Solder bump flattening equipment

Abstract

To provide a solder bump flattening device capable of suppressing variation in the size of solder bumps even when the tops of a plurality of spherical solder bumps are flattened in a wiring substrate having a plurality of regions with different solder bump densities.SOLUTION: A solder bump flattening device 1 includes an indenter 2 that flattens the top of a solder bump 120 by indenting an indentation head 22, a measuring unit 3 that measures the density of the solder bumps in each of a plurality of areas, and a pressing condition setting unit 4 that sets the pressing amount and pressing load of the indentation head with respect to the solder bump according to the measured solder bump density for each of the plurality of areas, and the indenter pushes the indentation head into the top with a set pushing amount and pushing load.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a solder bump planarization apparatus. [Background technology]

[0002] A semiconductor package in which a chip such as an LSI chip is mounted on a wiring board via a plurality of solder bumps is manufactured by forming a plurality of solder bumps on a plurality of pads of the wiring board, respectively, and then bonding a plurality of terminals of the chip to the plurality of solder bumps. The tops of the solder bumps are spherical when formed on the wiring board. Therefore, the height of the solder bumps is likely to vary. As a result, a problem occurs in which some terminals of the chip are not bonded to the solder bumps. Conventionally, to solve this problem, a pressing block with a flat surface is pressed against the tops of multiple solder bumps formed on a wiring board to flatten the tops of the multiple solder bumps and make the heights of the solder bumps uniform (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-112133 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in recent years, with the improvement of the performance of semiconductor packages, the manner in which chips are mounted on wiring boards has become more diverse. For example, multiple chips of different types may be mounted on the same wiring board, or multiple chips having multiple functions may be mounted on the wiring board. For this reason, the pitch and size of the chip terminals may differ for each chip (or for each function of the chip) to be mounted. In this case, the density of the solder bumps (pitch of the solder bumps, diameter dimension and height dimension of the solder bumps) on the wiring board also differs for each region on the wiring board. For example, when the pitch of the terminals of a first chip mounted on a first region of the wiring board is small, the density of the solder bumps on the first region of the wiring board is large. On the other hand, when the pitch of the terminals of a second chip mounted on a second region of the wiring board is large, the density of the solder bumps on the second region of the wiring board is small. However, when there are multiple regions with different solder bump densities on a wiring board, even if all the solder bumps are pressed by a pressing block under the same conditions (same pressing load, same pressing amount) and the tops of the multiple solder bumps are flattened, as in the conventional method, the size of the solder bumps (especially the height and top surface area) will vary, which will lead to a decrease in the yield of wiring boards on which solder bumps are formed.

[0005] In consideration of the above circumstances, the present invention aims to provide a solder bump flattening device that can suppress variation in the size of solder bumps even when flattening the tops of solder bumps on a wiring board having multiple regions with different solder bump densities. [Means for solving the problem]

[0006] The present invention is a solder bump flattening device for flattening the spherical tops of a plurality of solder bumps formed on a wiring board having a plurality of regions with different solder bump densities, the solder bump flattening device comprising: a push-in section including a push-in head for pushing into the tops of the solder bumps and flattening the tops by pushing the push-in head into the tops, a measurement section for measuring the density of the solder bumps in each of the plurality of regions, and a push-in condition setting section for setting a push-in amount and a push-in load of the push-in head against the solder bumps in accordance with the measured density of the solder bumps for each of the plurality of regions. The push-in section pushes the push-in head into the tops of the solder bumps with the set push-in amount and push-in load. Effect of the Invention

