Substrate surface height prediction device, mounting device, substrate surface height prediction method, and mounting method

Abstract

To provide a substrate surface height prediction device, a mounting device, a substrate surface height prediction method, and a mounting method, which make it possible to predict the substrate surface height distribution on a mounting stage in advance even if the substrate has thickness unevenness, and to maintain a predetermined distance between a chip component and a substrate when aligning them. [Solution] A substrate surface height prediction device, a mounting device, a substrate surface height prediction method, and a mounting method are provided, which include a first height distribution measurement means for measuring the surface height distribution of a mounting stage, a temporary placement stage that is provided separately from the mounting stage and is capable of suction-holding a substrate, a second height distribution measurement means for measuring the surface height distribution of the temporary placement stage, and a control unit that is connected to the first height distribution measurement means and the second height distribution measurement means and has a function for inputting each measurement data, a calculation function, and a memory function.

Description

[Technical Field]

[0001] The present invention relates to a mounting apparatus for mounting chip components on a substrate, a substrate surface height prediction apparatus and method used therein, and a substrate surface height prediction method used therein. [Background technology]

[0002] There is an increasing demand for higher precision in mounting devices that mount chip components, such as semiconductor chips, on substrates, with submicron accuracy being required for some applications. To meet this demand for higher precision, it is becoming necessary to align the chip components and the substrate while keeping them as close as possible to each other. In other words, after alignment, misalignment that occurs during the process of moving the chip components closer to the substrate can no longer be ignored.

[0003] When a mounting device brings a chip component close to a board, the mounting head holding the chip component is lowered toward the board, but if the lifting position precision is poor, there is a concern that the mounting head holding the chip component may come into contact with the board. On the other hand, if the approach takes a long time, it will have a negative impact on the takt time, which is undesirable.

[0004] For this reason, a method is used in which height information of the board surface is obtained in advance and then the amount of lowering of the mounting head is controlled (for example, Reference 1).

[0005] It is desirable to obtain substrate surface height information each time a chip component is mounted on a substrate, but performing this for each chip component increases the takt time, which is undesirable from the perspective of productivity. Therefore, Cited Document 1 proposes measuring the surface height distribution of the mounting stage that holds the substrate in advance. This method allows the substrate surface height to be determined by adding the thickness of the substrate to the surface height of the mounting stage. This allows the mounting head to be controlled to lower the chip component as close as possible to the substrate without affecting the takt time. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2022 / 014451 Summary of the Invention [Problem to be solved by the invention]

[0007] By measuring the surface height distribution of the mounting stage in advance, the chip components and the board no longer come into contact during alignment, even when the distance between the chip components and the board is set to 0.1 mm (100 μm).However, it was found that there was an error of ±20 μm in the actual measured value for the set value of the distance between the chip components and the board of 100 μm.

[0008] If the distance between the chip component and the board is 100 μm, the chip component will not come into contact with the board even if there is an error of ±20 μm. However, when submicron level mounting precision is required, it has been found that there will be an effect that cannot be ignored.

[0009] In other words, if the optical axis of the imaging means used for alignment is tilted relative to the direction perpendicular to the surface of the board (and chip components), even a slight difference in vertical distance will affect positional accuracy. For example, even if the tilt of the optical axis is 0.3°, a change in height (vertical distance) of 20 μm will cause a position change of 0.1 μm in the in-plane direction, which is not negligible for sub-micron level mounting accuracy.

[0010] Incidentally, even though the surface height distribution of the mounting stage was measured, an error of ±20 μm occurred, which is thought to be due to uneven thickness and deformation of the board.

[0011] The present invention has been made in consideration of the above-mentioned problems, and provides a substrate surface height prediction device, a mounting device, a substrate surface height prediction method, and a mounting method that make it possible to predict the substrate surface height distribution on a mounting stage in advance even if the substrate has thickness unevenness, and to maintain a predetermined distance between the chip component and the substrate when aligning them. [Means for solving the problem]

[0012] In order to solve the above problem, the invention described in claim 1 is: A substrate surface height prediction device that predicts the height distribution of a substrate held by suction on a mounting stage, The substrate surface height prediction device includes a first height distribution measurement means that measures the surface height distribution of the mounting stage, a temporary placement stage that is provided separately from the mounting stage and is capable of suction-holding a substrate, a second height distribution measurement means that measures the surface height distribution of the temporary placement stage, and a control unit that is connected to the first height distribution measurement means and the second height distribution measurement means and has a function of inputting each measurement data, a calculation function, and a memory function.

