JP2017216314A - Bonding device, bonding method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding device capable of detecting an abnormal crush of a free air ball more accurately than a conventional configuration in which the abnormal crush of the free air ball is detected by using a load sensor, an abnormal crush discrimination method and a program for discriminating the abnormal crush.SOLUTION: A wire bonding device 1 comprises: an ultrasonic horn 31 including a vibrator 32 to which a drive voltage having a predetermined frequency is applied, thereby generating ultrasonic vibrations; a capillary 33 which is held in a tip of the ultrasonic horn 31 and to which the ultrasonic vibrations are applied, such that a free air ball B is crushed and bonded to electrodes 101 and 201; and discrimination means 53 for discriminating a crush state of the free air ball B based on a value of the drive voltage and a value of a drive current relative to the drive voltage when the capillary 33 crushes the free air ball B.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bonding apparatus, a bonding method, and a program.

  In a manufacturing process of a semiconductor device, a wire bonding apparatus that connects a pad that is an electrode of a semiconductor chip and a lead that is an electrode of a lead frame with a wire that is a thin metal wire is often used. The wire bonding apparatus is attached to an ultrasonic horn, a bonding arm driven to swing up and down by a drive motor, an ultrasonic horn attached to the bonding arm, a capillary attached to the tip of the ultrasonic horn A vibrator is driven to rotate the bonding arm to move the capillary in contact with and away from the pad or lead. The free air ball formed at the tip of the capillary is pressed against the pad and the wire is pressed against the lead to be crimped. In many cases, an ultrasonic horn is resonated by a vibrator and ultrasonic vibration is applied to the tip of the capillary for bonding.

  When bonding is performed by a wire bonding apparatus, a free air ball formed at the tip of a wire inserted into a capillary collides with the pad at a certain speed, and then is pressed against the pad with a constant load to be pressed against the pad to become a pressure-bonded ball. However, the wire and capillary vibrate in the pressing direction even during the subsequent pressing period with a constant load due to the impact, and the pressing load fluctuates due to this vibration, resulting in variations in the shape and diameter of the pressed ball, bonding failure, etc. May occur.

  Therefore, the load sensor detects the load in the contact / separation direction continuously on the bonding target applied to the bonding tool by the load sensor, and determines the bonding quality based on the impact load with the detected maximum load value as the impact load. Thus, there has been proposed a method for detecting abnormal crushing of a free air ball due to variations in the shape of the pressure-bonded ball and the diameter of the pressure-bonded ball (see Reference 1).

JP 2010-27699 A

  However, in the method of Patent Document 1, abnormal crushing of the free air ball is detected based on the load amount detected by the load detected by the load sensor. However, the load amount applied to the bonding tool when the abnormal crushing occurs is larger than that in the normal state. If it does not change, there is a problem that abnormal collapse cannot be detected. Furthermore, since the load sensor detects the load based on the amount of strain caused by the load and is provided on the flange away from the bonding tool, there is a problem that the responsiveness to the load fluctuation is poor.

  In addition, in the method of Patent Document 1, abnormal crushing of the free air ball is detected based on the impact load when the free air ball contacts the electrode. Therefore, the abnormal crushing occurs after the free air ball contacts the electrode. In such a case, there is a problem that abnormal crushing cannot be detected.

  For this reason, the present invention provides a bonding apparatus, an abnormal collapse determination method, and an abnormal collapse determination that can detect an abnormal collapse of a free air ball with higher accuracy than a configuration that detects an abnormal collapse of a free air ball using a conventional load sensor. The purpose is to provide a program.

[1] A wire bonding apparatus for bonding a wire having a free air ball formed at the tip thereof to a chip or substrate electrode placed on a bonding stage by applying a driving voltage having a predetermined frequency. An ultrasonic horn having a vibrator that vibrates ultrasonically, a capillary that is held at the tip of the ultrasonic horn and applied with ultrasonic vibration, crushes the free air ball and joins the electrode, and the capillary A bonding apparatus comprising: a determination unit that determines a collapse state of a free air ball based on a value of a drive voltage and a value of a drive current with respect to the drive voltage when crushing.

