JPH03211849A - Device for mounting flip chip - Google Patents

Abstract

PURPOSE:To accurately position a flip chip to a wiring board so as to bring them into uniform contact with each other by positioning the flip chip by means of a position adjusting means and fixedly connecting a bump electrode with a wiring conductor in a state where a pressing means is made to make second-stage operations. CONSTITUTION:A means which makes first-stage operations and second-stage operations which are smaller in moving quantity than the first-stage operations is used as the pressing means 10 of this device. The means 10 is made to make the first stage operations and positional deviation of a flip chip 1 to a wiring board 3 or the relative positional deviation between the chip 1 and board 3 are detected by means of an optical means 40 through the transparent board receiving base 31 of a board holding mechanism 30 in a state immediately before mounting the chip 1 on the board 3 where the chip 1 held by the front end face of the pressing rod 21 of a chip pressing mechanism 20 is brought nearer to the board 3 held on the transparent base 31. A position adjusting means 50 adjusts the relative position between the mechanisms 20 and 30 on the basis of the accurate detected results and makes the pressing means 10 to make the second-stage operations in such state so as to bring the bump electrode of the chip 1 into contact with the wiring conductor 5 of the board 3. Therefore, uniformity of the contact and positioning accuracy between the flip chip 1 and wiring board 3 can be improved even when many connecting points exist.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an apparatus for mounting a flip chip equipped with bump electrodes for an integrated circuit device on a wiring board, and in particular a device for mounting a flip chip equipped with bump electrodes for an integrated circuit device. The present invention relates to a device suitable for mounting flip chips provided at a very narrow arrangement pitch.

[Conventional technology]

Integrated circuit devices that drive display panels and printers are required to be able to drive as many loads, such as pixels and printing elements, with as small a chip size as possible, and since a connection is required for each load, it is necessary to use a small chip size of several squares. In such multi-terminal integrated circuit devices, in which hundreds of connection points must be arranged on a chip, conventional connection pads for wire bonding are difficult to arrange at a narrow pitch and the connection work is extremely troublesome. Therefore, it is very advantageous to use a flip chip that uses gold or solder bump electrodes as external connection points from the viewpoint of chip production and mounting.

The procedure for mounting such a multi-terminal flip chip will be briefly explained with reference to FIG.

FIG. 3 (Al shows the case where the bump electrodes are solder, and the flip chip 1 having a large number of bumps 1ii12a is mounted on an insulating base Fi11 with wiring conductors 5 arranged on it!Ill board 3
To mount the solder bumps on the wiring board Fi, 3 heated to the melting temperature of the solder, lightly press the flip chip 1 to bring the solder bumps I2a into contact with the corresponding wiring conductors 5 and melt them. By removing the force, the chip l is cooled in a self-aligned state with the wiring board 3 using the surface tension of the molten solder, and the solder is solidified.

Figures 3 to 3 show the case where the bump electrodes are made of gold or copper. First, 1jIi amount of resin 6 is placed on the wiring board 3, and then the flip chip 1 is strongly pressed against it and the bump electrodes 2 are made of gold or the like.
By photo-curing or thermally curing the resin 6 with b in good conductive contact with the wiring conductor 5, the conductive contact state is maintained using the shrinkage force and adhesive force of the resin 6 during curing, and the contact portion protected by resin sealing.

[Problem to be solved by the invention]

However, with the above-mentioned conventional method, when trying to increase the number of connection points for Frisobuttons and 7-buttons and narrow the arrangement pitch of bump electrodes accordingly, it is difficult to guarantee the uniformity of the connections, and Positioning becomes difficult.

When the number of bump electrodes on a flip chip exceeds the image side, the maximum variation in bump height increases, so during mounting, the flip chip is pressed against the wiring board with considerable pressure to avoid bumps with large heights. By deforming the electrode, the contact with the wiring conductor is made uniform, but even so, when the warpage of the flip chip and the unevenness of the wiring Ml are combined, the contact with the wiring conductor is incomplete with a bump electrode of small height. If the bump electrode is made of solder, the unevenness that occurs during melting will be considerably reduced, but if the bump electrode is made of gold, etc., the unevenness of the contact pressure will remain until the end as an incomplete connection. In extreme cases, a connection failure occurs in which the bump electrode is not connected to the wiring conductor at all.

