JP5167072B2 - Flip chip bonder - Google Patents

Description

The present invention relates to a flip chip bonder device that adsorbs, picks up, inverts and connects an electronic component that is attached to an adhesive sheet and cut out from a wafer to a substrate.

A wafer is a disk-shaped plate made by thinly slicing an ingot, which is a material for manufacturing a semiconductor element, and in which a crystal of a semiconductor material such as silicon is grown in a cylindrical shape. The thickness of the plate is about 0.03 mm to 1 mm.

  This plate is provided as an electronic component (hereinafter referred to as a chip) in which an integrated circuit is formed in a state where the surface is developed / etched, adhered to an adhesive sheet with the resist removed, and finely diced.

The chip is a square having a side of about 1 mm to 30 mm square, and is sucked and transported by a nozzle or the like of the work head, and mounted on the circuit board or the like by heat and pressure bonding.
The present application relates to an apparatus used when a chip is connected to a circuit board (hereinafter referred to as a substrate) using a bump attached to the chip, which is also called a flip chip bonder apparatus.

The flip chip bonder is configured to invert a chip provided by a wafer with a reversing head, suck and hold it with a working head, and heat and press bond it to a substrate.
At this time, the bonding stage on which the substrate is placed must always move within the working range in parallel with the working head. If the bonding stage is inclined, the working head cannot maintain a certain distance from the substrate, and the heat-pressure bonding is not performed well, which may cause defective products.

  Therefore, conventionally, as disclosed in Japanese Patent Application Laid-Open No. 2005-28202 shown in FIG. 8, a dial gauge is attached to the nozzle base (not shown), moved on the table 90, and the handle 91 at the four corners is rotated by a human hand to rotate the table 90. These four corners were adjusted to be parallel to the nozzle base by being moved up and down, and held and fixed by a push screw 92.

Further, as a conventional example, a head measuring device 96 is attached to the stage 95 as in JP-A-2002-110743 shown in FIG. 7, a stage measuring device 97 is attached to the head 99, and three points on a non-collinear line are attached. There is provided a bonding apparatus configured to measure and calculate the position and adjust the inclination of the surface of the head or the stage by the inclination adjustment mechanism 98.

JP2005-28202 JP2002-110743

  In the method as shown in Patent Document 1, the heights of four locations must be manually adjusted. This is a very difficult task. In particular, in a precision machine such as a flip chip bonder device used in the present application, only an error of about several μm is allowed, and much time must be spent for manual adjustment.

In addition, since the flip chip bonder is a device that joins the chip and the substrate by heat and pressure bonding, a temperature raising mechanism is built in the bonding stage 19 on the work table plate 20 to warm the substrate by raising the temperature to a certain temperature. There is. The heat is transmitted to the pedestal portion over time, which may cause an error in the parallelism of the work table plate due to thermal expansion.
Therefore, the parallelism must be inspected and adjusted in a short time many times within a certain time during the heat and pressure bonding operation.

In addition, the working head may press the chip against the substrate with a force of several tens of kilograms, and if the work table plate that receives the pressing force is supported by three or more fulcrums, a floating fulcrum will occur, and the pressing position Depending on the case, the work table may be slightly moved.
As shown in Patent Document 1, if it is held by the push screw 92, the fulcrum that floats can be prevented, but it is necessary to loosen the push screw every time the parallelism is adjusted. Further, it is conceivable that the adjusted parallelism is shifted when the push screw 92 is pushed.

Patent Document 2 touches on the measurement method and the tilt adjustment mechanism between the work table plate and the head, but does not clearly show how to adjust by moving up and down.
Further, although it is described that laser light is used as a measuring method, it cannot be corrected when the positional relationship between the measuring device that generates the laser light, the head, and the measuring device and the work table plate changes due to thermal effects.

It should be noted that the work base plate and the work head must be moved as fast as possible in order to increase the work speed and be compatible with heat-pressure bonding. For this purpose, the work table firmly follows the movement of the XY table and is restrained by the XY table while avoiding distortion and the like so as not to generate distortion and residual stress due to vertical movement and heat effects to maintain parallelism. It must be placed so that
In Patent Document 1, it is difficult to release the distortion generated by the thermal effect, and in Patent Document 2, it is not clear how to solve the above problem and adjust the parallelism by moving up and down.