[2] The bonding apparatus according to [1], further including a calculation unit that calculates a phase difference between the drive voltage and the drive current, and the determination unit determines a collapsed state of the free air ball based on the phase difference.

[3] A calculation unit that calculates a phase difference between the driving voltage and the driving current and a standard deviation of the phase difference is further provided, and the determination unit determines a collapsed state of the free air ball based on the standard deviation. 1].

[4] An ultrasonic horn having a vibrator that vibrates ultrasonically when a drive voltage having a predetermined frequency is applied, and ultrasonic vibration is applied to the tip of the wire held by the tip of the ultrasonic horn. And a capillary for crushing the formed free air ball to join the chip or substrate electrode placed on the bonding stage and joining the wire on which the free air ball is formed to the electrode. A wire bonding method in which a free air ball is crushed by a capillary and a wire is bonded to an electrode, and a driving voltage applied to the vibrator when the wire is bonded to the electrode and a driving current with respect to the driving voltage are measured. And a step of determining a collapse state of the free air ball based on the driving voltage and the driving current. Method.

[5] The method further includes a step of calculating a phase difference between the driving voltage and the driving current and a standard deviation of the phase difference, and the step of determining determines a collapsed state of the free air ball based on the standard deviation. [4] The bonding method described in 1.

[6] An ultrasonic horn having a vibrator that ultrasonically vibrates when a drive voltage having a predetermined frequency is applied thereto, and a ultrasonic vibration that is held by the tip of the ultrasonic horn and applied to the computer. A free air ball formed on the tip of the substrate and crushing the capillary on the chip or substrate electrode mounted on the bonding stage, and a drive motor for driving the ultrasonic horn in the height direction. A program that functions as a control unit for controlling a wire bonding apparatus that bonds a wire on which an air ball is formed to an electrode. The control unit drives a drive motor to crush the free air ball with a capillary, and the wire is electroded. The driving means for bonding to the vibrator and applied to the vibrator when bonding the wire to the chip The driving current for the dynamic voltage and the drive voltage is measured, on the basis of the drive voltage and the drive current, and a determination means for determining state collapse of free air ball program.

[7] A calculation unit that calculates a phase difference between the drive voltage and the drive current and a standard deviation of the phase difference is further provided, and the determination unit determines a collapse state of the free air ball based on the standard deviation. [6] The program described in.

  According to the present invention, the abnormal collapse of the free air ball can be detected with higher accuracy than the configuration of detecting the abnormal collapse of the free air ball using the conventional load sensor.

FIG. 1 is a configuration diagram and a block diagram showing a main part of a wire bonding apparatus according to an embodiment of the present invention. FIG. 2 is a top view showing the structure of the ultrasonic horn. FIG. 3 is a schematic view showing a state in which the substrate and the chip on the bonding stage are fixed by the wind clamper from the upper surface. FIG. 4 is a flowchart showing an example of the operation of the wire bonding apparatus. FIG. 5 is a graph showing drive voltage values, where (a) is a value when no abnormal crushing occurs (normal time), and (b) is a value when abnormal crushing occurs (abnormal time). Value. 6A and 6B are diagrams showing values of drive currents, where FIG. 6A is a value at normal time, and FIG. 6B is a value at abnormal time. FIG. 7 is a graph showing the phase difference between the drive voltage and the drive current, where (a) shows the phase difference when normal and (b) shows the phase difference when abnormal. FIGS. 8A and 8B are diagrams showing fluctuations in the frequency of the drive voltage, in which FIG. 8A is a normal value and FIG. 8B is an abnormal value. FIG. 9 is a diagram showing fluctuations in the impedance of the vibrator, where (a) is a value at normal time and (b) is a value at abnormal time. 10A and 10B are schematic views of the chip electrode after bonding as viewed from above. FIG. 10A shows a normal state and FIG. 10B shows an abnormal state. 11 is a cross-sectional view of the chip electrode shown in FIG. 10, (a) is a cross-sectional view taken along line AA showing a normal time, and (b) is a cross-sectional view taken along line BB showing a normal time. is there.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram and a block diagram showing a main part of the wire bonding apparatus. FIG. 2 is a top view showing the structure of the ultrasonic horn.

