Ultrasonic bonding evaluation method

Abstract

The purpose of the present invention is to obtain an ultrasonic bonding evaluation method with which it is possible to accurately determine whether or not a bonding site is qualified. In step ST11, an ultrasonic vibration operation is performed on the plurality of bonding sites, and the bonding processing time of each of the plurality of bonding sites is measured together. In step ST12, the processing time of the ultrasonic vibration operation for each of the plurality of joining sites is identified as a plurality of joining processing times. In the step (ST13), on the basis of the result of comparison between the bonding processing time of each of the plurality of bonding parts and the reference processing time, the bonding qualification / disqualification result of each of the plurality of bonding parts is obtained. Specifically, in each of the plurality of bonding parts, a bonding part for which the bonding processing time is equal to or less than the reference processing time is determined to be "qualified", and a bonding part for which the bonding processing time is longer than the reference processing time is determined to be "disqualified".

Description

Technical Field

[0001] The present disclosure relates to an ultrasonic bonding evaluation method using an ultrasonic vibration bonding device during ultrasonic vibration operation. Background Art

[0002] Conventional ultrasonic vibration bonding devices pressurize a bonding member disposed on the surface of a substrate from above and apply ultrasonic vibrations from an ultrasonic vibration horn to bond the bonding member to the surface of the substrate. Examples of such ultrasonic vibration bonding devices include an ultrasonic bonding device disclosed in Patent Document 1 and an ultrasonic vibration bonding device disclosed in Patent Document 2.

[0003] Conventional ultrasonic vibration bonding devices perform ultrasonic vibration operations to apply ultrasonic vibrations to the bonded parts using ultrasonic vibration horns. To perform the ultrasonic vibration operations, an oscillation signal as an electrical signal is sent from an ultrasonic oscillator to a converter, which converts the electrical signal into ultrasonic vibrations, and provides the resulting ultrasonic vibrations to the ultrasonic vibration horn.

[0004] The ultrasonic oscillator outputs an oscillation signal oscillating at a set oscillation frequency to the converter. The oscillation signal is an electrical signal such as voltage or current.

[0005] When conventional ultrasonic vibration bonding devices bond multiple bonding locations at a certain interval on a bonding surface extending in a predetermined direction, a first unqualified location where bonding cannot be performed and a second unqualified location where bonding parts are broken may occur. The results of the cause investigation show that the friction resistance of the bonding parts is an important cause of the first and second unqualified locations.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2022-61631

[0009] Patent Document 2: International Publication No. 2018 / 025362 Summary of the invention

[0010] Problems to be solved by the invention

[0011] Conventional ultrasonic vibration bonding devices use an energy control method as an ultrasonic control method. That is, in conventional ultrasonic control methods, an action of continuously performing ultrasonic vibration action is used until the consumed energy calculated based on the oscillation signal from the ultrasonic oscillator reaches a preset energy (threshold energy). The above-mentioned consumed energy (W·s) is defined by the product of the electrical output value (W (watt)) and time (s (seconds)).

[0012] Fig.14 This is a graph showing the control content of the conventional ultrasonic control method. In this graph, the horizontal axis represents time (ms) and the vertical axis represents the electrical output value (power (W)). Fig.14 2 shows the change over time of the output information SC11 and SC12 in two joint scenarios (Case 11 and Case 12).

[0013] Here, the output information SC11 is an electrical output value (W) for causing the ultrasonic vibration horn to perform ultrasonic vibration operation in case 11, and the output information SC12 is an electrical output value (W) for causing the ultrasonic vibration horn to perform ultrasonic vibration operation in case 12.

[0014] Case 11 shows the change of output information SC11 over time when the friction resistance related to the joined parts is relatively small, and case 12 shows the change of output information SC12 over time when the above friction resistance is relatively large. "Friction resistance related to the joined parts" is the comprehensive friction resistance of the contact surface between the joined parts and the ultrasonic vibration horn (hereinafter, there are cases where it is only expressed as "contact surface") and the joining surface between the joined parts and the substrate (hereinafter, it is only expressed as "joining surface"). The above friction resistance is determined by the smaller friction resistance of the first friction resistance of the above contact surface and the second friction resistance of the above joining surface.

[0015] In case 11, since the frictional resistance is relatively small, the output information SC11 rises gradually. At time t12 when the output information SC11 reaches the output value W1, the consumed energy ΣE1 reaches the energy threshold EX, and the ultrasonic vibration operation ends.