[0013] The invention described in claim 2 is the substrate surface height prediction device described in claim 1, The second height distribution measuring means also measures the surface height distribution of the substrate held by suction on the temporary placement stage, and the control unit calculates the thickness distribution of the substrate from the surface height distribution of the substrate and the surface height distribution of the mounting stage, in a substrate surface height prediction device.

[0014] The invention described in claim 3 is the substrate surface height prediction device described in claim 2, The control unit stores the surface height distribution of the mounting stage and the thickness distribution of the substrate, and calculates and predicts the height distribution of the substrate held by suction on the stage from the surface height distribution of the mounting stage and the thickness distribution of the substrate.

[0015] The invention described in claim 4 is a mounting head disposed above the mounting stage and connected to the control unit, the mounting apparatus mounting chip components held by the mounting head onto the substrate on the mounting stage, When mounting the chip component on the substrate, the mounting device adjusts the amount of descent of the mounting head in accordance with the substrate surface height directly below the mounting head, which is determined from the substrate surface height distribution predicted by the substrate surface height prediction device described in any one of claims 1 to 3.

[0016] The invention described in claim 5 is the mounting device described in claim 4, The mounting head is a mounting device having a head height measuring means for measuring the height of the surface that holds the chip components.

[0017] The invention described in claim 6 is A substrate surface height prediction method for predicting a surface height distribution of a substrate held by suction on a mounting stage, comprising: The substrate surface height prediction method includes a mounting stage surface height distribution measurement process for measuring the surface height distribution of the mounting stage; a temporary placement stage surface height distribution measurement process for measuring the surface height distribution of a temporary placement stage that is provided separately from the mounting stage and is capable of suction-holding a substrate; a temporary placement substrate surface height distribution measurement process for measuring the surface height distribution of the substrate suction-held by the temporary placement stage; a substrate thickness distribution calculation process for calculating the thickness distribution of the substrate from results obtained by the temporary placement stage surface height distribution measurement process and the temporary placement substrate surface height distribution measurement process; and a substrate surface height distribution calculation process for calculating and predicting the surface height distribution of the substrate suction-held by the stage using the surface height distribution of the mounting stage obtained in the mounting stage surface height distribution measurement process and the thickness distribution of the substrate calculated in the substrate thickness prediction process.

[0018] The invention described in claim 7 is the substrate surface height prediction method described in claim 6, The substrate surface height prediction method further includes a substrate placement measurement step for determining the placement of the substrate within the mounting stage surface between the temporary-placement substrate surface height distribution measurement step and the substrate surface height distribution calculation step.

[0019] The invention described in claim 8 is A mounting method for mounting chip components on the substrate held by the mounting stage by suction, comprising: In the process of bringing the chip component close to the surface of the substrate, A mounting method for predicting the distance between the chip component and the substrate surface using the surface height distribution of the substrate obtained by the substrate surface height prediction method according to claim 6 or 7. [Effects of the Invention]

