WO2018147164A1

WO2018147164A1 - Wire bonding device

Info

Publication number: WO2018147164A1
Application number: PCT/JP2018/003450
Authority: WO
Inventors: 一昭長野
Original assignee: 株式会社新川
Priority date: 2017-02-09
Filing date: 2018-02-01
Publication date: 2018-08-16
Also published as: JP6637623B2; JPWO2018147164A1; TW201834092A; TWI692043B

Abstract

This wire bonding device has: a piezoelectric element (16); an ultrasonic horn (14); a capillary (15), which presses a wire (21) to an electrode by being attached to a leading end of the ultrasonic horn (14),and which applies ultrasonic vibration to the wire (21); an arithmetic unit (60) that calculates, on the basis of the resonance frequency fr of the ultrasonic horn (14), power Powerreq or a bond load Freq to be supplied to the piezoelectric element (16); and a control unit (50) that adjusts, on the basis of the power Powerreq or the bond load Freq calculated by the arithmetic unit, power Power or a bond load F to be supplied to the piezoelectric element (16).

Description

Wire bonding equipment

The present invention calculates the power supplied to the piezoelectric element based on the resonance frequency of the ultrasonic horn, the load by which the capillary presses the wire against the electrode, and the power supplied to the piezoelectric element based on the calculated result. The present invention relates to a wire bonding apparatus that adjusts a load applied to an electrode.

A wire bonding apparatus that connects a semiconductor die electrode and a substrate electrode with a wire such as gold, aluminum, or copper is often used. The wire bonding apparatus presses a wire against each electrode with a bonding tool such as a capillary and ultrasonically excites the wire to bond the wire to the surface of the electrode. Ultrasonic vibration of a wire is achieved by resonating an ultrasonic horn with an ultrasonic vibrator, transmitting the vibration to the wire with a bonding tool such as a capillary, and pressing the wire against the electrode with the bonding tool from the bonding tool to the wire. This is done by transmitting ultrasonic vibrations. In order to perform good bonding in the wire bonding apparatus, it is necessary to adjust control parameters such as the pressing load of the wire and the energy input to the ultrasonic transducer.

For this reason, it has been proposed to adjust control parameters such as the pressing load of the wire and the energy input to the ultrasonic transducer based on the diameter of the wire bonded crimp ball and the shear strength of the wire bond (for example, patents) Reference 1).

Also proposed is a method for correcting the bonding load and the output of ultrasonic vibration based on the size of the semiconductor die, the elastic modulus of the adhesive bonding the semiconductor die to the substrate, the thickness, the bonding position, and the bonding temperature. (For example, refer to Patent Document 2).

JP 2012-74699 A Japanese Patent Laid-Open No. 11-176866

By the way, research by the inventors has revealed that the control parameter of the wire bonding apparatus depends on the resonance frequency of the ultrasonic horn. However, in the conventional techniques described in Patent Documents 1 and 2, the resonance frequency of the ultrasonic horn is not taken into account in the adjustment and correction of the control parameter. For this reason, in the prior art described in Patent Literatures 1 and 2, when wire bonding is performed by attaching an ultrasonic horn having a different resonance frequency, the control parameters cannot be adjusted and corrected appropriately, and a good wire is obtained. In some cases, bonding was difficult.

Therefore, an object of the present invention is to provide a wire bonding apparatus capable of suitable wire bonding using ultrasonic horns having different resonance frequencies.

A wire bonding apparatus according to the present invention is a wire bonding apparatus for bonding a wire to an electrode, and includes a piezoelectric element, an ultrasonic horn that is vibrated by the piezoelectric element and ultrasonically vibrates at a specific resonance frequency, and an ultrasonic horn. A capillary that is attached to the tip and presses the wire against the electrode and applies ultrasonic vibration to the wire, and power supplied to the piezoelectric element based on the resonance frequency of the ultrasonic horn, or a load that the capillary presses the wire against the electrode And a control unit that adjusts the power calculated by the calculation unit, the power supplied to the piezoelectric element based on the load, or the load by which the capillary presses the wire against the electrode. And

In the wire bonding apparatus of the present invention, the calculation unit calculates the power supplied to the piezoelectric element based on the resonance frequency of the ultrasonic horn and the load by which the capillary presses the wire against the electrode, and the control unit calculates the control unit The electric power supplied to the piezoelectric element may be adjusted based on the generated electric power.

