JP2001015536A - Method for bonding bump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a bump at a correct position in an IC pattern on a wafer by searching a first recognition position, registering the obtained position as a data automatically, and executing a mark recognition according to the registered positional data. SOLUTION: When a wafer 1 held by a bonding stage 20 is subject to bump bonding, a bonding head 11 recognizes marks given in advance at the specified positions on the wafer 1, with camera units 40A and 40B, and judges correct bump bonding positions according to the recognized positional data and executes successively bump bonding to the wafer 1. In addition, in the case where the bonding head 11 does not recognize a first mark at a first halt position above the wafer 1, it continues searching automatically until it recognizes the first mark, and registers the position of the obtained first recognition mark as a data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera unit capable of recognizing the position of an IC chip to be bonded. The camera unit uses a bonding head arranged above a bonding operation mechanism to electrically connect to an electrode portion of the IC chip. The present invention relates to a bump bonding method for forming a bump by a wire bonding technique, and more particularly to a bump bonding method for forming a bump in a state of a wafer before being divided into IC chips.

[0002]

2. Description of the Related Art In recent years, in particular, focusing on portable devices,
Various electronic devices are required to be further reduced in size and weight, and accordingly, ICs built in these electronic devices are required.
Chips are also significantly reduced in size. In connection with this, for example, when a bump is provided on an electrode portion of an IC chip, a bump bonding method of forming a bump on each IC chip in a state of a wafer before the IC chips are separated into individual ones by dicing is known. Are known. However, when bumps are directly formed on a wafer in such a wafer state, there are various technical problems as described below, and it is necessary to solve these problems in practical use.

[0003]

For example, between wafers of different production lots (that is, crystal materials before being sliced), there is usually an outer diameter tolerance of the wafer or an IC to the wafer.
There is a difference in the position of the recognition mark provided corresponding to each IC chip on the wafer due to the displacement of the IC pattern at the time of patterning, and the position of the first recognition mark may be changed at the time of bump bonding depending on the wafer. Sometimes it cannot be detected. Conventionally, to cope with this, the operator manually corrects the recognition teaching position every time the production lot changes, resulting in a decrease in production efficiency.

In the conventional bump bonding method, position recognition and bonding are usually performed in the minimum unit of an IC chip set on a wafer. In this case, however, the IC chip is mounted on a target wafer. Recognition times are required for each IC (for example, 2 ICs per IC).
If one mark is attached and a recognition time of 0.2 second is required for one mark, the total recognition time is 0.2 seconds × the number of marks 2 × the number of ICs. It was quite long and productivity was poor.

Further, in the conventional bump bonding method, a mark recognizing camera equipped with an expensive zoom lens is required in order to cope with a positional change due to various sizes of the IC chip and the butt mark. Was bringing.

[0006] By the way, bump bonding to a wafer is performed while the wafer is fixed on a heating stage.
The tip of the bonding wire is positioned above the bonding target electrode of the IC chip on the wafer, and the tip of the wire is melted to apply ultrasonic vibration to the ball formed using the horn of the bonding head. This bonding is performed by thermocompression bonding of the ball to the electrode portion.As a bonding head for performing such bonding, conventionally, generally, a bonding wire clamper is located above a capillary provided at the tip of an ultrasonic horn,
A camera unit having a recognition camera and a lens barrel for the camera is disposed above the clamper. In a bonding head having such a structure, the lens barrel and the ultrasonic horn of the mark recognition camera thermally expand due to the thermal effect of the wafer heating stage, and the center of the capillary through which a wire is inserted through the center and the end of the camera. The camera offset value, which is the distance between the two, may change. In the past, in order to deal with this problem, it was necessary to frequently measure the deviation manually and adjust the camera offset frequently, so that the work efficiency was poor and the offset value was the cause of the defect. Met.

The present invention has been made in view of the various technical problems described above, and provides a bump bonding method for easily and quickly forming a bump at an appropriate position with respect to an IC pattern on a wafer. The purpose is to do.

[0008]

According to a first aspect of the present invention, a camera unit capable of recognizing a position of an IC chip to be bonded is arranged above a bonding operation mechanism. In the bump bonding method of forming bumps on a wafer on a bonding stage using the bonding head, the camera unit can recognize a mark to be recognized at a first recognition point above the wafer. If there is no mark, a first recognition position at which the first mark can be recognized is searched, and after searching for the first recognition position, the position is automatically registered as data. A step of performing recognition.