  The wire bonding apparatus 1 includes an XY table 21 movably provided in the XY direction, a drive motor 22 disposed on the XY table 21, a bonding arm 30 that moves in the Z-axis direction by driving of the drive motor 22, Free air is generated at the tip of the wire W by generating a spark between the ultrasonic horn 31 fixedly held on the bonding arm 30, the bonding stage 41 for adsorbing and fixing the chip 100 or the substrate 200 to be bonded, and the wire W. An electric torch 23 for forming the ball B and a wind clamper 42 which is provided on the bonding stage 41 and fixes the substrate 200 from above. The wire bonding apparatus 1 is an apparatus for bonding a wire W having a free air ball B formed at the tip thereof to a chip 100 or a substrate 200 placed on a bonding stage 41. The substrate 200 includes a lead frame, a printed circuit board, a silicon substrate, and the like.

  Furthermore, the wire bonding apparatus 1 is a computer or the like configured by a CPU or the like, and includes a control unit 50 that controls each unit of the apparatus according to a program, a hard disk, and a memory, and stores programs, various apparatus data, and the like. A storage unit 61, a measurement unit 62 that measures a drive voltage and a drive current applied to the vibrator 32, which will be described later, and a power source 63 that supplies power to each unit of the apparatus.

  The bonding arm 30 is rotatably attached to the rotation axis O of the drive motor 22 and moves in the Z direction (up and down direction) by the drive of the drive motor 22. The rotation axis O of the bonding arm 30 is on the same plane as the surface of the substrate 200 adsorbed on the bonding stage 41 or the surface of the chip 100 mounted on the substrate 200.

  As shown in FIG. 2, the ultrasonic horn 31 includes a vibrator 32 in which a plurality of piezoelectric elements are stacked, a through hole 35 that holds a capillary 33, and a flange that protrudes laterally from an intermediate portion of the ultrasonic horn 31. 34 is provided. The ultrasonic horn 31 is fixed to the flange mounting surface 301 at the tip of the bonding arm 30 by a bolt 34 by a flange 34. The vibrator 32 is provided in an intermediate portion of the ultrasonic horn 31 and is stored in a region surrounded by the side wall of the ultrasonic horn 31.

  The vibrator 32 ultrasonically vibrates when a drive voltage having a predetermined frequency is applied from the power supply 63, and applies ultrasonic vibrations to the capillary 33. The capillary 33 transmits the ultrasonic vibration applied from the vibrator 32 to the free air ball B, and also moves the free air ball B to the chip 100 according to the lowering operation of the bonding arm 30 and the ultrasonic horn 31 by the drive motor 22. Apply a load to The capillary 33 joins the free air ball B to the chip electrode by a load and ultrasonic waves. The drive voltage applied to the vibrator 32 is, for example, in the range of ± 30 V, and the frequency thereof is, for example, in the range of 50 kHz to 160 kHz.

  The control unit 50 acquires the voltage value of the drive voltage and the voltage value of the drive current from the drive unit 51 that controls the drive of the drive motor 22 and the XY table 21, and the measurement unit 62, and the drive voltage is obtained from the voltage value and the current value. And the calculation means 52 for calculating the phase difference between the driving current and the standard deviation of the phase difference, and the determination for determining whether or not the abnormal collapse of the free air ball B has occurred based on the standard deviation calculated by the calculation means 52 Means 53. Details of the determination unit 53 will be described later. Note that the drive unit 51, the calculation unit 52, and the determination unit 53 may execute each function by hardware.

  The ultrasonic horn 31 performs ultrasonic vibration in the Y direction along the longitudinal direction of the ultrasonic horn 31 by the vibrator 32 based on the frequency of the drive voltage. The ultrasonic vibration of the ultrasonic horn 31 is longitudinal vibration, and the longitudinal vibration refers to vibration in which the direction of vibration and the direction of amplitude are the same.