In the wire bonding apparatus of the present invention, the calculation unit may calculate Power _req , which is power supplied to the piezoelectric element, by the following equation (1).

Here, f _r is the resonant frequency of the ultrasonic horn, F _req is load capillary presses the electrode, A is determined geometry a, the material of the bonding pad b, bonding speed c, the junction temperature d coefficient , B are coefficients determined by the material of the wire.

In the wire bonding apparatus of the present invention, the calculation unit may calculate A by the following equation (2).

Here, f is a function of the shape dimension a, the bonding pad material b, the bonding speed c, and the junction temperature d.

In the wire bonding apparatus of the present invention, the calculation unit calculates the load by which the capillary presses the wire against the electrode based on the resonance frequency of the ultrasonic horn and the electric power supplied to the piezoelectric element, and the control unit calculates the calculation unit. The load by which the capillary presses the wire against the electrode may be adjusted based on the applied load.

In the wire bonding apparatus of the present invention, the calculation unit may calculate F _req , which is a load by which the capillary presses the wire against the electrode, according to the following equation (3).

Here, _{f r} is the resonant frequency of the ultrasonic horn, _{Power req} is power supplied to the piezoelectric element, A is determined geometry a, the material of the bonding pad b, bonding speed c, the junction temperature d coefficients, B is a coefficient determined by the material of the wire.

The present invention can provide a wire bonding apparatus capable of suitable wire bonding using ultrasonic horns having different resonance frequencies.

It is a systematic diagram which shows the structure of the wire bonding apparatus in embodiment of this invention. It is explanatory drawing which shows the formation process of the free air ball in the wire bonding process of the wire bonding apparatus in embodiment of this invention. It is explanatory drawing which shows the joining process in the wire bonding process of the wire bonding apparatus in embodiment of this invention. It is explanatory drawing which shows the looping process in the wire bonding process of the wire bonding apparatus in embodiment of this invention. It is explanatory drawing which shows the joining process in the wire bonding process of the wire bonding apparatus in embodiment of this invention. It is a flowchart which shows operation | movement of the wire bonding apparatus in embodiment of this invention.

<Configuration of wire bonding equipment>
Hereinafter, an embodiment of a wire bonding apparatus 100 will be described with reference to the drawings. As shown in FIG. 1, a wire bonding apparatus 100 according to the present embodiment includes a frame 10, an XY table 11 attached on the frame 10, a bonding head 12 attached on the XY table 11, and a bonding head. 12, a bonding arm 13 attached to 12, an ultrasonic horn 14 attached to the tip of the bonding arm 13, a piezoelectric element 16 for ultrasonically vibrating the ultrasonic horn 14, and a capillary attached to the tip of the ultrasonic horn 14. 15, a heat block 17 that heats and adsorbs the substrate 20 to which the semiconductor die 19 is attached, a control unit 50, and a calculation unit 60. In FIG. 1, the XY direction indicates the horizontal direction, and the Z direction indicates the vertical direction.

The bonding head 12 is moved in the XY direction by the XY table 11. A Z-direction motor 30 that drives the bonding arm 13 in the vertical direction (Z direction) is provided inside the bonding head 12. The Z-direction motor 30 includes a stator 31 fixed to the bonding head 12 and a mover 32 that rotates around a rotation shaft 35. The mover 32 is integrated with the rear part of the bonding arm 13, and when the mover 32 rotates, the tip of the bonding arm 13 moves in the vertical direction. The height of the rotation center 33 of the rotation shaft 35 of the mover 32 (indicated by the intersection of the alternate long and short dash line 37 and the alternate long and short dash line 36 in FIG. 1) is substantially the same as the bonding surface. Therefore, when the mover 32 rotates, the tip of the capillary 15 moves up and down in a substantially vertical direction with respect to the upper surface of the electrode 19a (shown in FIG. 2A) of the semiconductor die 19. A flange 14a of the ultrasonic horn 14 is fixed to the tip of the bonding arm 13 with a bolt 14b. Further, a recess 13 a for accommodating the piezoelectric element 16 is provided on the lower surface of the tip portion of the bonding arm 13.