[0009] By performing bump bonding in this manner, even for wafers of different production lots, there is no need for the operator to perform position correction, and the machine automatically performs the position correction, so that the production efficiency can be improved.

Further, the invention according to claim 2 of the present application (hereinafter referred to as “the invention”)
According to a second aspect of the present invention, a camera unit capable of recognizing the position of an IC chip to be bonded is provided using a bonding head disposed above a bonding operation mechanism.
In a bump bonding method for forming a bump on a wafer on a bonding stage, position recognition of an IC chip and bump bonding are performed in a block unit composed of a plurality of IC chips on a predetermined region on the wafer. It was done.

In this case, the number of times of position recognition on the wafer can be reduced, and re-bonding to the bump-bonded IC chip can be prevented.

Further, the invention according to claim 3 of the present application (hereinafter referred to as “the invention”)
According to a third aspect of the present invention, a camera unit capable of recognizing the position of an IC chip to be bonded is provided using a bonding head arranged above a bonding operation mechanism.
In a bump bonding method for forming a bump on a wafer on a bonding stage, a bat mark teaching function is provided so that a butt mark position with respect to a recognition mark position is input in advance and determined.

In this case, an expensive recognizing camera with a zoom lens is not required, and equipment costs can be reduced.

Further, the invention according to claim 4 of the present application (hereinafter, referred to as a third invention) is characterized in that
In a bump bonding method in which a camera unit capable of recognizing the position of a C chip forms a bump on a wafer on a bonding stage by using a bonding head arranged above a bonding operation mechanism, the center of a bump bonded immediately before is formed. , And the difference from the NC data is automatically corrected for the camera offset value.

By employing such a bump bonding method, it is possible to automatically correct the displacement of the camera unit due to the thermal deformation of the camera barrel and the horn, thereby suppressing the occurrence of defects.

[0016]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, in FIG.
1 schematically shows the overall arrangement of a bump bonding apparatus according to an embodiment of the present invention. This bump bonding apparatus is intended for bonding a wafer 1 having an origin flat (hereinafter, referred to as an orientation flat) having a disk shape and having an outer peripheral portion cut linearly so as to specify the directionality of a crystal. It is. In the bump bonding apparatus 10, as a main configuration for forming bumps on each IC chip in a state of a wafer before the IC chips are individually separated by dicing, a loading station 2 into which a carrier containing the wafer 1 is loaded. A transfer station 3 on the carry-in side where the wafer 1 drawn from the carrier is positioned, a bonding station 4 for forming the bumps, and a transfer station 5 on the carry-out side where the wafers 1 with the bumps formed are positioned; An unloading station 6 for sequentially accommodating the bumped wafers 1 in a carrier and unloading them is arranged at regular intervals on the line. At the front of the wafer 1 transfer line, there are provided unloading means 7 for taking out the wafer 1 from the loading station 2 to the loading transfer station 3 and insertion means for inserting the wafer 1 from the unloading transfer station 5 to the unloading station 6. 8 are provided. Further, a transfer means 9 for transferring the wafer 1 from the loading-side transfer station 3 to the bonding station 4 and transferring the wafer 1 from the bonding station 4 to the unloading-side transfer station 5 is provided at the front thereof. I have.

The bonding station 4 is provided with a bonding stage 20 composed of a heat stage for bonding by ultrasonic thermocompression bonding, and a bonding head 11 is provided at a rear portion thereof. The bonding head 11 is supported so as to be movable in two directions, XY, and is moved to arbitrary positions in the X and Y directions by an X-axis motor 12a and a Y-axis motor 12b.
It is mounted on a positionable XY table 12.