As the number of bump electrodes increases, the arrangement pitch becomes narrower accordingly, and when the inner arrangement becomes 5 on or less, it is necessary to suppress the positional deviation between the solid chip and the wiring board during mounting to about 10 nm or less. Conventionally, this positioning was usually done by aligning the outer shape of the solid chip with the mark on the wiring board, but it was necessary to ensure that the misalignment was
In the case of solder bump electrodes, it is not always easy to make the alignment smaller than n.If there is a misalignment in the solder bump electrode, molten solder flows and short circuits between the connection points are likely to occur. It is difficult to reduce the arrangement pitch to 40n or less. In the case of gold bump electrodes, there is no short circuit problem, but misalignment naturally increases the non-uniformity of the connection.

In addition, when the arrangement pitch of bump electrodes is narrow, so-called TA
Method B or inner lead bonding can also be used, but since additional leads and space are required, direct face-down bonding of the flip chip as shown in FIG. 3 is still most advantageous.

The object of the present invention is to provide a mounting device that solves these problems and achieves uniformity of connection and alignment accuracy even when there are many connection points. Our goal is to provide the following.

[Means to solve the problem]

According to the present invention, there is provided a pressurizing means for performing a first-stage operation and a second-stage operation, a pressurizing rod that is movably operated in directions other than the pressurizing direction, and a means for holding a flip chip on its tip surface. a chip pressing mechanism comprising a transparent board holder and a wiring board holding means; an optical means for detecting the position of the flip chip and the wiring board through the board holder; a chip pressing mechanism and a board holding mechanism; The mounting apparatus is provided with a position adjustment means for adjusting the relative position of the holding mechanism, and the flip chip is held on the tip end surface of the pressure rod and the wiring board is held on the board holder, respectively, and the pressure means is operated in the first stage to hold both the flip chips. The positions of the two are detected by optical means while the two are brought close to each other, and the position adjusting means is used to align the two, and then the bump electrode is fixedly connected to the wiring conductor while the pressing means is operated in the second stage. objectives are achieved.

In addition, in order to cause the pressurizing means to perform the first stage operation in the above configuration and the second stage operation with a smaller movement amount, the first stage cylinder and the second stage cylinder with a smaller stroke are combined. It is advantageous to use a pneumatically or hydraulically operated double cylinder mechanism, in which the second stage cylinder is controlled by a pressure regulating valve or the like to increase the operating pressure at a predetermined rate and then maintain it at a predetermined value. is desirable.

The easiest way to connect the pressurizing means and the chip pressurizing mechanism so that they can move in a direction other than the pressurizing direction is to use a flexible connection using, for example, a steel ball. The area of the tip of the pressurizing rod of the chip pressurizing mechanism should be larger than the area of the flip chip, but this tip should be hardened by hardening or attaching high-hardness metal or cemented carbide. It is desirable to maintain uniformity of connection over a long period of time.

As the flip chip holding means of the chip pressurizing mechanism and the wiring board holding means of the substrate holding mechanism, it is simple and highly practical to use, for example, a vacuum suction method.

In the present invention, a transparent substrate is used for the substrate holder of the substrate holding mechanism as described in the above structure, but if the bump electrode of the flip chip is made of gold or the like and an ultraviolet curing resin is used during the mounting, this It is advantageous to use quartz glass with high ultraviolet transmittance for the substrate holder.

It is preferable to use a stereomicroscope with a deep depth of focus as the optical means, and it is advantageous to combine it with a video camera, monitor TV, etc. in order to increase the efficiency of the mounting work, and it is also possible to use a pattern recognition device. This makes it possible to fully automate the mounting process.

As the position adjustment means, an appropriate combination of an x-y operation device or an angle operation device can be used as usual, and by providing this on one side of the chip pressure mechanism and the substrate holding mechanism, the relative position between the two can be adjusted. It is possible to adjust the

Note that the flip chip mounting device of the present invention uses solder,
It can be applied to general mounting of flip chips equipped with bump electrodes of gold, copper, etc.