[0007] According to the present invention, even if the tops of the solder bumps are flattened in a wiring board having a plurality of regions with different solder bump densities, it is possible to suppress the occurrence of variations in the size of the solder bumps. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing a configuration of a solder bump flattening apparatus according to an embodiment of the present invention; [Diagram 2] 2 is a plan view showing a first example of a wiring board to be handled by the solder bump flattening apparatus of FIG. 1. [Diagram 3] 1. FIG. 4 is a plan view showing a second example of a wiring board to be handled by the solder bump flattening apparatus of FIG. [Figure 4] 2 is a diagram showing a data table of solder bump specification information stored in a first storage unit in FIG. 1; FIG. [Diagram 5] FIG. 2 is a diagram illustrating an example of the configuration of a measurement unit in FIG. [Figure 6] 6 is a diagram for explaining measurement of the amount of warpage of a wiring board by the measurement unit of FIGS. 1 and 5. FIG. [Figure 7] 2 is a diagram showing a data table stored in a second storage unit in FIG. 1; [Figure 8]2 is a diagram showing how the pressing head of the pressing unit in FIG. 1 is pressed into the tops of the solder bumps in each region. [Figure 9] 9 is a diagram showing an example of a solder bump whose top has been flattened by the pressing head of FIGS. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, one embodiment of the present invention will be described with reference to FIGS. The solder bump flattening apparatus 1 according to this embodiment shown in Fig. 1 is an apparatus for flattening the spherical tops of a plurality of solder bumps 120 formed on a wiring substrate 100 having a plurality of regions 131, 132 with different densities of the solder bumps 120 as illustrated in Fig. 2 and 3. First, the wiring substrate 100 (100A, 100B) on which the solder bumps 120 are to be flattened will be described.

[0010] 2 has one first region 131 in which the density of solder bumps 120 is high, and one second region 132 in which the density of solder bumps 120 is lower than that of first region 131. In the wiring board 100A of FIG. 2, the first region 131 and the second region 132 are positioned adjacent to each other along the top surface 110 of the wiring board 100A. In the first region 131, the pitch of the solder bumps 120 is small, so the density of the solder bumps 120 is high. On the other hand, in the second region 132, the pitch of the solder bumps 120 is large compared to the first region 131, so the density of the solder bumps 120 is low. In FIG. 2, the size of the multiple solder bumps 120 is the same regardless of whether they are in the first or second region 131 or 132. If the size (height dimension or diameter dimension) of each solder bump 120 in each region 131 or 132 is large, for example, the density of the solder bumps 120 is high. Conversely, if the size (height dimension or diameter dimension) of each solder bump 120 in each region 131 or 132 is small, for example, the density of the solder bumps 120 is low.

[0011] The wiring board 100B illustrated in FIG. 3 has a first region 131 in which the density of the solder bumps 120 is high, and a second region 132 in which the density of the solder bumps 120 is lower than that of the first region 131, similar to the wiring board 100A illustrated in FIG. 2. However, in the wiring board 100B illustrated in FIG. 3, the second region 132 is formed so as to surround the first region 131. Also, in FIG. 3, the rectangular second region 132 is divided into a plurality of regions (six in FIG. 3) so as not to overlap with the solder bumps 120 in the first region 131. The divided second regions 132 are arranged in the circumferential direction surrounding the first region 131. The number of solder bumps 120 included in the second region 132 may be equal to each other among the plurality of second regions 132 as illustrated in FIG. 3, or may be different from each other. The shapes and sizes of the first region 131 and the second region 132 in FIGS. 2 and 3 correspond to the shape and size (the shape and size of the pressing surface 22a) of the pressing head 22 of the pressing portion 2 shown in FIGS.

[0012] 1, the solder bump flattening apparatus 1 includes a push-in unit 2, a measurement unit 3, and a push-in condition setting unit 4. The solder bump flattening apparatus 1 of this embodiment also includes a first storage unit 5, a data reading unit 6, a display unit 7, and a second storage unit 8. In this embodiment, the push-in condition setting unit 4, the data reading unit 6, and the display unit 7 are included in the same data processing device 10, but this is not limited to this.

[0013] The pressing unit 2 flattens the tops of the solder bumps 120 on the wiring board 100 by pressing the pressing head 22 into the tops of the solder bumps 120 on the wiring board 100 (see FIGS. 8 and 9). The pressing unit 2 has a stage 21, a pressing head 22, a head driving unit 23, and a control unit 24. Stage 21 has a mounting surface 21a on which wiring board 100 is placed. Stage 21 is movable relative to pressing head 22 in a direction along mounting surface 21a (in the direction indicated by arrow D1 in FIG. 1).