  Therefore, a work board on which the circuit board is placed, an XY table on which the work board is movably mounted within a work range, and a work that moves up and down to heat and pressurize the chip to the circuit board. The work surface of the work base plate is supported by the head, the jack means that is fixed to the XY table and moves up and down the support shaft by driving the motor, and the work base plate is supported by the three jack means. A control unit that regulates so as to intersect at right angles to the central axis of the working head, and the height of the work base plate by bringing the working head into contact with the work plate or the circuit board at a plurality of predetermined positions. And the control unit controls the support shaft to move up and down by the three jack means so that the heights at the plurality of predetermined positions are constant. And there is provided a flip-chip bonder.

The upper portion of the support shaft is formed with a V-shaped recess, and the V-shaped recess is arranged at an angle of 120 degrees with respect to the center of the work table plate. Flip chip bonder device, wherein a base plate shaft is attached to three positions on the back surface of the work base plate, the lower portion of the base plate shaft is formed in a spherical shape, the V-shaped of the support shaft It is a flip chip bonder characterized by being formed so as to be in point contact with a recess.
The jack means includes a worm that rotates by driving the motor, a worm wheel that meshes with the worm, and the support shaft that is screwed with the worm wheel, and the worm and the worm wheel; The flip-chip bonder device is configured to prevent the support shaft from being lowered by a holding torque of the motor by a self-locking action generated by a speed reduction mechanism by engagement of the motor, wherein the working head is connected to the work table. Data measured by contacting a plate at a certain elapsed interval during work, work height change information, average data that stores the work height change information and correlates with elapsed time, and the work height change information Is measured several times, and the average value of the work progress height created in the data correlated with the elapsed time in the calculation unit The flip chip bonder apparatus is characterized in that the motor is controlled to be driven so that the height of the work base plate becomes constant according to the average value of the work progress height.

In the invention according to the present application, the measuring jig 39 and the substrate 18 are moved by the head motor 45 that moves the working head 40 up and down by bringing the measuring jig 39 attracted by the working head 40 into contact with the substrate 18 or the bonding stage 19. Since the distance or the distance between the measuring jig 39 and the bonding stage 19 is measured, the measuring operation can be performed in a short time.
The motors used in this device are all pulse motors or servo motors. In the case of a servo motor, a rotary encoder is built in the motor, and the rotary encoder rotates the motor many times in either direction at what speed. It is configured to transmit to the control unit 2 by pulses to control whether or not. Therefore, in the case of a servo motor, it is always managed by the control unit 2, and the position where the motor stops is also confirmed by the control unit 2.
In the case of a pulse motor, since a rotary encoder is not built in, it is provided at low cost. The motor rotates the number of pulses transmitted from the control unit, but since there is no rotary encoder built-in, it is not possible to determine at which position it is stopped, so the control unit cannot determine the motor capacity. If appropriate, accurate positioning is possible. Usually, it is often used when the moving part can be measured and positioned by another sensor or the like.

In addition, a force sensor 42 is disposed on the upper portion of the working head 40 so that it can be determined that the measuring jig 39 has come into contact with something when it comes into contact. This force sensor 42 is used to control and measure the applied pressure during the heat and pressure bonding operation.
The force sensor 42 is used to measure the distance between the working head 40 and the work base plate 20, and since the measurement is performed in a state close to actual work, errors can be reduced. That is, the measurement method of the present invention is a method in which the work table plate 20 and the work head 40 are brought into contact with each other for direct measurement, so that the measurement unit and the work unit are the same, and there is little error.

The work height change information measured several times is stored and calculated in the calculation unit 3, and an average value is created by the calculation unit 3 as work progress height average data R. If the work height average data R starts work and the time passes and the measured value that changes the parallelism of the work base plate 20 with the thermal effect and the error disappears, the number of measurements is reduced and the work efficiency is increased. Will be able to.
In other words, if the control unit is controlled so that the height of the work base plate 20 is constant according to the work progress height average data R, the measurement work can be made intermittent and the work speed can be increased accordingly. it can.

