaneously captured by the first camera 4a and the second camera 4b, respectively, as the vertices A ₁ near the image is observed as shown in Figure 3B and 3C. In FIG. 3B, the image processing apparatus 5 calculates the center of gravity position of the pattern of the region 43 surrounded by the solid line frame 41 in FIG. 3B as A _1a . Here, the region 43 surrounded by the frame 41 is a region including the center of gravity position A _1a which is an example of the mounting position corresponding portion.
Next, in FIG. 3C, a spotted pattern equivalent to the spotted pattern in the region 43 surrounded by the solid line frame 41 in FIG. _1b is calculated by the image processing apparatus 5. When the calibration substrate 1 itself is deformed by heating or suction fixation at the mounting temperature T ₂ , these patterns are also deformed following the deformation of the calibration substrate 1 itself.
Next, the mounting temperature T _2, are imaged simultaneously by the first camera 4a and the second camera 4b, respectively, as the vertices A ₁ near the image is observed as in Figure 3D and Figure 3E. Here, the pattern of the region 43 surrounded by the solid frame 41 in FIGS. 3B and 3C moves to the region 43 surrounded by the solid frame 41 in FIGS. 3D and 3E, respectively. The center-of-gravity positions change from A _1a and A _1b to A _2a and A _2b , respectively. Although the two first and second cameras 4a and 4b appear to be displaced in different directions, the coordinates of the centroid positions A _1a, A _1b, A _2a , A _2b , the first camera 4a and the second camera 4b The absolute coordinates of the vertices A ₁ and A ₂ from the distance between the first camera 4 a and the second camera 4 b toward the calibration substrate 1 and the surface of the stage 2. 5, and the difference is derived by the image processing device 5 as the displacement amount (ΔX, ΔY) of the vertex A _1. Therefore, the displacement amount (position coordinate correction amount) is calculated with high accuracy by the image processing device 5. Can do. Similar to the vertex A ₁ , the image processing device 5 derives the amount of displacement of the coordinates of each vertex (correction amount of the position coordinates) by analyzing all the vertices of the grid on the calibration substrate 1 by the image processing device 5. be able to. In addition, although the case where the digital image correlation method was used with the image processing apparatus 5 was demonstrated, it is not restricted to this method. A general image analysis method may be used in the image processing apparatus 5.
FIG. 4 is a process flow diagram showing a flow of a method for 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 mounting position correction amount in the embodiment of the present invention. FIG. 6A is a schematic configuration diagram illustrating a configuration of the electronic component mounting apparatus according to the embodiment. A mounting correction amount calculation method will be described with reference to FIGS. 1, 4, 5, and 6 </ b> A.
First, in step S1, the calibration substrate 1 stored in a substrate storage unit (not shown) is taken out from the substrate storage unit using a transport jig (not shown) and placed on the stage 2. Here, the 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. For example, a spot-like pattern is formed on the surface of the calibration substrate 1.
Next, in step S2, at time _{t 11} the temperature reached guarantee temperature _{T 1} of the calibration substrate 1, the first camera 4a and the second camera 4b Calibration substrate 1 as a whole image _C 11A _{using, C 11B} At the same time. Here, guaranteed temperatures _{T 1} is, for example, 25 ° C..
Then, in step S3, after heating the stage 2 to at least the mounting temperature T _2, the calibration substrate 1 is adsorbed to the stage 2 by ON the vacuum suction device 10 connected to a number of suction grooves 2a of the stage 2 The calibration substrate 1 is fixed to the stage 2.
Then, in step S4, the time calibration substrate temperature became mounting temperature _{T 2 t 21,} the first camera 4a and the second camera 4b Calibration substrate 1 as a whole image _C 21A with _{a C 21B} simultaneously imaging To do. Data of the images captured in steps S2 and S4 are taken into the image processing apparatus 5. Each image captured simultaneously by the first camera 4a and the second camera 4b may include at least an image of a region including 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.
Thereafter, when the same processes as those in step S3 and step S4 are repeated, in step S8, the calibration substrate 1 stored in the substrate storage unit is taken out from the substrate storage unit using a transport jig in the same manner as in step S1. After mounting on the stage 2, steps S3 to S5 are performed. For example, when step S3 and step S4 are performed twice, the images C _22A , C _22B, C _23A , and the entire image C _22A , C _22A , the entire calibration substrate 1 are used at the times t _{22 and} t ₂₃ using the first camera 4a and the second camera 4b. After C _23B is imaged simultaneously, they are taken into the image processing device 5. Here, mounting temperature _{T 2} is, for example, 0.99 ° C..
In step S6, using the image processing unit 5, and converts the image _{C 11A} and _{C 11B,} the image _{C 21A} and _{C 21bL,} image _{C 22A} and _{C 22B,} the image _{C 23A} and _{C 23B} to the vertex coordinates of the grid 42 Thereafter, based on the above-described calculation method of the center of gravity position, the position coordinates (X _1Gi , Y _1Gi ) of the mounting position corresponding portion at the guaranteed temperature T ₁ and time t ₁₁ , the mounting temperature T ₂ and time t _21, t _22, t _23, the position coordinates (X 2 _{Gi 1} , Y 2 _{Gi 1} ), (X 2 _{Gi 2} , Y 2 _{Gi 2} ), and (X 2 _{Gi 3} , Y 2 _{Gi 3} ) of the mounting position corresponding portion are derived by the image processing device 5. Further, in the image processing apparatus 5, the position coordinates of mounting positions corresponding portion _{(X 2Gi1, Y 2Gi1),} (X 2Gi2, Y 2Gi2), mounting position in the mounting temperature _{T 2} by averaging the _{(X 2Gi3, Y} 2Gi3) The position coordinates (X _2Gi , Y _2Gi ) of the corresponding location are assumed.
Further, in step S7, pull mounting temperature _T coordinates of the mounting position corresponding positions in _{2 (X 2Gi, Y} 2Gi) from the position coordinates _{(X 1Gi, Y} 1Gi) mounting position corresponding location in the guarantee temperature _{T 1} of a mounting A position correction amount (Δxi, Δyi) for each position corresponding position is calculated by the image processing device 5.
The above is the method for deriving the position correction amount by the image processing device 5.
In the embodiment described above, once the guarantee temperature T _1, although the mounting temperature T ₂ in three cases not limited thereto. For once even at mounting temperature T _2, it is possible to derive the position correction amount in a short time.
Further, by repeating the suction and removal of the calibration substrate 1 and increasing the number of times of image capture, there is an effect of further improving the position correction accuracy. Moreover, although the calibration board | substrate 1 used the board | substrate storage unit and described the method of adsorb | sucking the calibration board | substrate 1 with a conveyance jig, it is not restricted to this. The same effect can be obtained by manually detaching the calibration substrate 1 from the stage 2 and placing it on the stage 2.
When the mounting board 32 is heated, not only the mounting board 32 is warped, but also when the mounting board 32 is sucked to the stage 2 in the mounting process, there is a variation in the sucking position. Variations in deformation. By repeatedly sucking and removing the calibration substrate 1 and capturing images a plurality of times, it is possible to calculate an average value that takes into account variations in the positions corresponding to the mounting positions, and the position correction accuracy is further improved.
In addition, when the guaranteed temperature T ₁ or the mounting temperature T ₂ is high, air near the calibration board is heated by radiant heat, resulting in air temperature variations, and when the camera 4 captures an image, the air looks like a flame. The fluctuation image is distorted. In such a case, images may be captured and averaged multiple times. If comprised in this way, even if the calibration board | substrate 1 is high temperature, a high position correction precision can be ensured.