[0020] The present invention makes it possible to predict the height distribution of the substrate surface on the mounting stage in advance, even if the substrate has thickness variations. This reduces the variation in the distance between the chip component and the substrate when aligning them, and reduces measurement errors caused by the variation in distance during alignment. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic diagram of a mounting apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing a control system of the mounting apparatus according to the embodiment of the present invention. [Figure 3] 3 is a flowchart of a method for predicting a substrate surface height according to an embodiment of the present invention. [Figure 4] 10A and 10B are diagrams illustrating how the surface heights of the temporary placement stage and the mounting stage are measured by the mounting apparatus according to the embodiment of the present invention. [Figure 5] 1A and 1B are diagrams illustrating a process for measuring the distribution of the surface height of the temporary placement stage in an embodiment of the present invention, in which FIG. 1A shows how the surface height of the temporary placement stage is measured, and FIG. 1B shows an example of a location where the surface height of the temporary placement stage is measured. [Figure 6] 1A and 1B are diagrams illustrating a process for measuring the distribution of the surface height of a mounting stage in an embodiment of the present invention, in which FIG. 1A shows how the surface height of the mounting stage is measured, and FIG. 1B is a diagram illustrating an example of a location where the surface height of the mounting stage is measured. [Figure 7] 10A and 10B are diagrams showing how the mounting apparatus according to the embodiment of the present invention measures the surface height of a temporary placement stage that holds a substrate by suction. [Figure 8]1A and 1B are diagrams illustrating a process for measuring the surface height distribution of a temporary substrate in an embodiment of the present invention, in which FIG. 1A shows how the surface height of a substrate held by suction on a temporary substrate is measured, and FIG. 1B shows an example of a location where the surface height of a substrate held by suction on a temporary substrate is measured. [Figure 9] FIG. 2 is a diagram showing a cross-sectional shape of a substrate. [Figure 10] FIG. 10 is a diagram showing a state in which the substrate is removed from the temporary placement stage in the mounting apparatus according to the embodiment of the present invention. [Figure 11] FIG. 10 is a diagram showing a state in which a substrate is transported to the mounting stage side in the mounting apparatus according to the embodiment of the present invention. [Figure 12] FIG. 10 is a diagram showing a state in which the mounting stage suction-holds a substrate in the mounting apparatus according to the embodiment of the present invention. [Figure 13] 1A and 1B are cross-sectional views showing how a substrate is adsorbed and held on a mounting stage in an embodiment of the present invention, in which (a) is a cross-sectional view of the mounting stage, (b) is a cross-sectional view of the substrate before it is adsorbed and held on the mounting stage, and (c) is a cross-sectional view of the substrate after it has been adsorbed and held on the mounting stage. [Figure 14] FIG. 10 is a schematic diagram of a mounting device according to a modified example of the embodiment of the present invention. [Figure 15] FIG. 10 is a block diagram showing a control system of a mounting apparatus according to a modified example of the embodiment of the present invention. [Figure 16] FIG. 10 is a diagram showing a state in which position information of a substrate on a temporary placement stage is being acquired in a mounting apparatus according to a modified example of an embodiment of the present invention. [Figure 17] 10A and 10B are diagrams illustrating a coordinate system of the temporary placement stage and a coordinate system of the substrate according to a modified example of the embodiment of the present invention, and are a diagram illustrating a coordinate system of the temporary placement stage and a coordinate system of the substrate. [Figure 18] FIG. 10 is a diagram showing a state in which substrate position information on a mounting stage is being acquired in a mounting apparatus according to a modified example of an embodiment of the present invention; [Figure 19]1A and 1B are diagrams illustrating a coordinate system of a mounting stage and a substrate according to a modified embodiment of the present invention, in which FIG. 1A is a diagram illustrating a coordinate system of a substrate, FIG. 1B is a diagram illustrating a coordinate system of a substrate on a mounting stage, and FIG. 1C is a diagram illustrating position information of a substrate on a mounting stage in the coordinate system of the mounting stage. DETAILED DESCRIPTION OF THE INVENTION

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a schematic diagram of a mounting apparatus 1 according to an embodiment of the present invention.

[0023] The mounting apparatus 1 mounts chip components C, such as semiconductor chips, on a substrate S, such as a wiring board. There are two ways of mounting the chip components C on the substrate S: face-up mounting, in which the electrode surfaces of the chip components C and the substrate S face in the same direction, and face-down mounting, in which the electrode surfaces of the chip components C and the substrate S face each other. The mounting apparatus 1 shown in FIG. 1 can be either way.

[0024] The mounting device 1 includes, as its components, a mounting stage 2, an elevating means 3, a mounting head 4, a temporary placement stage 5, a height distribution measuring means 60 (second height distribution measuring means), a height distribution measuring means 61 (first height distribution measuring means), and a substrate transport means 8. In Fig. 1, both the mounting stage 2 and the temporary placement stage 5 are mounted on a base 100, but the substrate stage 2 and the temporary placement stage 5 may also be mounted on separate bases.

[0025] The mounting stage 2, the temporary placement stage 5, the height distribution measuring means 60 (second height distribution measuring means), and the height distribution measuring means 61 (first height distribution measuring means) constitute a substrate surface height prediction device.

[0026] In the mounting device 1, the mounting stage 2 is composed of an X-direction movement means 21, a Y-direction movement means 22, and an adsorption table 23. The adsorption table 23 adsorbs and holds the substrate S placed on its surface, the Y-direction movement means 22 has a function of linearly moving the adsorption table 23 in the Y direction, and the X-direction movement means 21 has a function of linearly moving the Y-direction stage 22 in the X direction relative to the base 100.