Measurement is possible without an error of several μm, and even if the length of the working head 40 and the height of the work base plate 20 are deformed due to thermal expansion, the parallelism is adjusted and held in the deformed state. be able to. Therefore, there are few errors in actual heat-pressure bonding.

Since the work base plate 20 is supported by three base plate shafts 30 and the base plate shaft 30 is disposed so as to engage with the grooves of the three support shafts 31 disposed at an angle of 120 degrees, the work base plate 20 Even if it is deformed by thermal expansion, the stress can be released.

Further, the work base plate 20 is manufactured to be sufficiently thick so as not to bend. However, even if bending stress is generated due to thermal expansion or heat-pressure bonding, the spherical surface portion of the base plate shaft 30 and the support shaft 31 Stress is not generated by the point contact action by the V-shaped groove.

Since the work base plate 20 is configured to be supported at three points, a floating fulcrum does not occur. Accordingly, since the work table 20 does not slightly move when pressurized, accurate joining is possible.
Even if there are no holding bolts or the like, if the work base 20 is of sufficient weight, the parallelism can be automatically maintained by raising and lowering the support shaft 31. Even if the weight of the work table 20 is insufficient, it is configured so that several points can be fastened to the holding table 21 with springs or the like so that the work table 20 is not lifted by pressurization. May be.
Further, since the support shaft 31 and the worm wheel 32 are screwed together and the worm 33 is rotated by driving the worm motor 34, the support shaft 31 is kept at a certain height even if the holding torque of the worm motor 34 is small. Can be held in.

The V-groove of the support shaft 31 is evenly arranged at an angle of 120 degrees, and the work table plate 20 supported by the base plate shaft 30 engaged with the V-groove has a high horizontal work speed by the XY table 21. Even if it becomes, it is point contact and does not move finely.

The present invention is a method of measuring the height of three positions of the work base plate 20 based on the principle of triangulation, detecting a difference in height from the same reference height of the three positions, and adjusting the position by vertically moving the three support shafts. There is a reasonable adjustment method with minimal measurement and drive.

The present invention relates to a flip chip bonder device that only allows an error of about several μm, and the work head 40 and work table plate 20 are gradually deformed due to the heat effect during heat-pressure bonding over a long period of time. It is intended to prevent the occurrence of defective products in the manufactured parts.

Therefore, periodically (every time the work process is completed in several cools), the work head 40 holding the measurement jig 39 is lowered and brought into contact with the work board 20 to match the position of the work head 40. The plate 20 is configured to be automatically parallel. Details will be described below.

As shown in FIG. 1, the semiconductor chip is installed on the wafer table 16 in the state of the wafer 19 adhered to the adhesive sheet and is moved in the X direction by the motor 161.
The semiconductor chip on the wafer 19 is peeled off from the wafer 19 by being sucked and held by the reversing head 17 and moved in the Y direction by driving the motor 171 and the reversing head 17 is turned upward by driving the motor 172. Thus, the semiconductor chip is delivered to the working head 40 at a predetermined position.

  The working head 40 is sucked and held at the lower part of the heater 41 by being sucked by the head suction passage 401 and heated by the heater 41. Further, the semiconductor chip is sucked and held at the lower portion of the working head 40 by sucking from the chip suction passage 402.

With the above configuration, during normal operation, the semiconductor chip sucked and held by the work head 40 is heated by the heater 41 and is heated and pressed to a predetermined position on the substrate 18.
The pressure of the semiconductor chip is such that the head ball screw shaft 46 is rotated and screwed by the head motor 45 (servo motor), so that the head ball screw nut 47 is raised and lowered, and the shaft 44 can be moved in the Z direction. With these configurations, the semiconductor chip adsorbed by the working head 40 can be pressed against the substrate 18.