Next, a method for mounting an electronic component on the mounting board 32 using the position correction amount derivation method will be described. At the time of mounting, coordinates (x _i , y _i ) obtained by adding the position correction amounts (Δx _i , Δy _i ) obtained by the image processing device 5 by the above-described method to the design coordinates (x _i , y _i ) of each mounting position at the mounting temperature T _{2. i} + _{Δx i,} by implementing a position of _{y i} + _{Δy i),} when returning to guarantee temperature _{T 1,} the coordinates of each mounting position becomes _(x i, _{y i).}
As an example, a description will be given based on a specific embodiment. When a semiconductor element as an electronic component 7 is mounted on a circular mounting substrate 32 made of glass having an outer dimension of 300 mm in diameter, a thickness of 0.7 mm, and a linear expansion coefficient of 8 ppm / ° C. [ie, μm / ° C./m]. Will be described. The semiconductor element has a size of 10 mm × 10 mm and a thickness of 0.3 mm, and the mounting pitch interval between the designed semiconductor elements is 15 mm. 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 is changed to the suction OFF state at stage 2 at 30 ° C. and the stage 2 at 150 ° C. Images were taken at the same time in the suction ON state. As a result of image analysis by the image processing apparatus 5, it was found that a positional shift of 130 to 160 μm at maximum occurs at 30 ° C. and 150 ° C. The position correction amount at the mounting position of 15 mm pitch is obtained by the image processing apparatus 5 by image processing, and the mounting substrate 32 that is maintained at 150 ° C. by heating or cooling is mounted on the mounting position that is the position where the position correction amount is added. Mounting was performed with a mounting device.
Thereafter, the mounting substrate 32 was removed from the stage 2, and the amount of positional deviation from the design value of the mounting position of the electronic component was measured at 30 ° C. using a measuring microscope. As a result, it was confirmed that the mounting position deviation amount was within ± 3 μm in the x and y directions with respect to 200 mounting positions. Further, one image at 30 ° C., three images at 150 ° C., and two first and second cameras 4a and 4b were simultaneously captured, but the images could be captured in a short time of 10 ms per image.
In the above embodiment, the case where the camera 4 is configured by the two cameras 4a and 4b has been described. However, the present invention is not limited to this. Three or more cameras 4 may be used. For example, FIG. 6B is a schematic configuration diagram illustrating a configuration of an electronic component mounting apparatus according to a 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, camera first to third cameras 4a, 4b, and 4c. The obstacle 6 is composed of, for example, a pillar or a partition. The point Gia, which is one example of the mounting position corresponding portion on the calibration board 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 board 1, is blocked by the obstacle 6 and cannot be imaged from the first camera 4a, but from the position of the second camera 4b and the third camera 4c. Images can be taken simultaneously. By compensating the area that cannot be captured 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 board 1 can be calculated. It becomes possible to mount with accuracy. In particular, there is an effect that can be applied to a larger mounting substrate 32 than in the case of the mounting apparatus of FIG.
As described above, according to the embodiment of the present invention, when mounting the electronic component 7 while heating the mounting substrate 32, the positional deviation error is greatly reduced without providing the recognition mark on the mounting substrate 32. Therefore, it is possible to mount on the mounting board 32 with high accuracy by performing position correction (calibration) in a short time.
In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, the irregular pattern is not limited to spots, and may be an irregular pattern such as an arbitrary shape, pattern, or pattern. In the case of an arbitrary irregular pattern, there is an advantage that a mounting position corresponding location can be calculated from any location. Moreover, it is good also as regular patterns, such as arbitrary shapes, patterns, or designs, instead of an irregular pattern.
In addition, it can be made to show the effect which each has by combining arbitrary embodiment or modification of the said various embodiment or modification suitably. In addition, combinations of the embodiments, combinations of the examples, or combinations of the embodiments and examples are possible, and combinations of features in different embodiments or examples are also possible.