FIG. 2 is a perspective view of the bonding head 11. The bonding head 11 has a clamper 18 for gripping a wire, a capillary 22a at the tip of which a wire is inserted, a horn 22 for applying ultrasonic vibration to a formed bump ball 14a (see FIG. 3), and a discharge And a torch 23 for use. In the bonding operation mechanism 15, a clamper 18 of the bonding wire 14 is located above a capillary 22a provided at the tip of the ultrasonic horn 22, and a recognition camera 24 and the camera A camera unit 40 provided with a lens barrel 41 is disposed. The recognition camera 24 is for performing recognition of an IC chip to be bonded and visual recognition of a bonding operation.
At the tip of the lens barrel 41, an IC chip to be recognized and a prism 42 which projects the bonding work and projects light onto the recognition camera 24 side are attached. In the bump bonding apparatus 10 according to the present embodiment, an image recognized by the camera unit 40 is displayed on a recognition monitor (not shown), and a recognition signal is input to a data processing apparatus (not shown) to input data. It is configured to process. Further, a coaxial illumination unit 43 for transmitting illumination light for illuminating an object at the time of recognition by the camera is connected to a middle portion of the lens barrel 41.

A bonding head 1 having such a configuration
3 will be described with reference to FIG. 3. Whenever the bonding head 11 moves to a position where the wire 14 is sent out through the capillary 22a and faces the predetermined electrode pad 27 of the wafer 1, the torch 23 is used. The tip portion is melted by the spark current to form the ball 14a as shown in FIG. The position of the wire 14 facing each electrode pad 27 is controlled with high accuracy based on the visual recognition of the recognition camera 24.
The formed ball 14a is bonded on the electrode pad 27 of the wafer 1 by thermocompression bonding and ultrasonic vibration as shown in FIG. 3B. Crimping force in this case is 30 g to 5 g
The ultrasonic vibration is preferably applied in the horizontal direction, with an amplitude of about 0.5 μm and a frequency of about 60 to 70 KHZ (specifically, about 63.5 KHZ). Next, the wire 14 is cut by the upward movement of the clamper 18 and the capillary 22a holding the wire 14 as shown in FIG. 3C, and the ball 14a is placed on the electrode pad 27, and 30 μm to 40 μm from the ball 14a. A bump 28 having a projecting length of about 60 μm and a wire portion 14b projecting to a height of about 60 μm is formed. Wire 14
For the cutting, a material having a high Young's modulus and a low thermal conductivity is used so that the above-described cutting process is reliably performed at a predetermined position.

Next, the bonding stage 20 capable of holding the wafer 1 will be described with reference to FIG. The bonding stage 20 includes a stage plate 91 and a heat block 92 below the stage plate 91. On the upper surface of the stage plate 91, regulating roller pairs 93A are provided on both sides so that the wafer 1 can be fitted with a margin. ,
93B is provided. Also, the stage plate 91
Regulating portions 95A, 95 having a pair of contact rollers 94A, 94B engaged with the orientation flat 1a of the wafer 1.
B, for example, the regulating roller pair 93B, 93A located on opposite sides such that the regulating portion 95A presses the wafer 1 against the regulating roller 93B.
The position of the wafer 1 is regulated in cooperation with the above. These restricting portions 95A and 95B are constantly urged in a restricting direction by a spring 96, and are arbitrarily moved and driven in a restricting releasing direction by a cylinder (not shown) arranged on the back side of the stage plate 91. .

The stage plate 91 has a suction / floating air port 101 for sucking and floating the wafer 1.
A swirling air jet 102 which is opened obliquely in the same direction in the circumferential direction so as to swivel the wafer 1;
The wafer 1 is moved to one of the regulating roller pairs 93A or 93B so that the wafer 1 in the swirling state does not wobble and fluctuate.
First and second biasing air jets 103 to stop against
A, 103B. The air supply to the first and second bias air outlets 103A and 103B is valve-controlled, and can be switched by a predetermined switching means (not shown). The first and second offset air jets 103A
And 103B are arranged inside the radius of the swirling airflow so as not to interfere with the swirling airflow spouted from the swirling air outlet 102, and the suction / floating air port 101 is located outside the radius of the swirling airflow. It is located inside and inside.

In the heat block 92, 6
The cartridge heaters 105 are inserted in parallel, and three thermocouples 106 respectively corresponding to the two heaters 105 are buried, and the temperature of the heat block 92 is controlled (in the present embodiment, a temperature up to about 300 ° C.). Control) is performed by three systems. The heat block 92 is supported by a pair of left and right leg members 107 having high heat dissipation.