[Effect]

As described in the configuration in the previous section, the flip chip mounting device according to the present invention! Here, we use a pressurizing means that performs a first-stage operation and a second-stage operation with a smaller amount of movement, and first causes the pressurizing means to perform the first-stage operation, thereby controlling the chip pressure. The flip chip held on the tip of the pressure rod of the mechanism is brought close to the wiring board held on the transparent board holder of the board holding mechanism, and the flip chip is flipped by optical means through the transparent board holder in a state on the verge of mounting. The level of chips and wiring boards! To enable accurate detection of relative positional deviations.

The position adjusting means adjusts the relative position of the chip pressing mechanism and the substrate holding mechanism based on this accurate detection result, and in the present invention, the displacement between the flip chip and the wiring board is 10n or less at the maximum. As a result, the two are precisely aligned, and by operating the pressurizing means in the second stage in this state, the bump electrodes of the flip chip are brought into contact with the wiring conductors of the wiring board.

At this time, the pressurizing rod of the chip pressurizing mechanism that holds the flip chip is operated by this pressurizing means to be movable in directions other than the pressurizing direction, so that the pressurizing means applies pressure during the second stage operation. Even if there is some movement in the lateral direction, the pressurizing rod is not affected by this movement and keeps the bump electrodes of the flip chip in contact with the wiring conductors of the wiring board in the above-mentioned precisely aligned state, and the so-called The bump electrode inside the flip chip can be pressed against the wiring conductor with uniform pressure without causing one-sided pressing.

In such a pressing state, even if the mounting surface of the wiring board is slightly edged, the pressure rod that presses the flip chip onto it can take a corresponding posture. When the chip size is low, it can be suppressed to within a few n, so it can be said that there is virtually no one-sided push of the flip chip.
Note that in this pressed state, the heights of the bump electrodes can be made uniform by deforming the large bump electrodes in the flip chip by, for example, about 20% at most.

The procedure for fixedly connecting the bump electrode and the wiring conductor with this pressurizing means in the second stage operation varies depending on the type of bump electrode, and in the case of gold bumps, the resin is photo-cured or heat-cured while the pressure is applied. In the case of solder bumps, the pressed state is once released, the flip chip and the wiring board are self-aligned as described above using molten solder, and then the solder is preferably solidified by cooling while being pressed again.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the drawings. FIG. 1 shows an example of the configuration of the main parts of the flip-chip mounting apparatus of the present invention for each main operating state.
) to hold the flip chip and the wiring board in their respective predetermined positions, the same figure (b) shows the state of the pressurizing means during the first stage operation, and the same figure (C) shows the state during the second stage operation. shown respectively. Hereinafter, in this embodiment, the flip chip is equipped with a gold bump electrode 2, and its arrangement &l! It is assumed that an ultraviolet curing resin 6 is used for mounting on the substrate 3, and a transparent glass insulating substrate 4 is used for the wiring board 3.

In this embodiment, the pressurizing means 10 shown schematically in the upper part of FIG. Shown as a representative. The pressurizing rod 21 of the chip pressurizing mechanism 20 shown below is guided so as to be movable in the vertical direction of the figure by a position adjustment means 50 shown simply in the figure, and is guided by means such as a spring (not shown). The steel ball 22 in the recess on the upper end surface is biased so as to always contact the lower end surface of the operating rod of the pressure mechanism 10, and receives force from the pressure mechanism 10 only in the downward pressure direction in the figure. It looks like this. In this example of the pressure rod 21, the lower end surface 21a serves as both a pressing surface and a holding surface for the flip chip l, and a suction hole 23 connected to a vacuum pump is provided in the center as a holding means.

Furthermore, in this embodiment, the pressing end surface 21a is hardened to prevent dents from occurring due to the flip chip 1 during long-term use. Note that the above-mentioned position adjusting means 50 uses, for example, position operating devices for the X, y, and θ directions.

The substrate holding mechanism 30 shown at the bottom of FIG.
It is fitted into the recess 32a on the top surface of the i32 so as to protrude very slightly.A plurality of suction holes 33 are wired around the support plate 3 to hold the wiring board 3 on the board holder 31.
The lower side of the second board holder 31 is an opening, and its conical surface is finished into a mirror surface 32b.