[0014] The pressing head 22 is a part that presses into the tops of the solder bumps 120 in order to flatten the tops of the solder bumps 120 (see FIG. 8). The pressing head 22 is disposed above the stage 21 and is movable in the up and down directions relative to the stage 21. The pressing head 22 has a flat pressing surface 22a that faces the mounting surface 21a of the stage 21. The pressing surface 22a is a surface that is pressed against the tops of the solder bumps 120 when the tops of the solder bumps 120 are flattened. The pressing head 22 is pressed against the tops of the solder bumps 120 in a single region 131, 132 (see FIGS. 2 and 3) of the wiring board 100, that is, it is not pressed against the tops of the solder bumps 120 in multiple regions 131, 132 simultaneously.

[0015] The head driving unit 23 drives the pressing head 22 in the vertical direction (the direction indicated by the arrow D2 in FIG. 1). The pressing head 22 is detachable from the head driving unit 23. This allows the pressing unit 2 to select from a plurality of types of pressing heads 22 differing in size and shape (particularly the area and shape of the pressing surface 22a as viewed from the vertical direction). The control unit 24 controls the operation of the stage 21 and the pressing head 22 based on the pressing conditions (pressing amount and pressing load) output from the pressing condition setting unit 4 described later and data of the wiring board 100 (position information indicating the position on the wiring board 100 where the pressing head 22 is pressed).

[0016] The first storage unit 5 stores data on a plurality of types of wiring boards 100. The data on the wiring boards 100 shown in Figures 2 and 3 is an example. The data on the wiring boards 100 includes drawing data including each wiring board 100 and solder bumps 120 formed thereon, as shown in Figures 2 and 3, and position information indicating the positions of a plurality of regions 131, 132 on the wiring board 100. The data for wiring board 100 also includes a data table showing pitches P1, P2 of solder bumps 120 corresponding to each region 131, 132 (position information), target values ​​TH1, TH2 of the height dimension and target values ​​TR1, TR2 of the diameter dimension of solder bump 120 after flattening (hereinafter also referred to as specification information of solder bump 120), as shown in FIG. The data table shown in FIG. 4 corresponds to the data of the wiring boards 100A and 100B shown in FIG. 2 or FIG.

[0017] 1 reads data of the corresponding type of wiring board 100 from first storage unit 5 when an operator operating solder bump flattening apparatus 1 inputs or selects the type (product number) of wiring board 100. Among the read data of wiring board 100, position information of multiple areas 131, 132 is used by measurement unit 3 to measure the density of solder bumps 120 in each of areas 131, 132 and for measurement unit 3 and pressing unit 2 to recognize the positions of each of areas 131, 132 when pressing unit 2 presses pressing head 22 into the tops of solder bumps 120 in each of areas 131, 132. In addition, among the data of the wiring board 100 that has been read out, the specification information of the solder bump 120 corresponding to each of the regions 131, 132 illustrated in FIG. 4 (target values ​​TH1, TH2 of the height dimension of the solder bump 120, and target values ​​TR1, TR2 of the diameter dimension) is used in the pressing condition setting unit 4 to set the pressing conditions (pressing amount and pressing load) of the pressing head 22 against the solder bump 120. The data of wiring board 100 read by data reading unit 6 may be displayed on display unit 7, for example.

[0018] 1 measures the density of the solder bumps 120 in each of the multiple regions 131, 132 before the multiple solder bumps 120 formed on the wiring board 100 are flattened by the pressing unit 2. In this embodiment, the density of the solder bumps 120 in each of the multiple regions 131, 132 is measured based on position information of the multiple regions 131, 132 (see FIGS. 2 and 3) included in the data of the wiring board 100 read from the first storage unit 5 by the data reading unit 6. The measuring unit 3 has a stage 31 for placing the wiring board 100 thereon and a measuring device 32 for measuring the density of the solder bumps 120 in each of the regions 131, 132.

[0019] Stage 31 of measurement unit 3 has a mounting surface 31a on which wiring board 100 is placed, and is movable in a direction along mounting surface 31a (the direction shown by arrow D3 in FIG. 1) relative to measuring device 32. Stage 31 of measurement unit 3 may be shared with stage 21 of pressing unit 2 described above.

[0020] Measuring device 32 is positioned above and spaced from mounting surface 31a of stage 31. Measuring device 32 may be, for example, camera 32C shown in Fig. 5. In this case, for example, in an image of each of regions 131, 132 of wiring board 100 captured by camera 32C, the density of solder bumps 120 in each of regions 131, 132 may be measured based on the ratio of an area where multiple solder bumps 120 are present to an area where they are not present.