In the bump bonding step using the bonding stage 20, when the wafer 1 is transferred by the transfer means 9 to the inside of the pair of control rollers 93A and 93B on the bonding stage 20, the control section 95B is controlled. By operating, the contact roller 94B
Is engaged with the orientation flat 1a, and the wafer 1 is
Pressed against 3A side. At the same time, air is blown out from the first offset air jet 103A to the wafer 1,
The wafer 1 is urged against the pair of regulating rollers 93B. As a result, the position of the wafer 1 is regulated by the contact roller 94B and the regulating roller pair 93A. In this state,
The wafer 1 is sucked and fixed by the sucking action of the floating / air port 101, and bumps are formed on IC chips in a half area thereof.

Next, the suction and regulation portion 95B of the wafer 1
The wafer 1 floats by blowing air from the suction / floating air port 101, and the air is blown out from the second offset air jet 103B to attach the wafer 1 to the regulating roller pair 93A side. In this state, a predetermined flow rate of air is blown out of the swirling air jet 102 while the wafer 1 is being swung, whereby the wafer 1 turns. In this manner, the wafer 1 is swung in the rotating state and
By urging the wafer 1 against 3A, the wafer 1 can be swung at a fixed position without whirling.

Subsequently, the regulating section 95A regulates,
The contact roller 94A is engaged with the orientation flat 1a so that the wafer 1
Of the wafer 1 against the regulating roller pair 93B, the position of the wafer 1 is regulated. Then, after the wafer 1 is suction-fixed by the suction action at the suction / floating air port 101, bumps are formed on the IC chips in the remaining half area by the bonding head 11.
Is completed on the entire surface of the substrate. As described above, when the bumps are formed on the wafer 1 in half regions at a time, the moving range of the bonding head 11 becomes small. Therefore, it is necessary to secure the rigidity and dimensional accuracy of the bonding head 11 and realize high-precision bump formation. Can be.

When bump bonding is performed on the wafer 1 held on the bonding stage 20 as described above, the bonding head 11 recognizes a mark previously given at a predetermined position on the wafer 1 by the camera unit 40, The bump bonding is sequentially performed on the wafer 1 while determining an appropriate bump bonding position based on the position data obtained thereby. In the bump bonding apparatus 10, as in the conventional technique, the bonding head 11 is used to cope with a difference in the position of the recognition mark between wafers of different production lots (crystal materials before being sliced into a wafer). Each time the production lot changes, the position of the first mark recognition position needs to be corrected, but in this embodiment, the bonding head 11 cannot recognize the first mark at the first stop position above the wafer. Can be automatically searched until the first mark is recognized, the position of the first recognized mark searched can be registered as data, and subsequent mark recognition is performed based on the position data. It has become.

The automatic search process of the recognition mark will be specifically described. In FIG. 5, only a small number of IC chips set on the wafer 1 are shown, and other IC chips are omitted. In each IC chip, a recognition mark M (shown by a white plus) is provided near a corner of the chip on a diagonal line. A frame indicated by a solid line indicates a recognition area A1 projected on a display monitor via the recognition camera 24 of the bonding head 11, and a frame indicated by a virtual line inside the frame indicates the position of the recognition mark M. This represents the detection area A2. An aiming mark S is provided at the center of these two regions.

If the target recognition mark M cannot be detected at the first recognition point on the wafer 1 by the recognition camera 24, the bonding head 11 moves to search for the first recognition position of the wafer 1. . At this time, based on the preset search area, the bonding head 11 first moves by a predetermined width (width corresponding to the horizontal width of the search area) in the positive and negative directions of X. After the movement, it returns to the original position. Next, it moves by about 1/3 of the vertical width of the recognition area A1 in the negative direction of Y. Then, the Y coordinate is moved in the positive / negative direction of X with the width corresponding to the horizontal width of the search area as described above, without changing the Y coordinate. Thereafter, the bonding head 11 similarly moves in the positive and negative X directions each time it moves in the negative Y direction.

When the movement in the negative direction of Y is completed, the bonding head 11 moves in the positive direction of Y, and every time it moves, the bonding head 11 moves in the positive and negative directions of X in the same manner as in the case of moving in the negative direction of Y. The search area A2 is moved by a width corresponding to the horizontal width.
During the movement of the bonding head 11, the mark M
Is recognized, the position of the mark M is immediately registered as data. After registering the position data, bump bonding is performed while sequentially recognizing the mark M based on the position data.