A charging head 85 supported by an arm 84 is shown in the center of FIG. 1(a). This head 85 places the flip chip 1 on a seat 86 made of Teflon or the like mounted on its upper surface, and holds the wiring board 3 with suction holes 8 on its lower surface.
0 is loaded into the position shown in the figure while being vacuum-adsorbed by 8.
Next, by moving the head 85 closer to the board holder 31 and cutting off the suction from the suction hole 88, the wiring 1[3 is moved onto the board holder 3I and held there by suction, and that's about it! By bringing the flip chip l close to the pressurizing rod 21 and blowing out compressed air from the blowing hole 87, the flip chip l is moved to the seat 86.
It is floated and transferred to the tip end surface 21a of the pressure rod 21, where it is held by suction.

FIG. 1(b) shows the operation of the pressurizing means 10 in the first stage.As mentioned above, the flip chip l is moved to the pressurizing rod 2
After the wiring board 3 is held on the board holder 31 by the front end surface 21a of the head 85, the head 85 is retracted from the state shown in FIG. Now, after dropping it on the surface of the wiring board 3, pressurizing means 10
By performing the first stage operation to achieve the state shown in the figure, the freesive chip 1 is brought close to the wiring base [3]. At this time, the gap between the tip of the bump electrode 2 and the wiring conductor 5 is sufficiently small, for example, 0.
．． The stroke of the first stage operation of the pressurizing means 10 is set so that the distance is about 5 m.

In this example, since the insulating substrate 4 of the wiring board 3 is transparent, the flip chips L of the wiring board 3 can be seen through the board holder 31, and an optical means 40, which is simply shown in the figure, is used to detect their positions. .

A stereoscopic microscope is suitable for this optical means 40, and by combining this with a video camera, an enlarged image in which images of the wiring board 3 and the flip chip 1 are superimposed can be displayed on a monitor television.

Therefore, in this embodiment, the position of the pressure rod 21 is adjusted by the position adjustment means 50 while viewing this enlarged image, and, for example, the image of each bump electrode 2 is superimposed on the image of the tip of the corresponding wiring conductor 5. , the flip chip l can be precisely aligned with the wiring board 3 so that the mutual displacement is on the order of several microns.

Note that the position adjustment means 50 includes, for example, an X stage and a y stage.
A three-direction position manipulator that combines a stage and a θ stage is used.

FIG. 1(C) shows a state in which the pressurizing means 10 is operated in the second stage. By gradually increasing the pressing force after contact, the large bump electrodes 2 are deformed by up to 20%, and after all the bump electrodes 2 are brought into contact with the corresponding wiring conductors 5, the pressing force is kept constant. . The pressing force of the pressurizing means 10 can be controlled by, for example, supplying working fluid to the cylinder mechanism for second-stage operation.
This can be easily done by inserting a pressure regulating valve or throttle as usual.

At this time, the pressure rod 21 is inserted into the pressure means 1 via the steel ball 22.
Since the pressing force is applied only in the pressing direction from 0, and the stroke of the second stage operation is very small, the bump electrode 2 can be attached to the wiring conductor 5 while being precisely aligned in the state shown in Figure 1 (bl). can be brought into contact.

In addition, in this pressed state after contact, even if the wiring board 3 is somewhat stiff, the pressurizing rod 21 presses the flip chip l against the wiring board 3 in a corresponding posture, so that the tilt between the two is minimized and the pressure rod 21 is pressed against the wiring board 3. The occurrence of pressing defects can be almost completely eliminated.

With the bump electrodes 2 uniformly pressed against the corresponding wiring conductors 5 in this way, a transparent substrate receiver is emitted from the projection head, for example, the tip of an optical fiber, of the light projection means 70 shown briefly in the lower part of the figure in this example. The resin 6 is exposed to ultraviolet rays for a short time through the stand 31 and the insulating base Vi4, and the resin 6 is cured by ultraviolet rays, thereby completing the mounting. Thereafter, the wiring board 3 on which the flip chip 1 has been mounted is taken out from the board holder 31 by means such as vacuum suction using a loading head configured similarly to the loading head 85 shown in FIG. 1(a). Bye.

In addition, when the board holder 31 is quartz glass and the insulating substrate 4 of the wiring board 3 is made of Pyrex, a transmittance of about 80% or more is obtained for ultraviolet rays with a wavelength of 365 na, and the transmittance is 250 to 3001 + 111/cj to the resin 6. It is possible to irradiate ultraviolet rays with an intensity of . At this time, the mirror surface 32b of the support plate 32 below the substrate holder 31 serves to effectively utilize the scattered ultraviolet rays.