[0027] The lifting means 3 is fixed to a frame (not shown), and has a vertical drive shaft that is provided perpendicular to the suction table 23, and the mounting head 4 is connected to the vertical drive shaft. The lifting means 3 has the function of driving the mounting head 4 up and down, and the function of applying a pressure according to a setting.

[0028] The mounting head 4 holds the chip component C and presses it in parallel with the substrate (held on the suction table 23 of the mounting stage 2). Although not shown in Fig. 1, when the mounting head 4 holds the chip component C, it does so via a detachable attachment tool, and the attachment tool is prepared in a shape according to the size of the chip component C.

[0029] The temporary placement stage 5 adsorbs and holds the substrate S placed on its surface, and the substrate S is placed on the temporary placement stage 5 prior to the mounting stage 2. Although the temporary placement stage 5 is shown in a fixed form in FIG. 1, it may also be configured to have an adsorption table that is movable in the X and Y directions, similar to the mounting stage 2.

[0030] The second height distribution measurement means is height distribution measurement means 60, which has a height sensor that measures the surface height. The height sensor is preferably one that is capable of non-contact measurement and has high accuracy, and in this embodiment, a confocal sensor is used.

[0031] The height distribution measuring means 60 is capable of measuring the surface height distribution of the temporary placement stage 5 and the surface height distribution of the substrate S adsorbed and held on the temporary placement stage 5, and measures the surface height distribution of the temporary placement stage 5 or the surface height distribution of the substrate S adsorbed and held on the temporary placement stage 5 while moving the height sensor and the temporary placement stage relatively in the X and Y directions. For this reason, if the temporary placement stage 5 has a configuration including an adsorption table that is movable in the X and Y directions, measurements can be made with the height sensor fixed.

[0032] The height distribution measuring means 61, which is the first height distribution measuring means, is capable of measuring the surface height distribution of the mounting stage 2 (its suction table 23) and the surface height distribution of the substrate S suction-held on the suction table 23, and measures the surface height distribution of the suction table 23 or the surface height distribution of the substrate S suction-held on the suction table 23 while moving the height sensor and the suction table 23 relatively in the X and Y directions. For this reason, when the suction table 23 is moved in the X and Y directions, measurements can be made with the height sensor fixed.

[0033] If the moving range of the height sensor constituting the height distribution measuring means 60 in the XY plane is wide and includes the area covering the mounting stage 2, the height distribution measuring means 60 may also function as the height distribution measuring means 61.

[0034] The substrate transport means 8 has at least the function of transporting the substrate S detached from the temporary placement stage 5 and placing it on the mounting stage 2 (on the suction table 23 thereof). The substrate transport means 8 transports the substrate S by moving a detachable substrate holder 81 for the substrate S along a transport rail 80. The substrate transport means 8 may also have the function of transporting the substrate S taken out from a substrate rack (not shown) to the temporary placement stage 5, and the function of transporting the substrate S on which the mounting of chip components C has been completed from the substrate stage 2 to a subsequent process.

[0035] As shown in the block diagram of Figure 2, the mounting device 1 is equipped with a control unit 10 connected to a substrate stage 2, a lifting means 3, a mounting head 4, a temporary placement stage 5, a height distribution measuring means 60, a height distribution measuring means 61, and a substrate transport means 8.

[0036] The control unit 10 essentially consists of a CPU and a storage device as its main components, and is connected to each unit via an interface as necessary. The control unit 10 also has a built-in program, which allows it to perform calculations using acquired data and output the results of the calculations. It is also desirable for the control unit 10 to have the function of storing acquired data and calculation results and using them as new calculation data.

[0037] The control unit 10 is connected to the substrate stage 2, and controls the operation of the X-direction movement means 21 and the Y-direction movement means 22 to control the in-plane movement of the suction table 23. The control unit 10 also controls the suction table 23 to control the suction holding and release of the substrate S.

[0038] The substrate surface height prediction device 11 is made up of the mounting stage 2, temporary placement stage 5, height distribution measuring means 60 (second height distribution measuring means), height distribution measuring means 61 (first height distribution measuring means), and control unit 10, which are enclosed by the dotted line in Figure 2.

[0039] The control unit 10 is connected to the lifting means 3 and has the function of controlling the position of the mounting head 4 in the vertical direction (Z direction) and also controlling the pressure applied when the chip component C is pressure-bonded to the substrate S.