In the bump bonding apparatus according to this embodiment, as described above, first, half of the area on the wafer is bonded, and then the wafer is rotated halfway on the bonding stage, and the other half is rotated. As shown in FIG. 5, first, the first search is performed with the orientation flat 1a on the left side, and the position of the recognition mark M is corrected, so that the wafer 1 is rotated by half a turn. When performing bump bonding with the orientation flat 1a positioned on the right side, it is not necessary to perform a search again, and the recognition start position can be corrected by converting from the offset value obtained by the previous position correction. As described above, by automatically retrieving the recognition start position of the IC chip arranged on the wafer and registering the data, the position of the bonding head 11 is corrected more quickly than in the conventional case where the position is corrected manually. Bump bonding can be performed.

Next, when bump bonding is performed on the wafer 1 held on the bonding stage 20,
A method of performing recognition and bonding in units of blocks each including a predetermined number of IC chips (a so-called block bonding method) will be described. FIG. 6 is a plan view showing one half of the wafer 1. On the upper surface of the wafer 1, a plurality of IC chips 1c are set. In this embodiment, the I set inside the wafer 1 (inside the thick frame in FIG. 6)
The C chip is recognized and bonded in a block unit composed of a predetermined number of IC chips. On the other hand, an IC set on the periphery of the wafer (outside the thick frame in FIG. 6)
For chips, as is generally known in the prior art,
Recognition and bonding are performed on a chip-by-chip basis.

In this block bonding method, as shown in FIG. 7, the IC chips set on the inside of the wafer 1 (the inside of the thick frame in FIG. 6) are one block for each 3 × 4 IC chip (reference numeral 1B). ). In this case, the bonding head 11 above the wafer 1 is controlled to move in the direction of arrow d1 so as to sequentially perform processing on each block 1B.
In this embodiment, the bonding head 11
While judging the IC chip and the bump-bonded block on the peripheral edge of the wafer, the wafer is inverted and shifted one step upward.

When the recognition and the bonding in the block unit are completed, the wafer 1 is continuously moved as shown in FIG.
Recognition and bonding are started for the IC chip on the periphery of. Here, first, the center in the X direction is determined based on data input in advance. The bonding head is controlled to move in the direction of arrow d2 so as to sequentially perform processing on each IC chip 1c with reference to the center in the X direction.
That is, in this embodiment, the bonding head 1 is determined while judging the bump-bonded IC chip.
When 1 is on the left side of the center in the X direction, it is inverted and 1
When the bonding head 11 is shifted to the upper side of the step, and the bonding head 11 is on the right side of the center in the X direction,
It moves so as to be inverted and shifted one step downward.

In recognition and bonding in units of IC chips, first and second recognition in units of target IC chips or blocks are performed in order to prevent bonding to the outside of the wafer 1 on the bonding stage 20. The bonding is performed only when the electrode pad for forming the mark and the bump is detected on the wafer 1.
Then, when these cannot be detected, the head 11 is inverted in the X direction and shifted one step upward or downward. As described above, by performing the position recognition of the IC chip and the bump bonding on the specific area on the wafer 1 in units of blocks, the number of times of position recognition can be reduced, and the bonding operation can be speeded up. .

Further, in the bump bonding apparatus 10 according to the present embodiment, by providing the butt mark teaching function, the bat mark position with respect to the recognition mark position can be input by teaching in advance and discriminated. FIG. 9 is an enlarged plan view showing an IC chip 1c having a butt mark. Each IC chip 1c on the wafer 1 is provided with a bat mark 30 at a predetermined position on each IC chip 1c as can be seen from FIG. This butt mark 30 is, in principle, at the center C of the IC chip 1c.
Are attached to positions separated by X and Y in the X and Y directions (that is, coordinates (X, Y) if the center C is the origin). The recognition camera 24 (see FIG. 2)
Recognition is performed on the chip 1c at the position of the coordinates (X, Y).