Further, as shown in FIG. 2, a force sensor 42 is attached to the lower portion of the shaft 44 so that it can be measured how much the pressing force is applied to the semiconductor chip 18 against the substrate 18.
A cooling unit 43 is attached to the lower part of the force sensor 42, and is cooled by the cooling air blown from the cooling blowing port 431. The heat generated by the heater 41 is transmitted to the upper part, and the shaft 44 and the vicinity thereof are not deformed by the heat effect. Is taken into account.

However, if the work is continued for a long time, the ambient temperature also rises, and the possibility that heat is transferred to the shaft 44 to cause an error due to thermal expansion is also considered.
When measuring the distance between the working head 40 and the substrate 18 or the bonding stage 19, the measurement jig 39 is attracted and held under the working head 40 so as to make point contact with the substrate 18 or the bonding stage 19. Is considered.

The motors used in various parts of the apparatus of the present invention are all pulse motors or servo motors. In the case of servo motors, a rotary encoder is built in. The motor is configured to be able to determine how much the motor has rotated in which direction by generating a rotation pulse in accordance with the rotation speed and rotation angle, and measuring and calculating the rotation pulse by the control unit. Therefore, the head ball screw shaft 46 and the head ball screw nut are arranged so that the head ball screw nut 47 which is screwed by rotating the head ball screw shaft 46 by the head motor 45 (servo motor) is moved up and down. If the screw pitch of 47 is known, the position of the head ball screw nut 47 can be determined by calculating the rotation of the head motor 45, whereby the position of the working head 40 can also be determined.

  Further, even if the shaft 44 is thermally expanded due to the thermal influence as described above, if the height of the work base plate 20 is adjusted according to the thermally expanded position, the distance by which the work head 40 descends is always constant. Can be.

  When measuring to make the height of the work table plate 20 constant and parallel to the work head 40 by bringing the work head 40 into contact with the substrate 18 or the bonding stage 19 or the work table plate 20 Then, the measuring jig 39 with a sharp tip is sucked and held on the work head 40 and brought into contact with the substrate 18, the bonding stage 19, and the work base plate 20 so that all the contacts are fixed distance from the work head 40. It is adjusted to become.

  Further, as described above, the force sensor 42 is installed on the upper part of the working head 40, and a pressing force is generated when the measuring jig 39 comes into contact with the substrate 18, the bonding stage 19, and the work table plate 20. The distance to the working head 40 is determined from the rotation pulse of the head motor 45 at that time.

Next, the work table 20 will be described with reference to FIG. 3, FIG. 4, and FIG. The work table 20 is placed on the holding table 21 fixed to the XY table 22 so that three points are supported.
As shown in FIG. 2, the XY table 22 moves in the X direction by driving a motor 221, and moves in the Y direction by driving a motor 222. The XY table 23 is fixed to the main body 1.

As shown in FIG. 2, the holding table 21 is fixed to the XY table 22. As shown in FIG. 4, the jack means 35 is fixed at three places on the holding table 21, and the three support shafts 31 (first support shaft 311, second support shaft 312; A third support shaft 313) is attached.

The upper portion of the support shaft 31 is formed with a V-shaped concave portion, and the concave portions of the three support shafts 31 have different directions by 120 degrees.
The V-shaped concave portions of the support shaft 31 have different directions, and the direction of the grooves of the concave portions is equal to the central portion or the center of gravity of the work table plate 30 mounted on the central portion or the upper portion of the holding table 21. It is arranged to be at an angle of 120 degrees. That is, they are arranged in a Y shape.

  As shown in FIG. 3, the work table 20 is placed on the holding table 21. A base plate shaft 30 is attached to three positions on the back surface of the work base plate 20, and a lower end portion of the base plate shaft 30 is formed in a spherical shape, and is engaged with a V-shaped concave portion of each base plate shaft 31. It is formed so as to be in point contact.

Even if the XY table 22 is moved by such an attachment method, the base plate shaft 30 engaged by the V-shaped concave portion of the support shaft 31 arranged every 120 degrees is not moved.
Further, even if the work table plate 20 expands and contracts due to the heat effect, the internal stress is released and no distortion is generated.