[0040] The control unit 10 is connected to the mounting head 4, and controls the suction, holding and release of the chip components C, and also controls the heating temperature if a heater is built in.

[0041] The control unit 10 is connected to the temporary placement stage 5 and controls the suction holding and release of the substrate S. In addition, in the case of a configuration having a suction table that is movable in the X and Y directions, the control unit 10 controls the in-plane movement of the suction table.

[0042] The control unit 10 is connected to the height distribution measuring means 60, and has the function of measuring the in-plane height distribution of the upper surface of the temporary placement stage 5 and storing the measurement data by moving the height sensor and the temporary placement stage 5 relatively. In addition, when the temporary placement stage 5 is holding the substrate S by suction, the control unit 10 has the function of measuring the in-plane height distribution of the upper surface of the substrate S held by suction and storing the measurement data.

[0043] The control unit 10 is connected to the height distribution measuring means 61 and has the function of measuring the in-plane height distribution of the upper surface of the suction table 23 and storing the measurement data by moving the height sensor and the suction table 23 relatively. In addition, when the suction table 23 is suction-holding the substrate S, the control unit 10 has the function of measuring the in-plane height distribution of the upper surface of the suction-held substrate S and storing the measurement data.

[0044] The control unit 10 is connected to the substrate transport means 8 and controls the substrate holder 81 to hold and release the substrate S, and also controls the movement of the substrate holder 81.

[0045] The operation of the mounting device 1 shown in FIG. 1 will be explained below. However, as mentioned above, the present invention aims to predict the substrate surface height distribution on the mounting stage 2 (the suction table 23 thereof) in advance, so the process of predicting the substrate surface height distribution on the mounting stage will be mainly explained, rather than the mounting process itself.

[0046] 3 is a flowchart showing the process of data acquisition and calculation when predicting the height distribution of the substrate surface on the mounting stage. Below, we will explain the steps shown in the flowchart in FIG.

[0047] STEP 1 in FIG. 3 is a temporary stage surface height distribution measurement process for determining the surface height distribution of the temporary stage 5. In STEP 1, the surface height distribution of the temporary stage 5 on which the substrate S is not placed is determined, as shown in FIG. 4. When measuring the surface height, as shown in FIG. 5(a), a height distribution measurement means 60 measures the surface height of the temporary stage 5 at multiple points on the plane of the temporary stage surface 5F as shown in FIG. 5(b), and the height distribution data is stored in the control unit 10. In FIG. 5(b), (XM, YN) represent the XY coordinate positions on the temporary stage surface 5F. Here, M is a natural number, and XM is X1, X2, X3, etc., and N is also a natural number, and YN is Y1, Y2, Y3, etc.

[0048] STEP 2 in FIG. 3 is a mounting stage surface height distribution measurement process for determining the surface height distribution of the suction table 23 (of the mounting stage 2). In STEP 2, the surface height distribution of the suction table 23 without the substrate S placed thereon is determined, as shown in FIG. 4. To measure the surface height, the height distribution measurement means 61, as shown in FIG. 6(a), measures the surface height of the suction table 23 at multiple points on the suction table surface 23F as shown in FIG. 6(b), and the height distribution data is stored in the control unit 10. In FIG. 6(b), (XM', YN') represent the XY coordinate positions on the temporary stage surface 5F. Here, M' is a natural number, and XM' is X1, X2, X3, etc.; N' is also a natural number, and YN' is Y1, Y2, Y3, etc.

[0049] In FIG. 3, STEP 2 is performed after STEP 1, but the order of STEP 1 and STEP 2 is not limited to this; the contents of STEP 2 may be performed first, or STEP 1 and STEP 2 may be performed simultaneously.

[0050] After performing at least STEP 1, the mounting device 1 uses the substrate transport means 8 to place the substrate S on the temporary placement stage 5, and the temporary placement stage 5 adsorbs and holds the substrate S. This is shown in Figure 7, and STEP 3 in Figure 3 is performed in the state shown in Figure 7.

[0051] STEP 3 is a temporary substrate surface height distribution measurement process for determining the surface height distribution of the substrate S (partially on the temporary stage 5) while the temporary stage 5 holds the substrate S. To measure the surface height, as in STEP 1, the height distribution measurement means 60 measures the height of the substrate surface SF on the temporary stage 5 at multiple points on the plane of the temporary stage surface 5F as shown in FIG. 8(b), and the height distribution data is stored in the control unit 10. In FIG. 8(b), (XM, YN) represent the XY coordinate positions on the temporary stage surface 5F. Here, M is a natural number, and XM is X1, X2, X3, etc.; N is also a natural number, and YN is Y1, Y2, Y3, etc.