FIG. 10 shows an example of the recognition window W obtained by the recognition camera 24. In this embodiment, when the size of the bat mark 30 is smaller than the recognition window W, whether or not the bat mark 30 has a shape is recognized and determined. On the other hand, if the bat mark 30 deviates from the recognition window W,
If it is larger than the whole area of the recognition window W,
It is determined what percentage of the area occupied by the bat mark 30 is or more.

As described above, by providing the butt mark teaching function, the position of the bat mark with respect to the recognition mark position can be input by teaching in advance and discriminated. Therefore, a conventional recognition camera with a zoom lens is not required, and the conventional camera can be used. Mark recognition can be performed using a recognition camera, and as a result, equipment costs can be reduced. In addition, if the position of the electrode pad on the IC chip is taught by using such a function, it is possible to determine whether or not each IC chip has been bump-bonded. Thus, it is possible to prevent the bonding of the bump-bonded IC chip again.

Further, in the bump bonding apparatus 10 according to the present embodiment, although not particularly shown, the center of the previously bonded bump is recognized, and the difference from the bonding center based on the NC data is used as the offset value of the camera. It is automatically corrected for this. Such automatic correction is performed using a plurality of points (a plurality of bump centers) as samples. That is, the shifts at a plurality of points are averaged, and the subsequent bump bonding positions are corrected. In this case, the upper limit or the lower limit of the outer diameter of the bump is set in advance, and the bump outside the upper or lower limit is not taken into consideration. The correction timing of the camera offset is performed when thermal deformation of the camera lens barrel and the horn becomes large, or after the recognition of a predetermined number of chips. In this way, by automatically correcting the displacement of the camera unit, the occurrence of defects can be suppressed, and
It is not necessary to manually adjust the camera offset as in the related art, and the work efficiency can be improved.

Hereinafter, a flow of bump bonding to a wafer on a bonding stage accompanied by correction of each bonding position data described above will be described with reference to the flowcharts of FIGS. In FIG. 11, when the wafer 1 is transferred onto the bonding stage 20, first, step 1 (hereinafter, step is described as S)
In step 1, the orientation flat direction is confirmed, and if the orientation flat 1a is facing left, the process proceeds to S2, where a first search is performed. If the orientation flat 1a is facing right in S1, the process proceeds to S11, and the wafer 1 is inverted. Then, S
At 12, it is determined whether or not the first search data is corrected. If YES, the process proceeds to S13, and after correcting the first bonding recognition position, the process proceeds to S5.

In the first search (S2 to S4), first, in S2, it is determined whether or not to perform the first search. If YES, the process proceeds to S3 to perform the first search. For example, changing the production lot of wafers,
When processing the first wafer, a first search is performed. In S4, an area search is sequentially performed, and when the data obtained by the search is different from the previous data, automatic update registration is performed. If NO in S2, the process proceeds to S5. Following the first search, S
At 5 and S6, the first mark and the second mark (reference numeral M in FIG. 5) are respectively recognized.

Following the recognition of the mark position, in S7, it is determined whether or not to determine whether bump bonding has been completed. If YES, the flow advances to S8 to determine whether or not bump bonding has been completed. If NO in S7, the process proceeds to S14 (see FIG. 12). Y in S8
If it is ES, the process proceeds to S9, where block bonding is designated and it is determined whether bonding has been completed for each IC chip. If YES in this S9,
Proceeding to S10, the bonding route is changed (see FIGS. 7 and 8). After the change of the bonding route in S10, the process returns to S5 to process the next IC, and the subsequent flow is repeated. If NO in S8, the process proceeds to S16 (see FIG. 12). Further, if NO in S9, the process skips one IC and returns to S5, and repeats the subsequent flow.

As can be seen from FIG. 12, in S14, it is determined whether or not to perform bat mark detection. If YES in S14, the process proceeds to S15, and it is determined whether there is a bat mark. If YES in S15, one IC is skipped and the process returns to S5, and the subsequent flow is repeated. If NO in S14 and S15, both proceed to S16 (see FIG. 12). In S16,
It is determined whether there is previous calibration data. If YES in S16, the process advances to S17 to average the multiple-point auto-calibration data. If NO in S16, S1
Proceed to 8. In S18, bump bonding is performed, and subsequently, in S19, it is determined whether or not data acquisition for auto calibration is POS. If YES in step S19, the process advances to step S20 to acquire auto calibration data. In S19, NO
If it is, the process proceeds to S21.