The cross section of the ultrasonic horn 14 is narrowed from the flange 14a toward the tip in order to extend the ultrasonic vibration. A capillary 15 is attached to the tip of the ultrasonic horn 14. The capillary 15 has a cylindrical shape in which a hole for passing the wire 21 is provided at the center, and the outer diameter decreases toward the tip. The heat block 17 is attached on the frame 10. A heater 18 for heating the heat block 17 is attached to the heat block 17, and the substrate 20 is adsorbed and fixed on the upper surface thereof.

The driving power is supplied from the power source 41 to the stator 31 of the Z-direction motor 30 via the motor driver 42. In addition, driving power is supplied to the piezoelectric element 16 from the power source 43 via the piezoelectric element driver 44.

The calculation unit 60 is a computer having a CPU for performing calculation processing and a memory for storing programs and the like. As shown in FIG. 1, the calculation unit 60 includes a first calculation block 61 that calculates the power Power _req supplied to the piezoelectric element 16 necessary for bonding based on the resonance frequency fr of the ultrasonic horn 14, and the ultrasonic horn 14. A second calculation block 62 for calculating a load F _req for pressing the wire 21 against the

electrodes

19a and 20a of the semiconductor die 19 or the substrate 20 on the basis of the resonance frequency fr, and an input device (not shown). And an input unit 63 for receiving the data input.

The control unit 50 is a computer including a CPU 52 that performs arithmetic processing therein, a memory 53 that stores control programs, data, and the like, and a device / sensor interface 51 that performs input / output with devices and sensors. The CPU 52, the memory 53, and the device / sensor interface 51 are connected by a data bus 54.

The control unit 50 receives the power Power _req supplied to the piezoelectric element 16 calculated by the calculation unit 60 or the load F _req that the capillary 15 presses the wire 21 against the

electrodes

19 a and 20 a of the semiconductor die 19 or the substrate 20. The power Power supplied to the element 16 or the load F by which the capillary 15 presses the wire 21 against the electrode of the semiconductor die 19 or the substrate 20 is adjusted. Here, the control unit 50 adjusts the load F by which the capillary 15 presses the wire 21 against the electrode of the semiconductor die 19 or the substrate 20 by adjusting the power supplied to the Z-direction motor 30.

Hereinafter, the wire bonding process for connecting the electrode 19a of the semiconductor die 19 and the electrode 20a of the substrate 20 by the wire 21 by the wire bonding apparatus 100 shown in FIG. 1 will be briefly described with reference to FIGS. 2A to 2D. To do.

As shown in FIG. 2A, the tip of the wire 21 penetrating the capillary 15 is formed in a spherical free air ball 21a. In forming the free air ball 21a, a spark is generated between the torch electrode 22 and the tip of the wire 21 extending from the tip of the capillary 15, and the wire 21 is formed into a spherical shape by the heat. The substrate 20 on which the semiconductor die 19 is attached is fixed to the heat block 17 by suction and heated to a predetermined temperature by the heater 18.

Next, as shown in FIG. 2B, the Z-direction motor 30 is driven to rotate the bonding arm 13, and the tip of the capillary 15 is lowered toward the electrode 19 a of the semiconductor die 19. Then, the free air ball 21 a is pressed onto the electrode 19 a of the semiconductor die 19, and at the same time, alternating power is supplied to the piezoelectric element 16. Then, the alternating power is converted into a mechanical motion that expands and contracts in the thickness direction by the inverse piezoelectric effect of the piezoelectric element 16. When the frequency at that time and the natural frequency of the ultrasonic horn 14 are synchronized, the entire ultrasonic horn 14 resonates so as to expand and contract in the axial direction. The capillary 15 attached to the tip of the ultrasonic horn 14 resonates ultrasonically in the bending direction with reference to the fastening portion with the ultrasonic horn 14. The free air ball 21 a and the electrode 19 a of the semiconductor die 19 are joined by pressing the free air ball 21 a against the electrode 19 a by the capillary 15 and ultrasonic vibration.