  FIG. 3 is a schematic view showing a state in which the substrate 200 and the chip 100 on the bonding stage 41 are fixed by the wind clamper 42 from above, and shows the chip 100 and the substrate 200 after the wires W are bonded. The wind clamper 42 is mounted with one or a plurality of chips 100 so that the upper surface of the chip 100 mounted on the substrate 200 is exposed by the opening 421 when the chip electrode 101 and the substrate electrode 201 are connected by the wire W. The substrate 200 is pressed against the bonding stage 41 and fixed. The wire bonding apparatus 1 connects the chip electrode 101 exposed through the opening 421 and the substrate electrode 201.

  One of the wires W is bonded to the chip electrode 101 by the first bonding portion W1 where the free air ball B is bonded, and the other is bonded to the chip electrode 101 without forming the free air ball B, and the second bonding is performed. It joins to the part W2, and connects between each electrode 101,201. Note that the chip electrode 101 and the substrate electrode 201 may be connected by the wire W by so-called reverse bonding in which the free air ball B is bonded to the substrate electrode 201.

(Operation of bonding equipment)
Next, the operation of the wire bonding apparatus 1 of the present invention will be described in detail. FIG. 4 is a flowchart showing an example of the operation of the wire bonding apparatus 1.

  When the substrate 200 on which the chip 100 is mounted by a substrate transport device (not shown) reaches the bonding area, the wire bonding apparatus 1 fixes the substrate 200 and the chip 100 to the bonding stage 41 by the wind clamper 42 and fixes the chip electrode 101 and the substrate electrode. Wire bonding for connecting 201 to the wire 201 is started.

  When the wire bonding is started, the wire bonding apparatus 1 feeds the wire W from a wire spool (not shown), generates a spark between the electric torch 23 and the wire W, and forms a free air ball B at the tip of the wire W ( Step S1).

  When the free air ball B is formed at the tip of the wire W, the drive means 51 of the control unit 50 drives the drive motor 22 to lower the ultrasonic horn 31 and the capillary 33 in the Z direction, so that the free air ball B is moved to the tip electrode. 101 is contacted (step S2).

  When the free air ball B is brought into contact with the chip electrode 101, the control unit 50 controls the power source 63 to apply a driving voltage having a predetermined frequency to the vibrator 32, and the ultrasonic horn 31 is ultrasonically vibrated by the driving voltage. Let At the same time, the driving means 51 further lowers the capillary 33 to apply a load to the chip electrode 101, and joins the free air ball B to the chip electrode 101 by the ultrasonic wave and the load (step S3).

  Further, the calculation means 52 of the control unit 50 acquires the voltage value of the drive voltage and the current value of the drive current from the measurement unit 62 within the period of joining the free air ball B, and stores the acquired voltage value and current value in the storage unit. 61 is stored. After the joining to the chip electrode 101 is completed, the calculation means 52 calculates the phase difference between the voltage value and the current value within the period during which the free air ball B is joined, and calculates the standard deviation of the phase difference (step S4). ).

  The determination means 53 of the control unit 50 determines whether or not the abnormal collapse of the free air ball B has occurred based on whether or not the calculated standard deviation exceeds a predetermined threshold (step S5). The threshold value is 2.5, for example, and if the standard deviation is equal to or greater than the threshold value, the determination unit 53 determines that the abnormal collapse of the free air ball B has occurred (S5: YES).

  If it is determined that the abnormal crushing of the free air ball B has occurred, the control unit 50 stops the bonding operation of the wire bonding apparatus 1 and notifies the user that the abnormal crushing has occurred via the apparatus screen, a buzzer, or the like (step S6). ). Note that the wire bonding apparatus 1 may be configured to store the chip 100 where the abnormal crush has occurred and the bonding location without stopping the bonding operation so that the location can be referred to.