FIG. 2 illustrates the overall configuration of the device of the present invention, of which only the main parts were shown in FIG. 1. FIG. 2(a) is a front view thereof, and FIG. 1 A side view is shown in FIG. 1 (C).

The main parts explained in FIG. 1 are shown in the center of the upper part of FIG. 2(a). The pressurizing means IO consists of a first stage cylinder mechanism 11 and a second stage cylinder mechanism 12 connected in series, and the strokes of these are, for example, 50 strokes for the former and 0 strokes for the latter.
It is said to be ゜5■. This pressurizing means 10 is mounted together with a position operating device 52 on a movable base 51 of a position adjusting means 50 as shown in FIG. to apply pressure.

As shown in the same figure (C1), the support plate 32 of the substrate holding mechanism 30 is firmly attached to a frame etc. via a plurality of legs, and the optical means 40 is wired under it.Optical means 40 Stereo microscope 41 is supported on a column 44 whose position is controlled by a position control device 43 on a movable table 42, and its field of view can be finely adjusted by the position control device 43.The stereo microscope 41 is preferably one with a coaxial illumination and a magnification of about several dozen. A video camera is combined with this, and its field of view is similar to that shown in the figure (Tape's Monitor TV 4).
5 is displayed as the image above. This monitor television 45 is combined with an X stage and a y stage for the zero position operating device 43, which is preferably one with a horizontal resolution of 400 to 500 lines, similar to a video camera.

Resin supply system 60 above the monitor television 45 in FIG.
The dispenser 61 dispenses the above-mentioned ultraviolet curable resin at 0.
It can be supplied in minute amounts with an accuracy of about 1 g, and is connected via a flexible hose 62 to a capillary-shaped resin supply nozzle 63 supported on the position operating device 52. The cylinder 64 operates the nozzle 63 via the movable base 51 to the resin supply position.

The ultraviolet rays 1 of the light projection system 70 shown in the lower right of the same figure (al.
The ultraviolet light generated by 1171 is sent via optical fiber 72 to projection head 73 carried by stereomicroscope 41 . A cylinder 74 is also provided for this light projection system 70, so that the projection radar 73 can be operated to the projection position via the movable table 42.

A robot 80 is provided for operating the aforementioned loading head 85 for loading flip chips and wiring boards into mounting positions. As shown in FIG. 8B, this robot 80 uses an X-direction manipulator 81 and a Y-direction manipulator 82 to operate a manipulating head 83 that supports a charging head 85 via the aforementioned arm 84.
The position of is operated by program control. As previously explained in FIG. 1, an arm 84 is inserted into the operation head 83 and is operated slightly in the vertical direction so as to bring the charging head 85 closer to the lower end surface 21a of the pressure rod 21 or the substrate holder 31. A simple mechanism is incorporated.

Further, a vacuum system 9o consisting of a vacuum pump 91 and a drive motor 92 is attached to the apparatus of the present invention for suctioning flip chips and wiring boards.

In addition, the operation of each part in the device of the present invention is sequence fIiI! A program control device 100 that controls the device and an operation control bag ztoi that controls or operates various parts in the device according to instructions from the program control device 100 are incorporated.

An example of a flip-chip mounting procedure performed under the control of this program control device 1000 will be described in sequence as follows.

(11) First, with the loading head 85 placed at a predetermined position outside the mounting position, the flip chip is placed on top of it by equipment (not shown) or by hand, and then the loading head 85 is moved by the robot 80 as shown in FIG. 2(a). The board tray 7 is placed on a suitable table as shown in FIG.

[2] The robot 80 moves the charging head 85 to the 11th ff.
l (Move to the al position and operate it with Rad8
3, move the flip chip 1 to the lower end surface 21a of the pressure rod 21 and the wiring board 3 onto the board holder 31 and hold them, respectively, while operating the flip chip 1 slightly in the up and down direction according to the procedure described above.

(3) Move the charging head 85 to the original position!
After returning to the position, the cylinder 64 is energized to move the nozzle 63 onto the wiring base Fi, 3, and then the dispenser 61
Then, a minute amount of resin 6 of about several grams set in advance is dropped onto the wiring board 3.