  The electronic component mounting method and mounting apparatus according to the above aspect of the present invention have the effect that the electronic component can be mounted with very high accuracy while heating the substrate, and calibration can be performed in a short time. This is particularly useful in a mounting method and mounting apparatus for a semiconductor element such as a large-capacity memory, an application processor, a CPU, or a high-frequency communication module.

DESCRIPTION OF SYMBOLS 1,101 Calibration substrate 2 Stage 2a Suction groove 3, 103 Mounting head 4, 4a, 4b, 4c, 104 Camera 5 Image processing device 6 Obstacle 7 Electronic component 8 Drive mechanism 10 Vacuum suction device 31 Electronic component supply unit 32 Mounting substrate 40 Spot pattern 41 Frame 42 Lattice 43 Region 102 Substrate transport unit 105 Component supply unit 106 X drive shaft 107 Y drive shaft

Claims (3)

Calculate the correction data for the mounting position of the electronic component using the calibration board,
At the mounting position based on the correction data, the electronic component is mounted on a mounting substrate heated to a mounting temperature,
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
Adsorb the calibration substrate on the stage,
Simultaneously capturing an image of a region including at least the same mounting position corresponding portion of the calibration board by a plurality of cameras,
Electronic component mounting method obtained by calculating a correction amount of the mounting position from a plurality of images simultaneously captured by the plurality of cameras based on information on the mounting position corresponding portion in the region .   After adsorbing the calibration substrate, the images are simultaneously captured by the plurality of cameras, and after the adsorption of the calibration substrate is released and again adsorbed, the images are simultaneously captured by the plurality of cameras. The electronic component mounting method according to claim 1, wherein a correction amount of the mounting position is calculated based on images captured a plurality of times by the plurality of cameras. A mounting head having the function of holding electronic components and mounting them on the mounting position of the mounting board;
A stage provided so as to face the mounting head and capable of adsorbing the mounting substrate and the calibration substrate,
A driving mechanism that moves the mounting head or the stage in a lateral direction that intersects the vertical direction relatively;
The resolution, magnification, and focal length arranged at the same height with respect to the stage so that an image of an area including at least the same mounting position corresponding portion of the calibration board adsorbed to the stage can be simultaneously captured. The same cameras,
An electronic component mounting apparatus comprising:
An image processing apparatus that calculates a correction amount of the mounting position of the electronic component corresponding to the mounting position corresponding location from information on the mounting position corresponding location of a plurality of images simultaneously captured from the plurality of cameras;
An electronic component mounting apparatus that mounts the electronic component held by the mounting head on the mounting position of the mounting substrate attracted to the stage based on the calculated correction amount of the mounting position.

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