[0016] In case 12, since the frictional resistance is relatively large, the output information SC2 rises steeply. At time t11 when the output value W9 is reached, the consumed energy ΣE2 reaches the energy threshold EX, and the ultrasonic vibration operation ends.

[0017] Thus, in the previous ultrasonic control method, if there is a deviation in the friction resistance related to the joined parts, a deviation will occur in the processing time of the ultrasonic vibration action (time t11, t12) or the final electrical output value (output value W1, W9) represented by the output information SC (SC1, SC2).

[0018] As a result, in conventional ultrasonic vibration bonding devices, when there is a deviation in the friction resistance between the multiple bonding locations and the bonded materials, there is a problem that the bonded materials cannot be bonded well by the ultrasonic vibration action of the ultrasonic vibration horn.

[0019] The ultrasonic vibration bonding device used in the ultrasonic bonding evaluation method disclosed in the present invention is designed to solve the above-mentioned problems. It is an improved ultrasonic vibration bonding device that can well bond the parts to be bonded through the ultrasonic vibration action performed by the ultrasonic vibration horn even if there is a deviation in the friction resistance related to the parts to be bonded.

[0020] An object of the present disclosure is to provide an ultrasonic welding evaluation method capable of accurately determining whether a joining portion is acceptable or not by ultrasonic welding during ultrasonic vibration operation using an improved ultrasonic vibration welding apparatus.

[0021] Means used to solve problems

[0022] The ultrasonic bonding evaluation method disclosed in the present invention is an ultrasonic bonding evaluation method using an ultrasonic vibration action of an ultrasonic vibration bonding device, comprising: step (a), using the ultrasonic vibration bonding device to perform the ultrasonic vibration action of applying ultrasonic vibration to a bonding part of a bonded member arranged on a substrate, wherein the ultrasonic vibration is generated based on an electrical signal including an electrical output value, and the ultrasonic vibration action is performed at the bonding part until the electrical output value reaches an output threshold value; step (b), identifying the processing time of the ultrasonic vibration action on the bonding part as a bonding processing time; and step (c), obtaining a bonding pass / fail result of the bonding part based on a comparison result of the bonding processing time with a reference processing time.

[0023] Effects of the Invention

[0024] The ultrasonic bonding evaluation method of the present disclosure obtains a bonding pass / fail result in step (c), and therefore can obtain a bonding pass / fail result with high accuracy for the bonding portion by setting an appropriate reference processing time. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an explanatory diagram schematically showing the structure of the ultrasonic vibration bonding device according to the first embodiment.

[0026] Figure 2 It indicates schematically Figure 1 An explanatory diagram of the ultrasonic oscillator and its surroundings shown.

[0027] Figure 3 This is a flowchart showing the processing procedure of the control operation of the ultrasonic vibration bonding device according to the first embodiment.

[0028] Figure 4 This is a graph showing the control contents of the ultrasonic control method of the ultrasonic vibration bonding device according to the first embodiment.

[0029] Figure 5 This is an explanatory diagram schematically showing an ultrasonic oscillator and its periphery according to the second embodiment.

[0030] Figure 6 This is a flowchart showing a control procedure of an ultrasonic control method of a conventional ultrasonic vibration bonding device.

[0031] Figure 7 It is an explanatory diagram showing an aluminum lead as a member to be joined and its surroundings.

[0032] Figure 8 This is a flowchart showing the processing steps of the ultrasonic bonding evaluation method according to the third embodiment.

[0033] Fig. 9 This is a flow chart showing a general manufacturing process of a solar cell.

[0034] Fig.10 This is an explanatory diagram showing the evaluation results of the ultrasonic bonding evaluation method according to the third embodiment in a tabular format.

[0035] Fig.11 This is a flowchart showing the processing steps of the ultrasonic bonding evaluation method according to the fourth embodiment.

[0036] Fig.12 Yes means Fig.11 Flowchart showing details of the process of setting the reference processing time shown.

[0037] Fig.13 This is an explanatory diagram showing in a tabular form the experimental results of the setting process of the reference processing time according to the fourth embodiment.

[0038] Fig.14 This is a graph showing the control contents of the conventional ultrasonic control method. DETAILED DESCRIPTION

[0039] <Principles of the Present Disclosure>

[0040] Conventional ultrasonic vibration bonding devices use energy control as an ultrasonic control method. Fig.14 As shown, when a plurality of joining locations are joined, a deviation occurs in the operation time (t12>>t11) of the ultrasonic vibration operation and the final electrical output value (W9>>W1).