(4) Operate the pressurizing means 10 in the first stage to the state shown in FIG. The flip chip l is aligned with the wiring board 2 until the deviation is 10n or less.

(5) After operating the pressurizing means lO in the second stage to bring the state shown in FIG. 73 is placed at the projection position, the ultraviolet rays from the ultraviolet source 71 are applied to the resin 6.
Usually, it is irradiated for several tens of seconds to cure it.

(6) Since the mounting is completed above, the wiring board 3 on which the flip chip l is mounted can be taken out from the mounting position by an appropriate means (not shown), and the same operation can be repeated thereafter.

Although the positioning in step (4) in the above-mentioned procedure in this embodiment requires human effort, the video signal captured by the stereomicroscope 41 is fed to a computer that performs a pattern recognition operation, and the position control device 52 is controlled by the computer. The entire procedure can be fully automated.

The flip chip mounted by the mounting apparatus according to the present invention described above has no appreciable inclination between it and the wiring board, and even if the chip before mounting is slightly warped, the difference between the bump electrode and the wiring conductor is There is little variation in contact resistance, and the maximum variation is 2 even when the number of bump electrodes is 100 or more.
It is 0% or less.

Furthermore, the uniformity of contact can be maintained over a long period of time while the mounted product is in use.

In order to guarantee such uniform contact or connection, it is necessary to maintain the flatness of the lower surface of the pressure rod and the surface of the substrate pedestal, especially the former, to submicron precision. However, the mounting apparatus according to the present invention can maintain the flatness of the pressing surface for a long period of time.

The flip chip mounting apparatus according to the present invention is applicable to mounting flip chips that have 100 or more bump electrodes each having a size of 10 to 50 μ square and an arrangement pitch of 20 to 100 nm, and the alignment accuracy with the wiring board is 10 nm. The following,
The slope with that can be guaranteed to be 3n or less for a chip of 10 squares.

The present invention is not limited to the embodiments described above, and the present invention can be implemented in various embodiments. In the embodiment, the bump electrodes are made of gold, but bump electrodes of copper or solder can also be used. Furthermore, the insulating substrate of the wiring board does not necessarily have to be transparent, and the present invention can be carried out within its gist by appropriately changing the steps of mounting work. The overall specific configuration shown in FIG. 2 is merely an example, and various practical configurations and forms can be given to it in accordance with the type of bump electrode, the demand for automation of mounting work, etc. The same applies to the specific procedures and conditions of the mounting work, and various modifications or selections can be made depending on necessity or circumstances.

〔Effect of the invention〕

As explained above, in the present invention, for a flip-chip mounting apparatus, the first stage operation and the second stage operation with a smaller movement amount are provided.
A chip pressurizing mechanism includes a pressurizing means that performs a stepped operation, a pressurizing rod that is movably operated in directions other than the pressurizing direction, a means for holding a flip chip on its tip surface, and a transparent substrate holder. A board holding mechanism comprising a stand and a means for holding the wiring board; an optical means for detecting the position of the flip-chip and the wiring board through the board holder; and a position adjustment means for adjusting the relative position of the chip pressing mechanism and the board holding mechanism. A flip chip is mounted on the tip of the pressure rod to hold the wiring board on the board holder, and the pressure means is operated in the first stage to bring the two close together, and the position of both is detected by optical means. The problems of the prior art can be solved by aligning the bump electrodes with the wiring conductor while adjusting the position using the position adjusting means, and then operating the pressurizing means in the second stage to firmly connect the bump electrodes to the wiring conductors. , the following effects can be achieved.

(a) First, the pressurizing means is operated in the first stage, and the relative position of the flip chip and the wiring board is measured by optical means through a transparent board holder in a state where the flip chip is brought close to the wiring board and is about to be mounted. Based on this detection, both can be accurately aligned by the position adjustment means.

(bl After this positioning, when the pressing means is operated in the second stage to bring the bump electrodes of the flip chip into contact with the wiring conductors of the wiring board, the pressing rod holding the flip chip is moved in a direction other than the pressing direction by the pressing means. is operated in a mobile manner,
Even if the pressurizing means moves slightly in a direction that causes misalignment, the pressurizing rod will not be affected by this, and the second stage movement is very short, so the bump electrode can be handled while remaining precisely aligned. It is possible to accurately contact the wiring conductor.