As shown in FIG. 2C, when the free air ball 21a is joined onto the electrode 19a of the semiconductor die 19, the wire 21 is looped while the wire 21 is fed out, and the capillary 15 is moved onto the electrode 20a of the substrate 20. Then, as shown in FIG. 2D, the capillary 15 is lowered and the wire 21 is pressed and bonded to the electrode 20 a of the substrate 20.

<Introduction of calculation formulas for the phonon conduction effect, the power supplied to the piezoelectric element based on the resonance frequency of the ultrasonic horn, and the load by which the capillary presses the wire against the electrode>
Before describing the operation of the wire bonding apparatus 100 of the present embodiment, the phonon conduction effect will be described. A phonon is defined as a discrete quantum that behaves like a wave propagating through a crystal at the speed of sound. It is generated by irradiating the surface of a certain substance or the surface of a certain crystal with the vibration of the piezo element (piezoelectric element 16). Due to the interaction of phonon generation, heat conduction, thermal expansion, and diffusion transfer occur. Unlike thermal energy being absorbed in the entire bulk of a material, phonons concentrate only on sites with lattice imperfections such as dislocations and lattice defects, resulting in thermal and mechanical changes. In wire bonding, the generation of phonons is increased by increasing the vibration frequency of phonons, and in the dislocation movement at the bonding interface between the wire 21 and the

electrodes

19a and 20a, the temperature of the movement inhibition minimum due to impurities / defects between metals. Has the effect of promoting the rise. (For example, refer nonpatent literature 1).

According to the phonon conduction effect, in the wire bonding apparatus 100 to which ultrasonic vibration is applied, the single amplitude y _req (μm) of the ultrasonic vibration at the tip of the capillary 15 necessary for obtaining the required shear strength at the bonding interface is It is represented by the following formula (4).

Here, A is a coefficient determined by the shape dimension “a”, the bonding pad material “b”, the bonding speed “c”, and the junction temperature “d” (see, for example, Non-Patent Document 2). That is, A is expressed as the following equation (2) using the function f.

B is a coefficient determined by the material of the wire 21.
fr is the resonance frequency fr of the ultrasonic horn 14, that is, the frequency (Hz) of ultrasonic vibration in wire bonding.

It is assumed that the electric energy (the amount of power, the unit is mWs) supplied to the piezoelectric element 16 is E, and the necessary power amount (the unit is mWs) for obtaining the required shear strength at the bonding interface is E _req . Since the interface bonding is achieved by the mechanical action of the amplitude motion of the capillary 15, if the required vibration speed (unit: m / s) is v _req , the required electric energy E _req is expressed by the following equation (5). It is shown by the formula.

Here, T _req is the process time (ms) required for bonding, Power _req is the power (mW) supplied to the piezoelectric element 16, and F _req is the wire 21 or free air ball 21 a from the capillary 15 to the electrode of the semiconductor die 19. A load (N) to be pressed to 19a is shown (hereinafter referred to as a bond load _Freq ). Equation (5) is established when it is assumed that apparent power due to modulation and frictional heat from the capillary 15 are not expressed in the wire bonding process.

Here, the relationship between the required electric energy E _req (mWs) and the wire bonding process is examined. In equation (5), when the process time is brought close to 0 to the limit and T _req → 0, the energy is “0”, and _therefore the following equation (6) is established.

When Expression (6) is differentiated with respect to time T, the power Power _req (mW) supplied to the piezoelectric element 16 is expressed by the following Expression (7).

Here, the vibration velocity v _req (m / s) is expressed by the following equation (8).