[0041] The inventors of the present application focused on the electrical output value included in the oscillation signal rather than the energy calculated from the oscillation signal, etc., and assumed that there is an appropriate ideal output value WR in the joining of the joined members.

[0042] exist Fig.14When the friction resistance between the ultrasonic vibration horn and the workpiece is lower than usual as in case 11 shown, it can be imagined that even if the output value W1 is significantly lower than the ideal output value WR resulting in a relatively long ultrasonic vibration action, the workpieces cannot be well joined.

[0043] On the other hand, in Fig.14 As shown in case 12, when the friction resistance related to the joined parts is greater than usual, it is conceivable that the output value W9 greatly exceeds the ideal output value WR and causes a high possibility of damage to the joined parts. For example, when the joined parts are metal foils, it is conceivable that the metal foils are more likely to be damaged.

[0044] Thus, in the energy control method with the energy threshold EX as the termination condition, when the friction resistance is too large or too small compared to normal, good joining of the joined parts based on the ultrasonic vibration action cannot be performed. That is, when a plurality of joining parts have deviations in the friction resistance, the energy control method cannot be used to cope with it.

[0045] Therefore, the inventors of the present application have found that an output control method that pre-sets an output threshold WX that matches the ideal output value WR and continuously performs ultrasonic vibration until the electrical output value of the oscillation signal reaches the output threshold WX is an effective control method. The ultrasonic vibration bonding device that adopts the output control method as the ultrasonic control method is the following embodiments 1 and 2.

[0046] <Implementation Method 1>

[0047] Figure 1 It is an explanatory diagram schematically showing the structure of an ultrasonic vibration bonding device 101 as Embodiment 1 of the ultrasonic vibration bonding device of the present disclosure.

[0048] As shown in the figure, an ultrasonic vibration bonding device 101 includes an ultrasonic vibration horn 10 , a converter 11 , and an ultrasonic oscillator 12 as main components.

[0049] On the other hand, the substrate 14 is placed on the stage 20, and the material to be bonded 13 is placed on the surface of the substrate 14. As the material to be bonded 13, for example, a metal foil can be considered. The interface BF is the interface when the material to be bonded 13 and the substrate 14 are bonded. In this way, the material to be bonded 13 is placed on the stage 20 via the substrate 14.

[0050] The ultrasonic vibration horn 10 has a contact front end portion 10t at the front end, and performs an ultrasonic vibration operation of applying ultrasonic vibration to the workpiece 13 from the bottom surface of the contact front end portion 10t. Figure 1 The pressurizing cylinder 6 (see Figure 2 ) is a pressurizing action for pressurizing the ultrasonic vibration horn 10 toward the stage 20 side. Figure 1 In FIG. 1 , only the pressurizing force F6 during the pressurizing operation by the pressurizing cylinder 6 is shown.

[0051] The converter 11, which functions as an ultrasonic vibrator, applies ultrasonic vibration to the ultrasonic vibration horn 10. The ultrasonic oscillator 12 includes a control unit 1 as a main component, and the control unit 1 performs a control operation to control the ultrasonic vibration operation performed by the ultrasonic vibration horn 10.

[0052] Figure 2 1 is an explanatory diagram schematically showing an ultrasonic oscillator 12 and its surroundings. As shown in the figure, the control unit 1 in the ultrasonic oscillator 12 outputs an oscillation signal S12 including output information SC to the converter 11 as a control operation. The output information SC included in the oscillation signal S12 is an electrical output value for vibrating the ultrasonic vibration given to the ultrasonic vibration horn 10 from the converter 11 at a predetermined frequency. For example, when the oscillation signal S12 is a voltage signal, the amplitude (size) of the oscillation signal S12 can be considered as the output information SC.

[0053] The control unit 1 outputs the oscillation signal S12 as a control signal to the converter 11. The converter 11, which functions as an ultrasonic vibrator, applies ultrasonic vibration to the ultrasonic vibration horn 10 based on the oscillation signal S12.

[0054] As a result, the ultrasonic vibration horn 10 can perform an ultrasonic vibration operation of applying ultrasonic vibration to the joined material 13 from the bottom surface (joining surface) of the abutting tip portion 10 t .