[0021] The measuring device 32 of this embodiment measures the pitches P1, P2 of the solder bumps 120, the diameters MR1, MR2 of the solder bumps 120, and the heights MH1, MH2 of the solder bumps 120 in each of the regions 131, 132 as the density of the solder bumps 120 in each of the regions 131, 132. The pitches P1, P2, diameters MR1, MR2, and heights MH1, MH2 of the solder bumps 120 measured by the measuring unit 3 may be average values ​​(or representative values) of the diameters and heights of the multiple solder bumps 120 in the same region 131, 132. In the following description, the measured values ​​of the diameters MR1, MR2 and heights MH1, MH2 of the solder bumps 120 may be referred to as the measured diameters MR1, MR2 and measured heights MH1, MH2 of the solder bumps 120. When the pitches P1, P2 of the solder bumps 120 in each of the regions 131, 132 are included in the specification information of the solder bumps 120 as illustrated in FIG. 4, it is not necessary to measure the pitches P1, P2 of the solder bumps 120 by the measuring instrument 32, for example.

[0022] In this embodiment, a laser length measuring device 32L is used as the measuring device 32. The laser length measuring device 32L irradiates a laser beam toward the wiring board 100 and the solder bumps 120 to be measured, and obtains the reflected light as a height data profile, thereby measuring the height dimensions MH1, MH2 of the solder bumps 120. In addition, the wiring board 100 and the solder bumps 120 to be measured and the laser length measuring device 32L are moved relatively by the stage 31 or the like, thereby measuring the three-dimensional shapes of the wiring board 100 and the solder bumps 120 in each of the regions 131, 132, thereby measuring the pitches P1, P2 of the solder bumps 120, the diameter dimensions MR1, MR2 of the solder bumps 120, and the height dimensions MH1, MH2 of the solder bumps 120 in each of the regions 131, 132. In this case, it is possible to measure with high accuracy the pitches P1, P2 of the solder bumps 120, the diameters MR1, MR2 of the solder bumps 120, and the heights MH1, MH2 of the solder bumps 120. In other words, it is possible to measure with high accuracy the density of the solder bumps 120 in each of the regions 131, 132, compared to the case where the camera 32C is used. The camera 32C of the measuring unit 3 described above may be used to confirm the positions of the solder bumps 120 in each of the regions 131, 132 when performing measurement by the laser length measuring device 32L described above, for example.

[0023] The measuring unit 3 of this embodiment further measures the amount of warping of the wiring board 100 placed on the stage 31 as shown in FIG. 6. The amount of warping of the wiring board 100 may be expressed, for example, by dividing the upper surface 110 of the wiring board 100 into a number of measurement areas arranged in a matrix, and by the height position BH of the upper surface 110 of the wiring board 100 in the number of measurement areas based on the placement surface 31a of the stage 31. In this embodiment, the amount of warping of the wiring board 100 is set for each of the multiple areas 131, 132 by the average value of the height positions BH of the upper surface 110 of the wiring board 100 in the corresponding areas 131, 132. The height position BH of the upper surface 110 of the wiring board 100 (the amount of warping of the wiring board 100) may be measured, for example, by the laser length measuring device 32L described above. In the following description, the measured amount of warping of the wiring board 100 may be referred to as the measured value of the amount of warping. Data of wiring board 100 measured in measuring unit 3 (pitch P1, P2, height dimensions MH1, MH2 and diameter dimensions MR1, MR2 of solder bumps 120, and the amount of warping of wiring board 100) may be displayed, for example, on display unit 7 (see FIG. 1).

[0024] The pressing condition setting unit 4 shown in FIG. 1 sets pressing conditions of the pressing head 22 for the solder bumps 120 according to the density of the solder bumps 120 measured by the measuring unit 3 for each of the multiple regions 131, 132 of the wiring board 100. The pressing conditions of the pressing head 22 include the pressing amount and pressing load of the pressing head 22 for the solder bumps 120. The pressing amount is the length PL by which the pressing head 22 moves downward after the pressing surface 22a of the pressing head 22 comes into contact with the spherical top of the solder bump 120 (see FIG. 8). The pressing load is the magnitude of the force that presses the pressing head 22 into the top of the solder bump 120. For example, when the density of the solder bumps 120 in the predetermined regions 131, 132 is high, the pressing condition setting unit 4 sets the pressing load to be large, and when the density of the solder bumps 120 is low, the pressing load to be small.