  If it is determined that no abnormal collapse has occurred (S5: NO), the wire bonding apparatus 1 connects the wire W to the substrate electrode 201 and connects the chip electrode 101 and the substrate electrode 201 with the wire W. The control unit 50 determines whether or not the wires are connected to all the chips 100 mounted on the substrate 200 (step S7). If it is determined that the wiring is not completed, the control unit 50 determines whether the next electrode 101 or the next chip of the chip 100 is complete. Free air ball B is joined to 100 electrodes 101 (S7: NO). When determining that the wires W are connected to all the chips 100, the control unit 50 ends the bonding process for the substrate 200 (S7: YES).

(Detection of abnormal crushing)
Next, detection of abnormal crushing of the free air ball B will be described in detail. FIG. 5 is a graph showing the voltage value of the drive voltage, where (a) is a value when no abnormal crush occurs (normal time), and (b) is a case where an abnormal crush occurs (abnormal time). Is the value of 6A and 6B are diagrams showing the current value of the drive current, in which FIG. 6A is a normal value, and FIG. 6B is an abnormal value.

  Further, FIG. 7 is a graph showing the phase difference between the drive voltage and the drive current, where (a) is the phase difference at the normal time, and (b) is the phase difference at the abnormal time. FIGS. 8A and 8B are diagrams showing fluctuations in the frequency of the drive voltage, in which FIG. 8A is a normal value and FIG. 8B is an abnormal value. FIG. 9 is a diagram showing fluctuations in the impedance of the vibrator 32, where (a) is a normal value and (b) is an abnormal value.

  10A and 10B are schematic views of the chip electrode 101 after bonding when viewed from the top. FIG. 10A shows a normal state and FIG. 10B shows an abnormal state. 11 is a cross-sectional view of the chip electrode 101 shown in FIG. 10, (a) is a cross-sectional view taken along line AA showing a normal state, and (b) is a cross-sectional view taken along line BB showing an abnormal state. It is.

  As shown in FIGS. 5 and 6, the value of the drive voltage and the value of the drive current are substantially constant except for the rising time when the vibrator 32 is vibrated at the normal time. When abnormal crushing occurs, it fluctuates largely and irregularly even after rising.

  Further, as shown in FIG. 7, the phase difference between the drive voltage and the drive current is almost 0 degrees (deg) except for the rising time at the normal time, but exceeds 10 degrees after the rising at the abnormal time. Have fluctuated greatly. Further, as shown in FIG. 8, the frequency of the drive voltage also fluctuates greatly when abnormal, and as shown in FIG. 9, the impedance of the vibrator 32 also fluctuates greatly when abnormal. In FIG. 7, the standard deviation at normal time shown in (a) is 0.16, and the standard deviation at abnormal time shown in (b) is 5.55.

  Furthermore, as shown in FIGS. 10 and 11, when abnormal crushing occurs, the area of the crushing surface WA where the free air ball B is crushed by the chip electrode 101 is large and the crushing surface is larger than in the normal case. The periphery of the is non-uniform. Further, the height of the bonded ball is lower in the abnormal time than in the normal time.

  Examining from the graphs shown in FIGS. 5 to 9 and the schematic diagrams shown in FIGS. 10 and 11, when the free air ball B is joined to the chip electrode 101, the free air is more abnormal than the normal. It is presumed that the ball B vibrates in a wide range in the XY directions, and the vibration is irregular.

  In FIG. 5 to FIG. 9, it is estimated as follows that each value fluctuates at the time of abnormality. In other words, when the free air ball B vibrates irregularly, irregular vibration different from the ultrasonic vibration caused by the vibrator 32 is transmitted to the vibrator 32. Irregular vibration is transmitted to the piezoelectric element of the vibrator 32, and an electromotive force is generated by applying pressure to the piezoelectric element. Due to this electromotive force, the impedance of the vibrator 32 fluctuates as shown in FIG. 9, so that the voltage value and current value, as well as the phase difference and frequency between the driving voltage and driving current also fluctuate.