[0055] The output information SC included in the oscillation signal S12 is an electrical output value required for the ultrasonic vibration to vibrate at a predetermined frequency in the ultrasonic vibration operation of the ultrasonic vibration horn 10. The amount of motion in the ultrasonic vibration given to the ultrasonic vibration horn 10 by the converter 11 is positively correlated with the output information SC, and the larger the output information SC, the larger the amount of motion in the ultrasonic vibration.

[0056] In this way, the control unit 1 outputs the oscillation signal S12 as a control signal to the converter 11 as a control operation, thereby controlling the ultrasonic vibration operation performed by the ultrasonic vibration horn 10 .

[0057] The control operation performed by the control unit 1 in the ultrasonic vibration bonding apparatus 101 of the first embodiment is characterized by including an operation continuation process of continuing the ultrasonic vibration operation until the output information SC (the electrical output value represented) becomes equal to or greater than the output threshold value WX.

[0058] The ultrasonic vibration horn 10 and the converter 11 have a friction resistance identification function for identifying the friction resistance associated with the joined member 13. In addition, the "friction resistance associated with the joined member 13" is the comprehensive friction resistance at the contact surface between the joined member 13 and the ultrasonic vibration horn 10 and the joining surface between the joined member 13 and the substrate 14, as described above. That is, the friction resistance is determined by the smaller friction resistance of the first friction resistance of the contact surface and the second friction resistance of the joining surface. The friction resistance identification function can be realized, for example, by utilizing existing technologies such as the piezoelectric principle. The detection component for the friction resistance identification function is, for example, arranged in the ultrasonic vibration horn 10, and the feedback signal SF containing the friction resistance information detected by the ultrasonic vibration horn 10 is output to the control unit 1 in the ultrasonic vibration horn 10 via the converter 11.

[0059] The feedback signal SF is output at a predetermined time interval. For example, 1 ms may be considered as the predetermined time.

[0060] In response to receiving the feedback signal SF, the control unit 1 obtains output information SC based on the frictional resistance information included in the feedback signal SF, and outputs the oscillation signal S12 including the newly obtained output information SC to the converter 11 as a control signal.

[0061] Then, the converter 11 applies ultrasonic vibration to the ultrasonic vibration horn 10 based on the oscillation signal S12 including the newly obtained output information SC.

[0062] During the execution of the ultrasonic vibration action, since the friction resistance information (the friction resistance value indicated) increases, the output information SC (the electrical output value indicated) also increases. This is because the friction resistance information and the output information SC are positively correlated. The control unit 1 in the ultrasonic oscillator 12 continuously outputs the oscillation signal S12 including the output information SC to the converter 11 until the output information SC becomes above the output threshold value WX, so the ultrasonic vibration action is continuously executed.

[0063] like Figure 2 As shown, the ultrasonic vibration bonding apparatus 101 of the first embodiment includes a pressurizing cylinder 6 as a pressurizing mechanism. The pressurizing cylinder 6 performs a pressurizing operation of pressurizing the ultrasonic vibration horn 10 toward the stage 20 with a pressurizing force F6 under the control of the control unit 1 .

[0064] The control unit 1 outputs a pressurizing control signal SP to the pressurizing cylinder 6 to thereby control the pressurizing operation of the pressurizing cylinder 6 .

[0065] Figure 31 is a flowchart showing the processing steps of the control operation of the ultrasonic vibration bonding device 101 according to the first embodiment. As described above, the control operation is performed by the control unit 1, and the ultrasonic vibration bonding device 101 adopts the output control method as the ultrasonic control method. Figure 3 The processing contents of the control operation of the control unit 1 will be described.

[0066] In step ST1, an output threshold WX is set as a termination condition parameter of the output control method. The output threshold WX is set to, for example, Fig.14 The ideal output value WR is shown.

[0067] Next, in step ST2, the pressurizing operation by the pressurizing cylinder 6 as the pressurizing mechanism is started. Specifically, the pressurizing operation by the pressurizing cylinder 6 is started by outputting a pressurizing control signal SP instructing the start of the pressurizing operation from the control unit 1 to the pressurizing cylinder 6.

[0068] Then, in step ST3, the contact between the abutting front end portion 10t of the ultrasonic vibration horn 10 and the workpiece 13 is recognized. For example, an existing detection function for detecting the presence or absence of contact between the abutting front end portion 10t and the workpiece 13 is provided in the pressurizing cylinder 6. When the detection function detects contact, the control unit 1 can recognize the contact state by outputting a contact detection signal S6 indicating the contact state to the control unit 1.