[0025] In this embodiment, the pressing condition setting unit 4 sets the pressing amount and pressing load of the pressing head 22 for each of the multiple regions 131, 132 according to the pitches P1, P2 of the solder bumps 120, the diameter dimensions MR1, MR2 of the solder bumps 120, and the height dimensions MH1, MH2 of the solder bumps 120 (see FIG. 5) measured as the density of the solder bumps 120 by the measuring unit 3. Note that, in setting the pressing amount and pressing load of the pressing head 22, the pitches P1, P2 of the solder bumps 120 included in the specification information of the solder bumps 120 illustrated in FIG. 4 may be used instead of the pitches P1, P2 of the solder bumps 120 measured by the measuring unit 3.

[0026] For example, the larger the pitches P1, P2 of the solder bumps 120 in the predetermined regions 131, 132, the greater the density of the solder bumps 120, and the greater the pressing load is set by the pressing condition setting unit 4. The larger the difference between the measured values ​​MR1, MR2 of the diameter of the solder bumps 120 and the target values ​​TR1, TR2 of the diameter of the solder bumps 120, the greater the pressing load is set by the pressing condition setting unit 4. The larger the difference between the measured values ​​MH1, MH2 of the height of the solder bumps 120 in the predetermined regions 131, 132 and the target values ​​TH1, TH2 of the bump height is set by the pressing condition setting unit 4.

[0027] Furthermore, the pressing condition setting unit 4 of this embodiment sets the pressing amount and pressing load of the pressing head 22 according to the amount of warping of the wiring board 100 measured by the measurement unit 3. For example, the pressing condition setting unit 4 sets a larger pressing amount and pressing load as the amount of warping of the wiring board 100 in the predetermined areas 131, 132 (height position BH of the upper surface 110 of the wiring board 100) increases. The reason for this is that when the predetermined areas 131, 132 of the wiring board 100 are located above and away from the stage 21 (31) according to the warping of the wiring board 100, the predetermined areas 131, 132 of the wiring board 100 are pressed and moved toward the stage 21 as the pressing head 22 presses the areas 131, 132.

[0028] The pressing condition setting unit 4 may derive the pressing amount and pressing load of the pressing head 22 by performing calculations based on, for example, specification information of the solder bumps 120 read out from the data reading unit 6 (pitch P1, P2 of the solder bumps 120, target values ​​TH1, TH2 of the height dimension of the solder bumps 120, and target values ​​TR1, TR2 of the diameter dimension) and the pitch P1, P2 of the solder bumps 120, measured values ​​MH1, MH2 of the height dimension, and measured values ​​MR1, MR2 of the diameter dimension, and the measured value of the warpage of the wiring board 100 measured by the measuring unit 3. In this embodiment, the pressing condition setting unit 4 reads out and sets the pressing amount and pressing load of the pressing head 22 corresponding to the pitch P1, P2 of the solder bumps 120, the target values ​​TH1, TH2 and target values ​​TR1, TR2 of the height dimension of the solder bumps 120, the measured values ​​MH1, MH2 and MR1, MR2 of the height dimension of the solder bumps 120, and the measured amount of warping of the wiring board 100 from a data table shown in FIG. 7 which is previously stored in the second memory unit 8.

[0029] The second storage unit 8 stores a data table shown in FIG. The data table includes a correspondence table 81. In the correspondence table 81, the difference ΔH between the measured values ​​MH1, MH2 of the height dimension of the solder bump 120 and the target values ​​TH1, TH2, and the difference ΔR between the measured values ​​MR1, MR2 of the diameter dimension of the solder bump 120 and the target values ​​TR1, TR2 are associated with the indentation conditions Aij (i, j are integers equal to or greater than 1) of the indentation head 22 including data on the indentation amount and indentation load. In this correspondence table 81, the larger the difference ΔH in the height dimension (the larger the number after ΔH in FIG. 7), the larger the indentation amount of the indentation condition Aij. Also, the larger the difference ΔR in the diameter dimension (the larger the number after ΔR in FIG. 7), the larger the indentation load of the indentation condition Aij. This correspondence table 81 is prepared for each data 82 (hereinafter referred to as bump measurement value data 82) of the measured height dimensions MH1, MH2 and the measured diameter dimensions MR1, MR2 of the solder bump 120. In other words, if the measured height dimensions and diameter dimensions MH1, MH2, MR1, MR2 of the solder bump 120 change, the correspondence table 81 to be referenced also changes.