  It is estimated as follows that the free air ball B vibrates in a wide range in the XY direction compared with the normal time. That is, as shown in FIG. 3, the substrate 200 is fixed by the wind clamper 42 so that the chip electrode 101 and the substrate electrode 201 are exposed, but the fixing by the wind clamper 42 is not sufficient, and the chip 100 is tilted, The substrate 200 may float from the bonding stage 41. When the chip 100 and the substrate 200 are not sufficiently fixed by the wind clamper 42, the chip 100 or the substrate 200 vibrates together with the free air ball B due to vibration when the free air ball B is crushed to the chip electrode 101. Alternatively, the free air ball B vibrates while sliding on the surface of the chip electrode 101 without a sufficient load being applied to the chip electrode 101. At this time, since the reaction force from the chip electrode 101 becomes small, the free air ball B oscillates irregularly over a wider range than normal.

  Furthermore, abnormal crushing of the free air ball B can also occur when there is a defect in the chip 100 due to chip cracking, chipping, or the like, or a bonding defect between the chip 100 and the substrate 200. Also, abnormal crushing may occur when the chip 100 is cracked by a load at the time of joining.

  If the free air ball B is abnormally crushed, the wire W is not sufficiently bonded to the chip electrode 101, so that the possibility that the wire W will be peeled off from the chip electrode 101 in a later resin sealing step or the like increases. A semiconductor device using the chip 100 becomes defective. Furthermore, when abnormal crushing occurs, the crushing surface WA may protrude from the chip electrode 101 and come into contact with another chip electrode 101 or the like.

(Effect of embodiment)
According to the present embodiment, the following effects can be obtained.
(A) By detecting abnormal crushing of the free air ball B based on the driving voltage and driving current for driving the vibrator 32, the abnormality of the free air ball B even when the pressing load does not change between normal and abnormal Crushing can be detected. Also, detection data with better responsiveness can be obtained than the configuration in which abnormal crushing is detected by the load detected by the load sensor by detecting the abnormal crushing of the free air ball B based on the driving voltage and the driving current. Therefore, it is possible to detect abnormal crushing of the free air ball B with higher accuracy than a configuration in which abnormal crushing is detected by a conventional load sensor.

(B) By detecting abnormal crushing of the free air ball B based on the driving voltage and driving current for driving the vibrator 32, the free air ball is brought into contact with the chip electrode 101 and then ultrasonic vibration is applied. The crushing state at the time of joining free air balls can be evaluated. Therefore, it is possible to detect abnormal crushing due to the influence of ultrasonic vibration that could not be detected by the conventional method.

  (C) By detecting abnormal crushing of the free air ball B after joining based on the standard deviation of the phase difference between the driving voltage and the driving current, it is possible to evaluate the vibration state and the pressing state over the entire pressing period. Thereby, it is possible to suppress erroneous detection of abnormal crushing due to noise and the effect of rising.

  (D) By detecting the abnormal collapse of the free air ball B based on the drive voltage and drive current, it is possible to detect the abnormality of the free air ball B even in a simple configuration that does not use a load sensor only by changing the software. it can.

  (E) Since the abnormal collapse of the free air ball B can be detected in the bonding process, the wire bonding apparatus 1 can be stopped or the abnormal location can be stored when the abnormal collapse occurs. Thereby, since the chip | tip 100 in which abnormal crushing generate | occur | produced can be excluded or repaired, the yield of a semiconductor device can be improved.

(Modification)
Although the embodiment has been described with respect to the wire bonding apparatus 1, the present invention is not limited to the wire bonding apparatus 1 that connects the chip electrode 101 and the substrate electrode 201 with the wire W, and only the bumps are connected to the chip electrode 101 or the substrate electrode 201. The present invention can also be applied to a bump bonder device that is bonded to the substrate.

  In the embodiment, it has been described that the determination unit 53 detects abnormal crushing based on the standard deviation of the difference between the voltage value and the current value. However, the determination unit 53 is not limited to the difference between the voltage value and the current value. You may detect abnormal crushing by the numerical value of an electric current value, the fluctuation | variation of a frequency, etc. Furthermore, not only the standard deviation but also other methods may be used to evaluate the difference between the voltage value and the current value.

  In the embodiment, the determination unit 53 determines whether or not abnormal crushing has occurred. However, the determination unit 53 may determine a plurality of stages for the abnormal crushing and calculate an evaluation value for the abnormal crushing. It is good also as composition to do.