[0069] Next, in step ST4, the control unit 1 of the ultrasonic oscillator 12 starts the ultrasonic vibration operation of the ultrasonic vibration horn 10 by outputting an oscillation signal S12 including output information SC and oscillating at a predetermined frequency to the converter 11. The output information SC at the start of the operation is set to a relatively small value.

[0070] Thus, steps ST3 and ST4 are steps for starting the ultrasonic vibration operation using the contact between the abutting tip portion 10 t and the joined material 13 as a trigger.

[0071] Then, in step ST5, when the ultrasonic vibration operation starts, the converter 11 outputs the feedback signal SF to the control unit 1 of the ultrasonic oscillator 12. As described above, the feedback signal SF includes friction resistance information indicating the friction resistance value of the contact portion between the bottom surface of the contact tip 10t and the workpiece 13.

[0072] The control unit 1 newly calculates output information SC required to apply ultrasonic vibration of a predetermined frequency to the contact part based on the friction resistance information included in the feedback signal SF. The friction resistance information (represented friction resistance value) of the contact part and the output information SC (represented electrical output value) are positively correlated.

[0073] Next, in step ST6, the control unit 1 outputs the oscillation signal S12 including the output information SC to the transducer 11. Then, the transducer 11 imparts ultrasonic vibration based on the oscillation signal S12 including the output information SC to the ultrasonic vibration horn 10.

[0074] Since the frictional resistance at the contact portion increases during the execution of the ultrasonic vibration operation, the output information SC (the electrical output value represented) also increases. For example, when the output information SC represents a voltage value (V), the current value (A) that usually flows through the transducer 11 is constant, so the power value (W) of the transducer 11 also rises with the voltage value.

[0075] Next, in step ST7, the output information SC (the electrical output value represented) is compared with the output threshold WX. When the output information SC is a voltage value, the output threshold WX is a voltage value, and when the output information SC is a power value, the output threshold WX is a power value. As described above, since the current value flowing through the transducer 11 is constant, the voltage value and the power value are substantially equivalent electrical output values.

[0076] In step ST7, if {SC≥WX} is satisfied, then it proceeds to the next step ST8, and in the case where {SC≥WX} is not satisfied, it returns to step ST5.

[0077] In step ST7, in the case of {SC<WX}, steps ST5 to ST7 are repeatedly executed until {SC≥WX} is satisfied. Thus, step ST7 is a step of repeatedly executing steps ST5 and ST6 until the output information SC becomes equal to or higher than the output threshold WX.

[0078] Therefore, since the output of the effective oscillation signal S12 is continuously performed as a control signal until the output information SC reaches the output threshold WX, the ultrasonic vibration operation performed by the ultrasonic vibration horn 10 is continuously executed.

[0079] In step ST8, which is executed when {SC≥WX} is satisfied in step ST7, the pressurization operation performed by the pressurizing cylinder 6 as the pressurizing mechanism is terminated. Specifically, by outputting a pressurization control signal SP indicating the end of the pressurization operation from the control unit 1 to the pressurizing cylinder 6, the pressurization operation performed by the pressurizing cylinder 6 is terminated.

[0080] Then, in step ST9, the ultrasonic vibration operation performed by the ultrasonic vibration horn 10 is terminated. For example, by stopping the output of the oscillation signal S12 to the transducer 11, the ultrasonic vibration operation can be terminated.

[0081] Thus, steps ST8 and ST9 are executed after the output information SC becomes equal to or higher than the output threshold value WX, and are steps for terminating the pressurizing operation by the pressurizing cylinder 6 and the ultrasonic vibration operation by the ultrasonic vibration horn 10 .

[0082] Figure 4 1 is a graph showing the control contents of the ultrasonic control method of the ultrasonic vibration bonding device 101 according to Embodiment 1. In this graph, the horizontal axis represents time (ms) and the vertical axis represents the electrical output value (power (W)). Figure 4 The output information SC indicates a power value (W) as an electrical output value.

[0083] Case 1 shows the change over time of the output information SC1 when the friction resistance related to the joined member 13 is relatively small during the execution of the ultrasonic vibration action by the ultrasonic vibration horn 10. That is, case 1 shows, for example, the control content when the degree of slippage in the interface BF between the joined member 13 and the substrate 14 is relatively large, that is, when the second friction resistance in the interface BF as the joining surface is small.