[0052] From the data obtained in STEP 1 and STEP 3, the thickness distribution of the substrate S can be obtained in STEP 4. That is, the distribution of the substrate thickness SF of the substrate S as shown in Fig. 9 can be obtained by subtracting the data obtained in STEP 1 from the data obtained in STEP 3, and this is stored as data on the substrate thickness distribution. That is, STEP 4 is a substrate thickness distribution calculation step in which the thickness distribution of the substrate is calculated from the results obtained in the temporary placement stage surface height distribution measurement step and the temporary placement substrate surface height distribution measurement step.

[0053] After performing STEP 3, the mounting device 1 has the control unit 10 control the substrate transport means 8 to retrieve the substrate S from the temporary placement stage 5 (FIG. 10), transport it to the mounting stage 2 side (FIG. 11), and after placing it on the mounting stage 2, control the mounting stage 2 to suck and hold the substrate S on the suction table 23 (FIG. 12). Data calculation in STEP 4 may be performed in parallel with the operations of the mounting device 1 shown in FIGS. 10 to 12.

[0054] In STEP 5, the surface height distribution of the substrate S when the suction table 23 (of the mounting stage 2) suction-holds the substrate S can be predicted by calculation from the mounting stage surface height distribution data obtained and stored in STEP 2 and the substrate thickness distribution data calculated and stored in STEP 4. In other words, STEP 5 can be said to be a substrate surface height distribution calculation process.

[0055] The above has been explained up to STEP 5 according to the flowchart in Figure 3, and thereafter, as indicated as the process, chip components C are mounted on the substrate S. During mounting, the amount of lowering of the mounting head 4 (before alignment) is adjusted based on the results obtained in STEP 5 so that the gap between the chip components C and the substrate S during alignment is constant every time (for each chip component C). At this time, if a head height measuring means is provided that measures the height of the holding surface (or the bottom surface of the held chip component C) of the mounting head 4 that holds the chip component C, it becomes possible to control the gap between the chip component C and the substrate S with high precision every time.

[0056] After chip components C have been mounted on all of the predetermined mounting locations on the substrate S, if there is no need to replace the stage 2 or the temporary placement stage 5, it is not necessary to perform STEP 1 and STEP 2 each time, and you can proceed to STEP 3. This is because the surface height distribution of the temporary placement stage 5 and the surface height distribution of the suction table 23 do not change easily.

[0057] Figure 13 explains STEP 13 using cross-sectional views of the suction table 23 and the substrate S. Here, Figure 13(a) shows the cross-section of the suction table 23 for which the surface height distribution was calculated in STEP 2, Figure 13(b) shows the state in which the substrate S, for which the thickness distribution was calculated in STEP 4, is not held by suction on the suction table 23, and Figure 13(c) shows the state in which the substrate S is held by suction on the suction table 23. In Figure 13(c), it can be seen that if the surface height distribution of the suction table 23 and the thickness distribution of the substrate S are known, it is possible to predict the thickness distribution of the substrate S held by suction on the suction table 23.

[0058] However, even if the surface height distribution of the suction table 23 and the thickness distribution of the substrate S are known, the surface height distribution of the substrate S will differ depending on the in-plane position of the suction table 23 that holds the substrate S. Furthermore, when obtaining thickness distribution data of the substrate S in STEP 3, an accurate thickness distribution cannot be obtained unless the in-plane position of the temporary stage 5 that holds the substrate S by suction is known.

[0059] Therefore, it is desirable to determine the arrangement of the substrate S adsorbed by the temporary placement stage 5 and the arrangement of the substrate S adsorbed by the suction table 23, and as a modified embodiment of the present invention, an external view of a mounting apparatus 1001 is shown in Fig. 14. The mounting apparatus 1001 in Fig. 14 is equipped with an imaging means 70 for acquiring arrangement information of the substrate S adsorbed and held by the temporary placement stage 5, and an imaging means 71 for acquiring arrangement information of the substrate S adsorbed and held by the suction table 23. 15 is a block diagram showing the control system of the mounting device 1001, in which the imaging means 70 and the imaging means 71 are connected to a control unit. Also, the surface height prediction device 111 has a configuration in which the imaging means 70 and the imaging means 71 are added to the surface height measurement device 11 in FIG.