  Further, it is considered that the work table plate 20 is supported as described above at three points so that it does not move finely even when the work table 20 is pressed by the work head 40. However, even if the weight of the work base plate 20 is insufficient, the work base plate 20 is not lifted up by partial pressurization of the work base plate 20 by fastening several points to the holding table 21 with springs or the like. You may comprise so that it can supplement.

  Next, the jack means 35 will be described. As shown in FIG. 5, the jack means 35 is fixed to the holding table 21. The jacking means 35 includes a worm motor 34, a worm 33, a worm wheel 32, a support shaft 31, and the like.

  When the worm 33 is rotated by driving the worm motor 34, the worm wheel 32 engaged with the worm 33 is rotated. Since the reduction ratio between the worm 33 and the worm wheel 32 is large, a self-lock mechanism is generated so that the worm 33 cannot be rotated from the worm wheel 32 due to the gear ratio, and the support shaft 31 can be prevented from descending. .

  As the worm wheel 32 rotates, the support shaft 31 screwed with the worm wheel 32 can be moved up and down.

  Further, since the reduction ratio of the worm 33 and the worm wheel 32 is large, the holding torque of the small worm motor 34 sufficiently supports the dead weight of the work base plate 20 even if the above self-locking mechanism does not work, and the support shaft 31 The descent can be prevented.

The operation of the flip chip bonder configured as described above will be described. As described above, the apparatus according to the present invention is an apparatus for adhering and holding the chips of the wafer 162 to the working head 40 and bonding them to the substrate 18 by heat and pressure.
An apparatus for automatically measuring and adjusting whether or not the work base plate 20 on which the substrate 18 is installed is parallel to the work head 40 is provided.

The measurement method using the working head 40 will be described. The normal working head 40 sucks and holds the chip delivered from the reversing head 17 and bonds it to the substrate 18 by heating and pressing. However, when measuring the parallelism of the work table plate 20, the measurement jig 39 is held by suction. The measuring jig 39 has a pointed tip and is made so that the contact portion is a point contact.
When the step of measuring the parallelism of the work table 20 is started, the working head 40 sucks and holds the measuring jig 39 installed and stored at a predetermined position (not shown). The above is the start step f1.

  Next, the working head 40 moves to a position (working position) where the chip is heated and pressed. The position at which the working head 40 descends is set in advance in the control unit 2 so that the position of the work table plate 20 in FIG. 3 is the point P1, and the XY table unit 23 is moved. The above is the XY table first point movement step f2.

  Next, the working head 40 that has reached just above the point P 1 of the work table plate 20 is moved up and down by the drive of the head motor 45. When the measurement jig 39 comes into contact with the work table plate 20, the force sensor 42 detects the load change, and the control unit 2 senses that the measurement jig 39 has come into contact with the work table plate 20. Then, the height of the tip of the measuring jig 39 at that time, that is, the height of the point P1 is measured by the rotary encoder of the head motor 45. The above is the first point measurement step f3.

  Next, the working head 40 once rises to a predetermined height and stops at the working position. Then, the XY table unit 23 is moved so that the position immediately below the work position of the work head 40 is the position of the point P2 of the work table plate 20. The above is the XY table second point moving step f4.

The working head 40 descends to the point P2 on the work table plate 20, and the tip of the measuring jig 39 comes into contact with the point P2 to measure the height of the point P2. The above is the second point measurement step f5.
Next, the working head 40 once rises to a predetermined height and stops at the working position. Then, the XY table unit 23 is moved so that the position immediately below the work position of the work head 40 is the position of the point P3 of the work table plate 20. The above is the XY table third point moving step f6.

  The working head 40 descends to the point P3 on the work table plate 20, and the tip of the measuring jig 39 comes into contact with the point P3 to measure the height of the point P3. The above is the third point measurement step f7.

  If the triangle drawn by the three points P1, P2, and P3 measured so far matches the triangle drawn by the three points Q1, Q2, and Q3 assumed in advance by the calculation unit 3, the work table 20 will work. It is parallel to the head 40 for use. Such a calculation is performed in calculation step f8.