In S21, it is determined whether or not the bonding in units of IC chips or blocks has been completed. If YES in S21, the process proceeds to S22, and if NO, the process returns to S18 and the subsequent flow is repeated. In S22, it is determined whether the bonding in the bonding area has been completed. If YES in S22, the process proceeds to S23, and if NO, the process returns to S5 (see FIG. 11), and the flow thereafter is repeated. In S23, it is determined whether the wafer is double-sided or single-sided. If it is both sides, the wafer bonding is completed. If it is one side, the process returns to S1 (see FIG. 11) and the subsequent flow is repeated.

The present invention is not limited to the illustrated embodiment, and it goes without saying that various improvements and design changes can be made without departing from the spirit of the present invention.

[0045]

As can be seen from the above description, according to the first aspect of the present invention, even for wafers of different production lots, the operator does not need to perform position correction, and the production efficiency can be improved. .

Further, according to the second aspect of the present invention, the number of times of position recognition on a wafer can be reduced, and re-bonding to a bump-bonded IC chip can be prevented.

Further, according to the third aspect of the present invention, the occurrence of a defect can be suppressed by automatically correcting the displacement of the camera unit, and the camera offset can be manually adjusted as in the prior art. There is no need to make adjustments, and work efficiency can be improved.

Further, according to the fourth invention of the present application,
It is possible to automatically correct the displacement of the camera unit and suppress occurrence of a defect.

[Brief description of the drawings]

FIG. 1 is a plan view showing an overall arrangement of a bump bonding apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of the bonding head according to the embodiment.

FIG. 3 is an explanatory view showing a step of a bonding operation by the bonding head.

FIG. 4 is a perspective view of a bonding stage according to the embodiment.

FIG. 5 is an explanatory diagram showing an automatic search process of a recognition mark attached to each IC on a wafer placed on the bonding stage.

FIG. 6 is a plan view showing one half of a wafer on which a plurality of IC chips are set.

FIG. 7 is an explanatory diagram showing a bump bonding route in block units.

FIG. 8 is an explanatory diagram showing a bump bonding route for each IC chip.

FIG. 9 is an enlarged plan view showing an IC chip provided with a bat mark.

FIG. 10 shows an example of a recognition window obtained by a recognition camera.

FIG. 11 is a first flowchart of a bump bonding step.

FIG. 12 is a second flowchart of a bump bonding step.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Wafer 1B ... Block 1a ... Orifice 1c ... IC chip 10 ... Bump bonding apparatus 20 ... Bonding stage 24 ... Recognition camera 30 ... Bat mark 40 ... Camera unit 41 ... Lens barrel M ... Recognition mark

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Nobuhisa Watanabe, 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Shinji Kanayama 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A bump bonding method in which a camera unit capable of recognizing a position of an IC chip to be bonded forms a bump on a wafer on a bonding stage by using a bonding head disposed above a bonding operation mechanism. The camera unit searches for a first recognition position at which the first mark can be recognized when the mark to be recognized cannot be recognized at the first recognition point above the wafer; (1) A bump bonding method comprising a step of automatically registering a position as data after searching for a recognized position, and performing mark recognition based on the registered position data. 2. A bump bonding method in which a camera unit capable of recognizing a position of an IC chip to be bonded forms a bump on a wafer on a bonding stage by using a bonding head disposed above a bonding operation mechanism. A bump bonding method for performing position recognition and bump bonding of an IC chip on a predetermined area on a wafer in a block unit composed of a plurality of IC chips. 3. A bump bonding method in which a camera unit capable of recognizing a position of an IC chip to be bonded forms a bump on a wafer on a bonding stage by using a bonding head disposed above a bonding operation mechanism. A bump bonding method characterized in that a butt mark teaching function is provided so that a bat mark position with respect to a recognition mark position is input by teaching in advance and determined. 4. A bump bonding method in which a camera unit capable of recognizing a position of an IC chip to be bonded forms a bump on a wafer on a bonding stage by using a bonding head disposed above a bonding operation mechanism. A bump bonding method comprising: recognizing a center of a previously bonded bump; and automatically correcting a difference from NC data with respect to a camera offset value.