[0060] In the mounting device 1001, the control unit 10 is connected to the imaging means 70 and has a function of acquiring and storing position information of the substrate S within the temporary placement stage 5 from image data acquired by the imaging means 70. The control unit 10 is also connected to the imaging means 71 and has a function of acquiring and storing position information of the substrate S within the suction table 23 from image data acquired by the imaging means 71.

[0061] Hereinafter, as a modified example of the embodiment of the present invention, an example of processing of position information performed by a mounting device 1001 having an imaging unit 70 and an imaging unit 71 will be described.

[0062] FIG. 16 is a diagram showing a temporary placement measurement process in which the placement of the substrate S held by suction on the temporary placement stage 5 of the mounting device 1001 is acquired by the imaging means 70.

[0063] 17(a), the temporary placement measurement process determines the placement of the substrate S in a coordinate system that defines the position (XM, YN) where the surface height measurement is performed. Specifically, the positions of the substrate recognition first mark SA1 and the substrate recognition second mark SA2 (when neither is specified, they are referred to as the substrate recognition mark SA) that are provided on a diagonal line near the edge of the substrate S are determined in the coordinate system of the temporary placement stage surface 5F.

[0064] Thereafter, the thickness distribution of the substrate S at a position (XM, YN) relative to the temporary stage surface 5F is calculated by subtracting the data on the height distribution of the temporary stage surface obtained in STEP 1 from the data on the height distribution of the temporary substrate surface obtained in STEP 3. However, it is desirable to associate the film thickness of the substrate S with a position on the substrate surface SF relative to the substrate recognition mark SA. In this case, as shown in FIG. 17(b), a coordinate position (xm, yn) on the substrate surface SF may be newly set, and the thickness of the substrate S at each coordinate position may be calculated by interpolation or the like. Here, m is a natural number, and xm is x1, x2, x3, etc., and n is also a natural number, and yn is y1, y2, y3, etc.

[0065] After this, the substrate S is removed from the temporary placement stage 5, and as described above, the film thickness distribution is calculated in relation to the position of the substrate surface SF, which is set using the substrate recognition mark SA as a reference. After being removed from the temporary placement stage 5, the substrate S is transported to the mounting stage 2 side and is held by suction on the suction table 23. In this state, the position of the substrate S relative to the suction table 23 is acquired by the imaging means 71 as part of the substrate position measurement process, as shown in FIG. In the substrate position measurement process, the position of the substrate S (FIG. 19(a)) relative to the coordinate system (XM', YN') of the suction table surface 23F is obtained (the state of FIG. 19(b)). Specifically, the positions of the substrate recognition first mark SA1 and the substrate recognition second mark SA2 in the coordinate system of the suction table surface stage 5 are obtained.

[0066] In this way, since the arrangement state of the substrate S on the suction table surface 23F can be known, the surface height distribution of the substrate S suction-held on the suction table 23F can be accurately known.

[0067] In order to obtain height information for each position where the chip component C is mounted, it is desirable to use a height distribution calculated in a coordinate system (xm, yn) on the substrate surface SF as shown in Figure 19(b), but it is also possible to use a height distribution calculated in a coordinate system (XM', YN') on the suction table surface 23F as shown in Figure 19(c).

[0068] Incidentally, if the arrangement of the substrate S on the temporary placement stage surface 5F and the arrangement of the substrate S on the suction table surface 23F are the same every time, there is no need to perform calculations associated with changes in the coordinate system, and therefore an apparatus configuration may be adopted in which the substrate S can be arranged on the temporary placement stage 5 and the suction table 23 with a predetermined accuracy. Specifically, recognition marks for alignment according to the shape of the substrate S may be provided on the temporary placement stage 5 and the suction table 23, and the substrate recognition marks SA may be observed by the imaging means 70 or the imaging means 71, respectively, and the arrangement position may be adjusted by the substrate transport means 8. The accuracy during arrangement is within 5 mm, preferably within 2 mm, since the in-plane tilt of each height and thickness is relatively small.