  If the triangle drawn by the three points P1, P2, and P3 as shown in FIG. 3 is calculated and the work table 20 is parallel to the work head 40, the assumed Q1, Q2, and Q3 3 It is determined whether or not the triangle drawn by the point coincides with the height adjustment allowable range. The above is the height adjustment allowable range step f9.

If the triangles drawn by P1, P2, and P3 coincide with the triangles drawn by Q1, Q2, and Q3 within the height adjustment allowable range, the height adjustment work of worktable plate 20 is finished. The above is the end step f13. The working head 40 continues the normal operation of returning the measuring jig 39 to a predetermined position and bonding the chip to the substrate 18 by heating and pressing.
If the triangle drawn by the points P1, P2, and P3 does not match the triangle drawn by the points Q1, Q2, and Q3 within the allowable range in the height adjustment allowable range judgment step f9, operate the three jack means 35. The support shaft 31 that supports the work table 20 is controlled by the control unit 2 based on the calculation result of the calculation unit 3 and moved up and down respectively, and the triangles drawn by the points P1, P2, and P3 are the triangles drawn by the points Q1, Q2, and Q3. The work table 20 is adjusted so as to match. This is the height adjustment execution step f10.

  In the next process, the designated number of completion steps f11 is set. The specified number of times is usually entered here. According to the procedure of height adjustment execution step f10, the work base plate 20 is adjusted according to the calculation of the calculation unit 3, but it is actually measured whether the work base plate 20 is adjusted according to the calculation or if there is no mistake in the calculation. I can't judge it. Therefore, the procedure is set so that the procedure of f2 to f10 is repeated the number of times specified in the specified number of times completion step f11.

Within the allowable range of height adjustment within the number of times specified in step f11 If the adjustment can be made within the allowable range at step f9, the height adjustment work of worktable plate 20 is completed, and the chip is heated and pressure bonded to substrate 18. Return to normal work.
If the number of times f2 to f10 designated in the designated number of times completion step f11 is repeated, there is a possibility that something is wrong (parts are broken or dust is caught). Therefore, an error notification (for example, buzzer sound, lamp lighting, work stoppage, etc.) is performed. The above is the error notification step f12.

In the procedure of the error notification step f12, a means such as calling an operator (operator call) is performed, the work is interrupted, and the height adjustment work of the work base plate 20 is finished.
As described above, the height adjustment work of the work table 20 is performed. Note that the measurement of the points P1, P2, and P3 and the setting of the points Q1, Q2, and Q3 are performed on the workbench plate 20, but may be performed on the substrate 18 and the bonding stage 19 during the work.

  As described above, the work base plate 20 or the bonding stage 19 or the substrate 18 placed on the work base plate 20 is moved by the XY table unit 23, and the work head 40 that moves up and down is brought into contact with three predetermined positions. The height is measured, and triangulation is performed using points P1, P2, and P3, and if work table 20, bonding stage 19, or substrate 18 is parallel to work head 40, the virtual is drawn using points Q1, Q2, and Q3. The calculation unit 3 performs calculation so as to be the same height as the triangle.

The calculation unit 3 obtains the height differences h1, h2, h3 between the points P1, P2, P3 and the points Q1, Q2, Q3, and then selects the first support shaft 311, the second support shaft 312, and the third support shaft 313. It is calculated whether the height differences h1, h2, and h3 are within the allowable height range by moving up and down.
Then, the control means 2 controls the jack means 35 provided at three places to move the support shaft 31 up and down. As a result, the restricting means uses the functions of the calculation unit 3 and the control unit 2 for restricting the work surface of the work base plate 20 to intersect at right angles to the central axis of the work head 40.

  Further, there may be three or more points to be measured and three or more virtual points to be calculated. However, it is reasonable to define three points to define a plane. To the last, the XY table unit 23 is moved on the preset virtual point to lower the work head 40 and come into contact with the work base plate 20, and the difference between the actual contact position and the height of the virtual point is regulated (calculation unit). 3 and the function of the control unit 2).