Substituting Equation (4) and Equation (2) into Equation (8) yields Equation (9) below.

When Expression (9) and Expression (2) are substituted into Expression (7), the power Power _req (mW) supplied to the piezoelectric element 16 is expressed by the following Expression (1).

A bond load F _req (N), which is a load by which the capillary 15 presses the wire 21 against the electrode 19 a of the semiconductor die 19, is expressed by the following equation (3).

<Calculation example of the electric power supplied to the piezoelectric element based on the resonance frequency of the ultrasonic horn and the load by which the capillary presses the wire against the electrode>
In the following, a calculation example of the electric power Power supplied to the piezoelectric element 16 and the load F by which the capillary 15 presses the wire 21 against the electrode 19a based on the resonance frequency fr of the ultrasonic horn 14 using the previously introduced equation will be shown.

The coefficients A and B in each equation can take various values depending on the material, diameter, etc. of the wire 21. For example, a gold wire 21 with a diameter of 30 (μm) is used, and a free diameter of 55 (μm) is used. When the air ball 21a is bonded onto the electrode of the semiconductor die 19 deposited with 0.8 (μm) aluminum, the coefficient A is 1.85 and the coefficient B is 0.0016. In the following example, calculation examples in the case where the coefficient A and the coefficient B are 1.85 and 0.0016, respectively, are shown.

When the coefficient A and the coefficient B are 1.85 and 0.0016, the resonance frequency fr of the ultrasonic horn 14 is 120 (kHz), and the bond load F _req = 0.147 (N), the piezoelectric element 16 needs to be supplied. The effective power Power _req (mW) is calculated as 30 (mW) from the equation (1). Further, when the resonance frequency fr of the ultrasonic horn 14 is changed from 120 (kHz) to 150 (kHz) and the power Power _req supplied to the piezoelectric element 16 is maintained at 30 (mW), the necessary bond load F _req ( N) is calculated to be 0.19 (N) by Equation (3).

Thus, the power Power _req (mW) that is required to be supplied to the piezoelectric element 16 when the bond load F _req (N) is defined based on the resonance frequency fr (kHz) of the ultrasonic horn 14 according to the equation (1). ) Can be calculated. Further, the required bond load F _req (N) when the power Power _req (mW) to be supplied to the piezoelectric element 16 is defined based on the resonance frequency fr (kHz) of the ultrasonic horn 14 is calculated by Expression (3). can do. Therefore, even when the ultrasonic horn 14 having a different resonance frequency fr (kHz) is used, the power Power _req (mW) that is required to be supplied to the piezoelectric element 16 or the necessary bond load F _req (N) is suitably adjusted. It becomes possible to do.

<Operation of wire bonding equipment>
Hereinafter, the operation of the wire bonding apparatus 100 of the present embodiment will be described with reference to FIG.

As shown in step S101 of FIG. 3, the input unit 63 of the calculation unit 60 receives the resonance frequency fr (kHz) of the ultrasonic horn 14 and the power supplied to the piezoelectric element 16 from the external input device (not shown) Power _req (mW ), Bond load F _req (N), shape dimension a, bonding pad material b, bonding speed c, junction temperature d, and coefficient B. Here, various values can be considered as the shape dimension a. For example, the diameter of the wire 21 or the diameter of the free air ball 21a may be used.

As shown in step S102 of FIG. 3, the input unit 63 adjusts the power _req (mW) supplied to the piezoelectric element 16 based on the input data, or adjusts the bond load F _req (N). Judge whether to do. Input unit 63, data is input in the bond force _{F req} (N), when the power supply _{Power req} to the piezoelectric element 16 (m) is not input, supplied to the piezoelectric element 16 power _{Power req} It is determined that the (mW) adjustment is to be performed, and the process proceeds to step S103 in FIG. Conversely, power supply _{Power req} to the piezoelectric element 16 (m) is input, when the data of the bond force _{F req} (N) is not input, adjusts the bond force _{F req} (N) The process proceeds to step S105 in FIG.