Due to the effects of (a) and (bl), the present invention can reduce the misalignment between the flip chip and the wiring board to less than LOn at the maximum.
Furthermore, by using image processing and pattern recognition technology, 5n
It can be kept below.

(C) When applying pressure for mounting after bringing the bump electrode into contact with the wiring conductor, even if there are causes of uneven connection such as warpage of the flip chip or inclination of the wiring board surface, the pressure rod may move in a direction other than the pressing direction. Since the flip chip is pressed against the wiring board in a freely movable and bent position according to the bending factor, a large number of bump electrodes are evenly fixed to the wiring conductor while effectively preventing problems such as so-called one-sided pressing. Can be connected. As a result, the tilt of the mounting posture of the flip chip with respect to the wiring board can be suppressed to within several nanometers even when the chip size is 10 m square, and when a flip chip with n or more gold bump electrodes is mounted using resin adhesive strength. However, the variation in contact resistance between the bump electrode and the wiring conductor can be suppressed to within 20%, and the uniformity of this contact can be maintained over a long period of time during use of the mounted product.

These features of the present invention are particularly useful for mounting flip chips with multiple connection points in which small bump electrodes with a size of several tens of microns are arranged at a narrow pitch. This can contribute to improving trustworthiness.

[Brief explanation of drawings]

The figures all relate to the present invention; FIG. 1 is a sectional view showing an example of the configuration of the main parts of the flip-chip mounting device according to the present invention in each main operating state, and FIG. 2 is a front view illustrating the overall configuration of the device of the present invention. Figure, partial top view. FIG. 3 is a side view showing how to mount a flip chip on a wiring board. In these figures, l: flip chip, 2: bump electric bridge, 2a: solder bump electric bridge, 2b: gold bump electric bridge, 3: wiring board, 4: insulating substrate, 5: wiring conductor, 6: resin, 7 ;Substrate tray, I
O: Pressure means, 11 1st stage cylinder mechanism, 12: 2nd stage cylinder mechanism, 20: Chip pressure mechanism, 21: Pressure rod, 21a: Tip surface of pressure rod, 22: Steel ball, 23:
Suction hole as holding means for flip chip, 30: Board holding mechanism, 31: Board holder, 32: Support plate, 32a; Recess, 32b: Mirror surface, 33: Suction hole as holding means for wiring board, 40: Optical means, 41: Stereo microscope, 42: Movable base, 43: Position operation device, 44: Support column, 45: Monitor TV, 50: Position adjustment means, 51: Movable base, 52: Position adjustment machine, 60: Resin supply system , 61: Dispensa, 62
: Hose, 63: Resin supply nozzle, 64: Cylinder for nozzle position operation, 70: Light projection system, 71: Ultraviolet source, 72
: optical fiber, 73: projection head, 74: cylinder for head position operation, 80: robot, 81: x-direction operating device,
82: Y direction operating device, 83: Operating head, 84: Arm, 858 Charging head, 86: Flip chip catch, 8
7: Air blowout hole, 88: Adsorption hole, 90: Vacuum system, 91:
Vacuum pump, 92: Drive motor, 100 Nibragram control device, 101: Operation diagram

Claims (1)

[Claims] A pressurizing means that performs a first-stage operation and a second-stage operation with a smaller amount of movement, a pressurizing rod that is movably operated in directions other than the pressurizing direction, and a flip chip held on its tip surface. a chip pressing mechanism comprising a means for pressing the flip chip, a substrate holding mechanism comprising a transparent substrate holder and a means for holding the wiring board thereon, an optical means for detecting the position of the flip chip and the wiring board through the substrate holder, and a chip A pressurizing mechanism and a position adjusting means capable of adjusting the position of one of the substrate holding mechanisms relative to the other are provided, and the flip chip is held on the tip surface of the pressurizing rod and the wiring board is held on the substrate holder, and the pressurizing means is provided. The first stage is operated and the two are brought close to each other, and the positions of the two are detected by optical means and the position adjusting means is used to align them.The second stage of the pressurizing means is operated and the bump electrodes of the flip chip are wired. A flip chip mounting device that makes a fixed connection to the wiring conductor of the board.