V-shaped recesses are formed at the upper ends of the three support shafts 31 that move up and down in the jack means 35. Furthermore, the direction of the V-shaped concave portion is arranged in a state of, for example, the Y-shape so as to be an angle of 120 degrees toward the center portion of the work table plate 20.
Therefore, the base plate shaft 30 fitted in the V-shaped concave portions of the three support shafts 31 can follow and finely move even if the holding table fixed to the XY table 22 moves in the X direction and the Y direction. There is no.
Further, the lower end of the base plate shaft 30 is formed in a spherical shape, and is formed so as to make point contact with the V-shaped concave portion of the support shaft 31. Therefore, even if the work base plate 20 expands due to the heat effect and the positions of the three base plate shafts are slightly displaced, the work surface is flattened without causing internal work to be distorted. It becomes easy to be maintained.

  The jack means 35 is connected to a worm wheel 32 that rotates horizontally by a worm 33 that rotates by driving a worm motor 34. The gear ratio of the worm wheel 32 meshes with the rotation of the thread portion of the worm 33, so that the reduction ratio can be greatly changed. As a result, the self-locking action works and the worm 33 cannot be turned from the worm wheel 32. Therefore, the support shaft 31 screwed with the worm wheel 32 is not lowered by the weight of the work table plate 20.

Further, because of the combination of the worm 33 and the worm wheel 32 having a large reduction ratio, even the worm motor 34 having a small holding torque can be held so as not to drop due to the weight of the work base plate 20.
The procedure for lowering the work head 40 and measuring the heights of several points on the work base plate 20 and adjusting the height of the work base plate 20 each time is usually performed by heat-pressure bonding the chip to the substrate 18 It is done regularly in the meantime.
If the same kind of work is repeated, it is assumed that, as the work time starts, the result of the point height measurement as described above is almost the same result, and the adjustment of the control unit is repeated almost similarly.

  Therefore, all the data measured by bringing the work head 40 into contact with the work table 20 is accumulated in the calculation unit 3, and the work height change information measured at regular intervals during work and the work height change information are started. The average data correlated with the time is obtained, and when the work time is fixed and the fixed work time is reached without lowering the work head 40, the jack means 35 is automatically operated by the control unit 2, and the past experience The value is intended to cope with the work base plate 20 so as to be orthogonal to the central axis of the work head 40.

Thus, the measurement work of f1 to f8 in the operation flow depicted in FIG. 6 can be omitted, and the sentence work time can be made efficient.
With the above method, even if the shaft 44 and the gantry 4 are slightly deformed due to thermal influence, the work intersects at a constant distance from the work head 40 and at right angles to the central axis of the work head 40. The base plate 20 can be adjusted.

With the configuration as described above, the work head 40 directly contacts the work surface of the work base plate 20 for measurement, so that it is close to actual work and has few errors. Further, it is economical because it does not require a separate measuring device such as a laser beam.
In addition, since the measurement is performed directly using the working unit, the deformation due to the thermal effect can be reset and the measurement can be performed without being influenced by the deformed unit.
Since the angle P is measured by measuring the measured values P of the first to third points of the work table 20, it can be executed in a short time and is the same procedure as triangulation and is efficient.
Since the angle of the work base plate 20 is changed by the vertical movement of the first to third support shafts, it is efficient to produce parallelism without a fulcrum that rises.

Furthermore, as shown in FIG. 2, the present invention measures the height of the point P1 by steps f2 to f3 where the working head 40 is brought into contact with the work table plate 20, and similarly the height of the point P2 by steps f4 to f5. Measure the height of each of the points P3 by steps f6 to f7, and detect the height difference h1 to h3 from the points Q1 to Q3 which are the reference heights of the respective points. The height difference of the work base plate 20 can be detected by the most rational procedure.
Further, in the present invention, the arithmetic unit 3 moves the first to third support shafts up and down so that the height differences h1 to h3 between the measurement points P1 to P3 and the reference heights Q1 to Q3 are within an allowable range. The adjustment amount can be calculated easily and accurately by the adjustment amount calculation procedure.