  Moreover, although the wire bonding apparatus 1 which does not have a load sensor was demonstrated in embodiment, of course, this invention is applicable to the wire bonding apparatus which has a load sensor.

  DESCRIPTION OF SYMBOLS 1 ... Wire bonding apparatus, 21 ... XY table, 22 ... Drive motor, 23 ... Electric torch, 30 ... Bonding arm, 31 ... Ultrasonic horn, 32 ... Vibrator, 33 ... Capillary, 34 ... Flange, 301 ..., Flange attachment Surface ... 302 ... Bolt 41 ... Bonding stage 42 ... Wind clamper 50 ... Control unit 51 ... Control unit 52 ... Calculation unit 53 ... Determination unit 61 ... Storage unit 62 ... Measurement unit 63 ... Power source DESCRIPTION OF SYMBOLS 100 ... Chip, 101 ... Chip electrode, 200 ... Substrate, 201 ... Substrate electrode, W ... Wire, W1 ... First joint, W2 ... Second joint, WA ... Fracture surface, B ... Free air ball, O …Axis of rotation

Claims (7)

A wire bonding apparatus for bonding a wire having a free air ball formed at a tip thereof to a chip or substrate electrode placed on a bonding stage,
An ultrasonic horn having a vibrator that vibrates ultrasonically when a drive voltage having a predetermined frequency is applied;
A capillary that is held at the tip of the ultrasonic horn and is applied with the ultrasonic vibration, crushing the free air ball and joining the electrode;
Determination means for determining a collapse state of the free air ball based on a value of the drive voltage or a drive current with respect to the drive voltage when the capillary crushes the free air ball,
Bonding equipment. A calculation means for calculating a phase difference between the drive voltage and the drive current;
The determination means determines a collapse state of the free air ball based on the phase difference.
The bonding apparatus according to claim 1. A calculation means for calculating a phase difference between the drive voltage and the drive current and a standard deviation of the phase difference;
The determination means determines a collapsed state of the free air ball based on the standard deviation.
The bonding apparatus according to claim 1. An ultrasonic horn having a vibrator that vibrates ultrasonically when a driving voltage having a predetermined frequency is applied, and the ultrasonic vibration is applied to the tip of the ultrasonic horn and formed at the tip of the wire. A wire bonding apparatus for joining the wire on which the free air ball is formed to the electrode, comprising a capillary for crushing the formed free air ball and joining the chip or substrate electrode mounted on the bonding stage. A wire bonding method used,
Crushing the free air ball by the capillary and bonding the wire to the electrode;
When the wire is bonded to the electrode, the driving voltage applied to the vibrator and the driving current with respect to the driving voltage are measured, and the collapse state of the free air ball is determined based on the driving voltage or the driving current. A step of determining,
Bonding method. A step of calculating a phase difference between the driving voltage and the driving current, and a standard deviation of the phase difference;
The step of determining determines a collapse state of the free air ball based on the standard deviation.
The bonding method according to claim 4. An ultrasonic horn having a vibrator that vibrates ultrasonically when a drive voltage having a predetermined frequency is applied to the computer, and the ultrasonic vibration is applied while being held at the tip of the ultrasonic horn, A capillary for crushing a free air ball formed at a tip to join a chip or substrate electrode placed on a bonding stage; and a drive motor for driving the ultrasonic horn in a height direction. A program for functioning as a control unit for controlling a wire bonding apparatus for bonding the wire on which an air ball is formed to the electrode,
The control unit drives the drive motor to crush the free air ball by the capillary, and a drive unit that joins the wire to the electrode;
When the wire is bonded to the chip, the driving voltage applied to the vibrator and the driving current with respect to the driving voltage are measured, and the collapse state of the free air ball is determined based on the driving voltage and the driving current. Determination means for determining,
program. A phase difference between the drive voltage and the drive current, and a calculation means for calculating a standard deviation of the phase difference;
The determination means determines a collapse state of the free air ball based on the standard deviation.
The program according to claim 6.

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