The input unit 63 receives the resonance frequency fr (kHz), bond load F _req (N), shape dimension a, bonding pad material b, bonding speed c, input in step S103 of FIG. The junction temperature d and the coefficient B are output to the first calculation block 61. The first calculation block 61 uses the data input from the input unit 63 to calculate the coefficient A according to Equation (2), and calculates the power supply Power _req (mW) to the piezoelectric element according to Equation (1). Output to the controller 50.

As shown in step S <b> 104 of FIG. 3, the control unit 50 uses the supply power Power (mW) to the piezoelectric element 16 as the supply power Power _req (mW) to the piezoelectric element 16 input from the first calculation block 61. As described above, the electric power supplied to the piezoelectric element 16 is adjusted by adjusting the piezoelectric element driver 44.

Further, the input unit 63 receives the resonance frequency fr (kHz) of the ultrasonic horn 14, the power _req (mW) supplied to the piezoelectric element 16, the shape dimension a, and the bonding pad input in step S 105 of FIG. 3. The material b, the bonding speed c, the junction temperature d, and the coefficient B are output to the second calculation block 62. The second calculation block 62 uses the data input from the input unit 63 to calculate the coefficient A according to the equation (2), calculates the bond load F _req (N) according to the equation (3), and sends it to the control unit 50. Output.

As shown in Step S <b> 106 of FIG. 3, the control unit 50 adjusts the motor driver 42 so that the bond load F (N) becomes the bond load F _req (N) input from the second calculation block 62. The current supplied to the Z direction motor 30 is adjusted. The current may be adjusted, for example, by storing a map that defines the relationship between the current value and the bond load F in the memory 53 and adjusting the current value based on this map.

<Effect of the wire bonding apparatus of this embodiment>
As described above, the wire bonding apparatus 100 according to the present embodiment needs to be supplied to the piezoelectric element 16 when the bond load F _req (N) is defined based on the resonance frequency fr (kHz) of the ultrasonic horn 14. The power Power _req (mW) is adjusted. Further, based on the resonance frequency fr (kHz) of the ultrasonic horn 14, the required bond load F _req (N) when the power Power _req (mW) supplied to the piezoelectric element 16 is defined can be adjusted. Therefore, even when the ultrasonic horn 14 having a different resonance frequency fr (kHz) is used, the power Pow (mW) supplied to the piezoelectric element 16 or the bond load F (N) is adjusted, and wire bonding is suitably performed. It becomes possible.

<Modification>
In the embodiment described above, the first calculation block 61 and the second calculation block 62 have been described as calculating the coefficient A by the input equation (2). However, the present invention is not limited to this, and for example, the shape dimension a The coefficient A may be determined using a map or a table that defines the correlation between the bonding pad material b, the bonding speed c, the junction temperature d, and the coefficient A. Further, when the ultrasonic horn 14 having a different resonance frequency fr is exchanged during the wire bonding process, the value of the coefficient A does not change, so that the value of the coefficient A used in the previous calculation is used as it is. You may make it use.

In addition, the calculation unit 60 of the wire bonding apparatus 100 of the embodiment has been described as having two calculation blocks, the first calculation block 61 and the second calculation block 62, but the calculation program is changed in one calculation block. Thus, the same calculation may be performed.

In the embodiment, the data used for the calculation is described as being input from an external input device. However, the present invention is not limited to this. For example, each data is stored in a memory inside the calculation unit 60 and the ultrasonic wave is stored. A vibration sensor for detecting the resonance frequency fr of the horn 14 is provided, and the resonance frequency fr of the ultrasonic horn 14 detected by the vibration sensor is input as input data from the input unit 63 to the calculation unit 60, and the data stored in the memory is used. The power Power _req (mW) or the bond load F _req (N) that needs to be supplied to the piezoelectric element 16 is calculated, and the power Power or the bond load F calculated to be supplied to the piezoelectric element 16 by the control unit 50 is calculated. The calculated power Power _req (mW) or the bond load F _req (N) may be adjusted. In this case, even when the ultrasonic horn 14 is changed to one having a different resonance frequency fr, the power Power supplied to the piezoelectric element 16 or the bond load F can be automatically adjusted to a suitable value, which is automatically suitable. Wire bonding can be performed. Since the resonance frequency fr of the ultrasonic horn 14 is the same frequency as the command of the alternating power output from the control unit 50 to the piezoelectric element driver 44, the control signal of the piezoelectric element driver 44 of the control unit 50 is sent to the calculation unit 60. You may make it detect by inputting.