Then, by vertically moving the first support shaft to the third support shaft based on the calculated adjustment amount, the work surface of the work base plate 20 accurately intersects the central axis of the work head 40 at a right angle. Can be set as follows.
In addition, it is possible to check the exact work surface by performing the above steps f2 to f10 for the specified number of times until the height difference h1 to h3 is within the allowable range, and there is some problem if adjustment is not possible with the specified number of times. An error notification is sent to prevent unnecessary operations from being repeated.

The present invention can be applied not only to the flip chip bonder device but also to a precision component assembly device composed of various heating parts.

FIG. 2 is a view showing the flip chip bonder device 1 in a state where the reversing head 17 has taken a semiconductor chip on a wafer 19; FIG. 2 is an enlarged view of a portion of the working head 40 in FIG. 1. The holding table 21 and the work table plate 20 are enlarged and the work table plate 20 is shown transparently. The configuration of the holding table 21 is shown with the work table 20 deleted. 4 is an enlarged view of the worm 33, the support shaft 31, and the base plate shaft 30 in FIG. The procedure for restricting the work table 20 to intersect at right angles to the central axis of the work head 40 is shown in the flowchart. This is a conventional example in which separate measuring instruments 96 and 97 are attached to keep the stage 95 horizontal with respect to the head 99. This is a conventional example in which four handles 91 are kept horizontal and are held by push screws 92.

Explanation of symbols

1
Flip chip bonder body
2
Control unit
Three
Calculation unit
Four
Stand
16 Wafer stand
161 motor
162 wafers
17 Reversing head
171 motor
172 motor
18 Board
19
Bonding stage
20 Worktable
21 Holding table
22 XY table
221 motor
222 motor
twenty three
XY table section
30 Base plate shaft
31
Support shaft
311
1st support shaft
312
Second support shaft
313
3rd support shaft
32
Worm wheel
33
Warm
34
Worm motor
35
Jacking means
39
Measuring jig
40
Working head
401
Head suction passage
402
Chip suction passage
41
heater
42
Force sensor
43
Cooling unit
431 Cooling inlet
44
shaft
45
Head motor
46
Headball screw shaft
47
Headball screw nut
90
table
91
handle
92
Push screw
95
stage
96
Head measuring instrument
97
Stage measuring instrument
98
Tilt adjustment mechanism
99
head

Claims (4)

A work table plate on which a circuit board is placed;
An XY table on which the work base plate is movably mounted within a work range;
A working head that moves up and down to heat and pressure bond the chip to the circuit board;
Jack means that is fixed to the XY table and moves up and down the support shaft by driving a motor;
By supporting the work table plate with the jack means in three places, a control unit that regulates the work surface of the work table plate so as to intersect at right angles to the central axis of the work head,
The control unit measures the height of the work base plate by bringing the working head into contact with the work plate or the circuit board at a plurality of predetermined positions, and the height at the plurality of predetermined positions becomes constant. And controlling the support shaft to move up and down by the three jack means as described above ,
Work height change information obtained by measuring data measured by bringing the working head into contact with the work base plate at regular intervals during work;
Average data correlated with elapsed time by storing the work height change information,
By measuring the work height change information multiple times and creating an average value of the work progress height created in the data correlated with the elapsed time in the calculation unit,
A flip-chip bonder characterized in that the motor is driven so that the height of the work base plate becomes constant according to the average value of the work progress height .
An upper portion of the support shaft is formed with a V-shaped concave portion, and the V-shaped concave portion is disposed at an angle of 120 degrees with respect to the center of the work table plate. 2. The flip chip bonder device according to claim 1.
A base plate shaft is attached to three positions on the back surface of the work base plate, and a lower portion of the base plate shaft is formed in a spherical shape, and is formed so as to be in point contact with a V-shaped concave portion of the support shaft. 3. The flip chip bonder device according to claim 1, wherein the flip chip bonder device is provided.
The jack means is a worm that rotates by driving the motor;
A worm wheel meshing with the worm;
The support shaft threadably engaged with the worm wheel,
2. The flip chip bonder according to claim 1, wherein the support shaft is prevented from lowering by a holding torque of the motor by a self-locking action generated by a speed reduction mechanism by meshing the worm and the worm wheel. .