[0030] Furthermore, multiple bump measurement value data 82 are prepared for each data 83 (hereinafter referred to as bump pitch data 83) of the pitches P1, P2 of the solder bumps 120. That is, if the pitches P1, P2 of the solder bumps 120 change, the bump measurement value data 82 to be referenced also changes. By utilizing the above-mentioned multiple bump pitch data 83, the multiple bump measurement value data 82 contained in each bump pitch data 83, and the correspondence table 81 contained in each bump measurement value data 82, the pressing amount and pressing load of the pressing head 22 can be easily set according to the density of the solder bumps 120 in each region 131, 132.

[0031] Furthermore, in the data table stored in second storage unit 8, a plurality of bump pitch data 83 are prepared for each of data 84 of the measured value of the amount of warpage of wiring board 100 (hereinafter referred to as warpage amount data 84). That is, if the amount of warpage of wiring board 100 changes, the bump pitch data 83 to be referenced also changes. This makes it possible to easily set the pressing amount and pressing load of pressing head 22, taking into account the amount of warpage of wiring board 100 in each of regions 131, 132.

[0032] When utilizing the data table of Figure 7, the pressing condition setting unit 4 first selects, from among the multiple warpage amount data 84 in the data table, the warpage amount data 84 that corresponds to the measured value of the warpage amount of the wiring board 100 output from the measurement unit 3. Next, the pressing condition setting unit 4 selects the bump pitch data 83 corresponding to the pitches P1, P2 of the solder bumps 120 output from the data reading unit 6 (first memory unit 5) or the measurement unit 3 from among the multiple bump pitch data 83 contained in the warpage amount data 84 selected above.

[0033] Then, the pressing condition setting unit 4 selects the bump measurement value data 82 from the multiple bump measurement value data 82 contained in the bump pitch data 83 selected above that corresponds to the measurement values ​​MH1, MH2, MR1, and MR2 of the height and diameter dimensions of the solder bump 120 output from the measurement unit 3. Furthermore, the pushing condition setting unit 4 calculates a difference ΔH in the height dimension of the solder bump 120 and a difference ΔR in the diameter dimension of the solder bump 120 based on the target values ​​TH1, TH2 of the height dimension and the target values ​​TR1, TR2 of the diameter dimension of the solder bump 120 output from the data reading unit 6, and the measured values ​​MH1, MH2 of the height dimension and the measured values ​​MR1, MR2 of the diameter dimension of the solder bump 120 output from the measuring unit 3.

[0034] Then, the pressing condition setting unit 4 refers to the correspondence table 81 included in the bump measurement value data 82 selected as described above, and reads out the pressing conditions Aij of the pressing head 22 including data on the pressing amount and pressing load corresponding to the calculated difference ΔH in the height dimension of the solder bump 120 and the difference ΔR in the diameter dimension of the solder bump 120. In this manner, the pressing amount and pressing load of the pressing head 22 can be easily set.

[0035] 8, the pushing unit 2 pushes the pushing head 22 into the top of the solder bump 120 with a pushing amount and a pushing load set for each of the regions 131, 132 having different densities of the solder bump 120 in the above-mentioned pushing condition setting unit 4, taking into consideration the density of the solder bump 120 and the amount of warping of the wiring board 100. In addition, the pushing unit 2 pushes the pushing head 22 into the top of the solder bump 120 in each of the multiple regions 131, 132, based on the position information of the multiple regions 131, 132 included in the data of the wiring board 100 read by the data reading unit 6 (see FIGS. 2 and 3).