[0069] As explained in the above embodiments, the present invention makes it possible to predict the height distribution of the substrate surface on the mounting stage in advance, even if the substrate has thickness variations. This reduces the variation in the distance between the chip component and the substrate even when they are positioned within a distance of approximately 100 μm, and also reduces the slight measurement error caused by the variation in the distance during alignment. This improves the accuracy of mounting chip components on the substrate, making submicron-level mounting precision possible.

[0070] Furthermore, because data on the thickness distribution of the board can be obtained before it is attached to the mounting stage, and the surface height distribution of the mounting stage (suction table) can also be obtained in advance, data on the surface height distribution of the board can be obtained when the mounting stage holds the board by suction. Therefore, predicting the board surface height where chip components will be mounted does not extend the takt time. In other words, high-precision mounting is possible without reducing productivity. [Explanation of symbols]

[0071] 1 Mounting equipment 2. Implementation Stage 3 Lifting means 4 Mounting head 5 Temporary Stage 5F Temporary stage surface (top) 8. Substrate transport means 10 Control Unit 11, 111 Substrate surface height prediction device 21 X direction movement means 22 Y-direction movement means 23 Vacuum table 23F Mounting stage surface (suction table surface) 60 height distribution measuring means (second height distribution measuring means) 61 height distribution measuring means (first height distribution measuring means) 70 Imaging means 71 Imaging means 80 Transport rail 81 Board holding part 100 bases S board SA1, SA2 board recognition marks SF board surface TS board thickness

Claims

1. A substrate surface height prediction device that predicts the height distribution of a substrate held by suction on a mounting stage, a first height distribution measuring means for measuring a surface height distribution of the mounting stage; a temporary placement stage that is provided separately from the mounting stage and is capable of suction-holding a substrate; a second height distribution measuring means for measuring a surface height distribution of the temporary placement stage; a control unit connected to the first height distribution measuring means and the second height distribution measuring means, the control unit having a function of inputting each measurement data, a calculation function, and a storage function;

2. 2. The substrate surface height prediction device according to claim 1, the second height distribution measuring means also measures the surface height distribution of the substrate held by suction on the temporary placement stage; The control unit calculates the thickness distribution of the substrate from the surface height distribution of the substrate and the surface height distribution of the mounting stage.

3. 3. The substrate surface height prediction device according to claim 2, The control unit stores the surface height distribution of the mounting stage and the thickness distribution of the substrate, and calculates and predicts the height distribution of the substrate held by suction on the stage from the surface height distribution of the mounting stage and the thickness distribution of the substrate.

4. a mounting head disposed above the mounting stage and connected to the control unit, the mounting apparatus mounting chip components held by the mounting head onto the substrate on the mounting stage, When mounting the chip component on the substrate, 4. A mounting apparatus that adjusts the amount of lowering of the mounting head in accordance with the substrate surface height directly below the mounting head, the substrate surface height being determined from the substrate surface height distribution predicted by the substrate surface height prediction apparatus according to claim 1.

5. The mounting device according to claim 4, The mounting head has a head height measuring means for measuring the height of the surface that holds the chip component.

6. A substrate surface height prediction method for predicting a surface height distribution of a substrate held by suction on a mounting stage, comprising: a temporary placement stage surface height distribution measurement process for measuring the surface height distribution of a temporary placement stage that is provided separately from the mounting stage and is capable of suction-holding a substrate; a temporary placement substrate surface height distribution measurement process for measuring the surface height distribution of the substrate suction-held by the temporary placement stage; a substrate thickness distribution calculation process for calculating the thickness distribution of the substrate from results obtained by the temporary placement stage surface height distribution measurement process and the temporary placement substrate surface height distribution measurement process; and a substrate surface height distribution calculation process for calculating and predicting the surface height distribution of the substrate suction-held by the stage using the surface height distribution of the mounting stage obtained in the mounting stage surface height distribution measurement process and the thickness distribution of the substrate calculated in the substrate thickness prediction process.

7. 7. A method for predicting a substrate surface height according to claim 6, comprising: Between the temporary-placement substrate surface height distribution measuring step and the substrate surface height distribution calculating step, A substrate surface height prediction method comprising a substrate placement measurement step for determining the placement of the substrate within the mounting stage surface.

8. A mounting method for mounting chip components on the substrate held by the mounting stage by suction, comprising: In the process of bringing the chip component close to the surface of the substrate, 8. A mounting method for predicting a distance between the chip component and the substrate surface using the surface height distribution of the substrate obtained by the substrate surface height prediction method according to claim 6.

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