10 frame, 11 XY table, 12 bonding head, 13 bonding arm, 13a recess, 14 ultrasonic horn, 14a flange, 14b bolt, 15 capillary, 16 piezoelectric element, 17 heat block, 18 heater, 19 semiconductor die, 19a, 20a Electrode, 20 substrate, 21 wire, 21a free air ball, 22 torch electrode, 30 Z direction motor, 31 stator, 32 mover, 33 rotation center, 35 rotation axis, 41, 43 power supply, 42 motor driver, 44 piezoelectric element Driver, 50 control unit, 51 device / sensor interface, 52 CPU, 53 memory, 54 data bus, 60 calculation unit, 61 first calculation block, 62 second calculation block, 63 input unit.

Claims

A wire bonding apparatus for bonding a wire to an electrode,
A piezoelectric element;
An ultrasonic horn that is vibrated by the piezoelectric element and vibrates ultrasonically at a specific resonance frequency;
A capillary that is attached to the tip of the ultrasonic horn and presses the wire against the electrode and applies ultrasonic vibration to the wire;
An arithmetic unit that calculates the power supplied to the piezoelectric element based on the resonance frequency of the ultrasonic horn, or the load by which the capillary presses the wire against the electrode;
A control unit that adjusts the electric power calculated by the arithmetic unit or the electric power supplied to the piezoelectric element based on the load, or the load by which the capillary presses the wire against the electrode. .
The wire bonding apparatus according to claim 1,
The calculation unit calculates power supplied to the piezoelectric element based on a resonance frequency of the ultrasonic horn and a load by which the capillary presses the wire against the electrode,
The said control part is a wire bonding apparatus which adjusts the electric power supplied to the said piezoelectric element based on the said electric power which the said calculating part calculated.
The wire bonding apparatus according to claim 2,
The said calculating part is a wire bonding apparatus which calculates Power req which is the electric power supplied to the said piezoelectric element by following formula (1).

here,
fr is the resonance frequency of the ultrasonic horn.
F req is a load with which the capillary presses the electrode.
A is a coefficient determined by the shape dimension a, the bonding pad material b, the bonding speed c, and the junction temperature d.
B is a coefficient determined by the material of the wire.
The wire bonding apparatus according to claim 3,
The said calculating part is a wire bonding apparatus which calculates said A by the following formula | equation (2).

Here, f is a function of the shape dimension a, the bonding pad material b, the bonding speed c, and the junction temperature d.
The wire bonding apparatus according to claim 1,
The calculation unit calculates a load by which the capillary presses the wire against the electrode based on a resonance frequency of the ultrasonic horn and electric power supplied to the piezoelectric element,
The said control part is a wire bonding apparatus which adjusts the load which the said capillary presses the said wire against the said electrode based on the said load which the said calculating part calculated.
The wire bonding apparatus according to claim 5,
The said calculating part is a wire bonding apparatus which calculates Freq which is the load which the said capillary presses the said wire against the said electrode by following formula (3).

here,
fr is the resonance frequency of the ultrasonic horn.
Power req is power supplied to the piezoelectric element.
A is a coefficient determined by the shape dimension a, the bonding pad material b, the bonding speed c, and the junction temperature d.
B is a coefficient determined by the material of the wire.
The wire bonding apparatus according to claim 6,
The said calculating part is a wire bonding apparatus which calculates said A by the following formula | equation (2).

Here, f is a function of the shape dimension a, the bonding pad material b, the bonding speed c, and the junction temperature d.