[0036] Specifically, based on position information of regions 131, 132 included in data of wiring board 100 (see FIGS. 2 and 3), control unit 24 (see FIG. 1) of pressing unit 2 moves stage 21 of pressing unit 2 in a direction along its mounting surface 21a, thereby positioning predetermined regions 131, 132 of wiring board 100 mounted on stage 21 directly under pressing head 22. Then, control unit 24 controls the operation of head driving unit 23 of pressing unit 2 based on the pressing amount and pressing load corresponding to predetermined regions 131, 132 output from pressing condition setting unit 4. This allows pressing head 22 to be pressed into the tops of solder bumps 120 arranged in predetermined regions 131, 132 of wiring board 100 with an appropriate pressing amount and pressing load.

[0037] 9 shows an example of the state after the pressing head 22 (see FIG. 8, etc.) has been pressed into the tops of the solder bumps 120 in the regions 131, 132. In this state, the tops of the solder bumps 120 in the regions 131, 132 are formed flat. In the solder bump flattening apparatus 1 of this embodiment, after flattening the tops of the solder bumps 120, the height dimensions AH1, AH2 and diameter dimensions AR1, AR2 of the solder bumps 120 in the regions 131, 132 may be measured by the measuring unit 3 (e.g., laser length measuring device 32L) to check the finish of the flattened solder bumps 120. In addition, the solder bump flattening apparatus 1 may compare, for example, the height dimensions AH1, AH2 and diameter dimensions AR1, AR2 of the solder bump 120 measured after flattening with the target values ​​TH1, TH2 of the height dimension and the target values ​​TR1, TR2 of the diameter dimension of the solder bump 120. In addition, if the measured height dimensions AH1, AH2 and diameter dimensions AR1, AR2 of the solder bump 120 differ from the target values ​​TH1, TH2 of the height dimension and the target values ​​TR1, TR2 of the diameter dimension of the solder bump 120, the solder bump 120 may be pressed again based on these differences.

[0038] 2 includes one each of a first region 131 and a second region 132 having different densities of the solder bumps 120. Therefore, the pressing unit 2 may press the solder bumps 120 into one first region 131 and one second region 132, respectively. 3 includes one first region 131 and multiple second regions 132. Therefore, the pressing unit 2 may press the solder bumps 120 into the one first region 131 and the multiple second regions 132, respectively.

[0039] As described above, the solder bump flattening apparatus 1 of the present embodiment includes the measuring unit 3 that measures the density of the solder bumps 120 in each of the multiple regions 131, 132 of the wiring board 100, and the pressing condition setting unit 4 that sets the pressing amount and pressing load of the pressing head 22 with respect to the solder bumps 120 in accordance with the density of the solder bumps 120 measured in each of the multiple regions 131, 132. The pressing unit 2 presses the pressing head 22 into the top of the solder bumps 120 with the pressing amount and pressing load that are respectively set in accordance with the multiple regions 131, 132 of the wiring board 100 having different densities of the solder bumps 120. In other words, the pressing amount and pressing load of the pressing head 22 with respect to the solder bumps 120 can be set in accordance with the multiple regions 131, 132 of the wiring board 100 having different densities of the solder bumps 120. This makes it possible to suppress variations in size (diameter and height) of solder bumps 120 in each of regions 131 and 132 of planarized wiring substrate 100. By suppressing the variation in size of planarized solder bumps 120 in this manner, it becomes possible to suppress a decrease in the yield of wiring substrate 100 on which solder bumps 120 are formed.

[0040] Furthermore, in the solder bump flattening apparatus 1 of this embodiment, the measuring unit 3 measures the pitches P1, P2 of the solder bumps 120, the diameters MR1, MR2 of the solder bumps 120, and the heights MH1, MH2 of the solder bumps 120 in each of the multiple regions 131, 132 as the density of the solder bumps 120 in each of the multiple regions 131, 132 of the wiring substrate 100. Furthermore, the pressing condition setting unit 4 sets the pressing amount and pressing load of the pressing head 22 in accordance with the pitches P1, P2 of the solder bumps 120, the diameters MR1, MR2, and the heights MH1, MH2 of the solder bumps 120 measured by the measuring unit 3 for each of the multiple regions 131, 132. By referring to the measured pitches P1, P2, diameters MR1, MR2, and heights MH1, MH2 of the solder bumps 120 as the density of the solder bumps 120 in each of the regions 131, 132, it is possible to set with higher precision the pressing amount and pressing load of the pressing head 22. This makes it possible to further uniformize the sizes (diameter and height) of the solder bumps 120 in each of the regions 131, 132 of the wiring substrate 100 after planarization.

[0041] Furthermore, in the solder bump flattening apparatus 1 of this embodiment, the measuring unit 3 includes a laser length measuring device 32L as a measuring device 32 that measures the pitches P1, P2 of the solder bumps 120, the diameters MR1, MR2, and the heights MH1, MH2 of the solder bumps 120 in each of the regions 131, 132. This makes it possible to measure the pitches P1, P2 of the solder bumps 120, the diameters MR1, MR2, and the heights MH1, MH2 of the solder bumps 120 with higher accuracy. Therefore, the indentation amount and indentation load of the indentation head 22 can be set with even higher accuracy.

[0042] In the solder bump flattening apparatus 1 of this embodiment, the measuring unit 3 measures the amount of warping of the wiring substrate 100. The pressing condition setting unit 4 sets the pressing amount and pressing load of the pressing head 22 according to the measured amount of warping. This makes it possible to suppress variations in size (diameter and height) of the solder bumps 120 in the regions 131, 132 of the wiring substrate 100 after the solder bumps 120 are flattened, which are caused by the warping of the wiring substrate 100.

[0043] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and can be modified as appropriate without departing from the spirit of the present invention.

[0044] In the solder bump flattening apparatus of the present invention, the data of wiring board 100 stored in first storage unit 5 may include, for example, only drawing data including wiring board 100 and solder bumps 120. In this case, an operator may manually input specification information of solder bump 120 (position information indicating a plurality of regions 131, 132 on wiring board 100, target values ​​TH1, TH2 of the height dimension of solder bump 120, and target values ​​TR1, TR2 of the diameter dimension) to data reading unit 6 in accordance with the drawing data read by data reading unit 6.

[0045] In the solder bump flattening apparatus of the present invention, second storage unit 8 may store at least a data table that associates the density of solder bumps 120 with the pressing conditions (pressing amount and pressing load) of pressing head 22. Furthermore, pressing condition setting unit 4 may read out from second storage unit 8 and set the pressing amount and pressing load that correspond to at least the density of solder bumps 120 measured by measuring unit 3. [Explanation of symbols]

[0046] 1. Solder bump flattening equipment 2 Pressing section 3 Measuring part 4 Pressing condition setting section 22 Push-in head 32L Laser length measuring instrument 100 Wiring board 120 Solder Bumps 131 First area 132 Second area P1, P2 Pitch of solder bump 120 MR1, MR2 Diameter of solder bump 120 MH1, MH2 Height dimension of solder bump 120

Claims

1. 1. A solder bump flattening apparatus for flattening spherical tops of a plurality of solder bumps formed on a wiring substrate having a plurality of regions with different solder bump densities, comprising: a pressing section including a pressing head that presses into the top of the solder bump, and flattens the top by pressing the pressing head into the top; a measurement unit that measures the density of the solder bumps in each of the plurality of regions; a pressing condition setting unit that sets a pressing amount and a pressing load of the pressing head against the solder bumps in accordance with the measured density of the solder bumps for each of the plurality of regions, The pushing unit pushes the pushing head into the top of the solder bump with the set pushing amount and pushing load.

2. the measuring unit measures a pitch of the solder bumps, a diameter dimension of the solder bumps, and a height dimension of the solder bumps in each of the plurality of regions as the density of the solder bumps in each of the plurality of regions; 2. The solder bump flattening apparatus according to claim 1, wherein the pressing condition setting unit sets the pressing amount and the pressing load according to the measured pitch, diameter dimension and height dimension for each of the plurality of regions.

3. 3. The solder bump flattening apparatus according to claim 2, wherein said measuring section includes a laser length measuring device for measuring a pitch, a diameter dimension and a height dimension of said solder bumps.

4. The measurement unit measures the amount of warping of the wiring substrate, 4. The solder bump flattening apparatus according to claim 1, wherein the pressing condition setting unit sets the pressing amount and the pressing load in accordance with the measured amount of warping.

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