[0084] On the other hand, case 2 shows the temporal change of the output information SC2 when the frictional resistance is relatively large. For example, case 2 shows the control content when there is almost no slip at the interface BF between the bonded material 13 and the substrate 14.

[0085] In case 1, since the frictional resistance is relatively small, the output information SC1 rises gradually and reaches the output threshold value WX at time t2, thus ending the ultrasonic vibration operation.

[0086] In case 2, since the frictional resistance is relatively large, the output information SC2 rises steeply and reaches the output threshold WX at time t1, thus ending the ultrasonic vibration operation. There is a relatively large time difference dt12 between time t1 and time t2.

[0087] In the case where there is almost no slippage at the interface BF (joining surface) between the joined member 13 and the substrate 14 and the frictional resistance associated with the joined member 13 is relatively large, as in the case where Figure 4 As shown in case 2, at time t1, the output information SC1 reaches the output threshold WX.

[0088] On the other hand, when the degree of slippage of the interface BF (joining surface) between the joined member 13 and the substrate 14 is relatively large and the frictional resistance associated with the joined member 13 is relatively small, as shown in FIG. Figure 4 As shown in case 1, at time t2 delayed by a time difference dt12 from time t1, the output information SC2 reaches the output threshold value WX.

[0089] In this way, the control unit 1 of the ultrasonic vibration bonding device 101 of embodiment 1 performs a control action including continuing the ultrasonic vibration action until the output information SC (SC1, SC2) reaches the output threshold value WX regardless of the level of the friction resistance related to the bonded member 13 at the above-mentioned contact portion.

[0090] (Conventional ultrasonic control method)

[0091] Figure 6 1 is a flow chart showing the control steps of the ultrasonic control method of the conventional ultrasonic vibration bonding device. As mentioned above, the energy control method has been used as the ultrasonic control method in the past. Here, referring to this figure, the processing steps of the conventional ultrasonic control method are described. Here, for the convenience of description, it is assumed that the conventional ultrasonic vibration bonding device has Figure 1 and Figure 2 The structure shown is the same as that of the structure shown, and the control operation is performed by the control unit which is the same as the control unit 1.

[0092] In step ST51, an energy threshold value EX is set as a termination condition parameter of the energy control method.

[0093] Next, in step ST52, Figure 3 Similarly in step ST2 shown, the pressurizing operation by the pressurizing cylinder 6 as the pressurizing means is started.

[0094] Then, in step ST53, Figure 3 Similarly, in step ST3 shown, the contact between the abutting tip portion 10 t of the ultrasonic vibration horn 10 and the joined material 13 is recognized.

[0095] Next, in step ST54, Figure 3 Similarly, in step ST4 shown, the ultrasonic vibration operation by the ultrasonic vibration horn 10 starts.

[0096] Then, in step ST55, Figure 3 Similarly, in step ST5 shown, output information SC required for applying ultrasonic vibration of a predetermined frequency to the contact portion generating the frictional resistance indicated by the frictional resistance information is newly calculated.

[0097] Next, in step ST56, Figure 3 Similarly, in step ST6 shown, the oscillation signal S12 including the output information SC is output to the converter 11.

[0098] Next, in step ST57, the energy consumption ΣE is calculated based on the output information SC of the oscillation signal S12. When the output information SC indicates a power value, the energy consumption ΣE is an integrated value of the change in the output information SC over time.

[0099] Next, in step ST58, the consumed energy ΣE is compared with the energy threshold EX.

[0100] In step ST58, if {ΣE≥EX} is satisfied, then after proceeding to the subsequent step ST59, in the case where {ΣE≥EX} is not satisfied, return to step ST55.

[0101] In step ST58, in the case of {ΣE<EX}, steps ST55 to ST58 are repeatedly executed hereafter until {ΣE≥EX} is satisfied.

[0102] Therefore, since the output of the effective oscillation signal S12 is continuously performed until the output information ΣE reaches the energy threshold EX, the ultrasonic vibration operation by the ultrasonic vibration horn 10 is continuously executed.

[0103] In step ST59, which is executed in the case where {ΣE≥EX} is satisfied in step ST58, similar to Figure 3 the step ST8 shown, the pressurization operation by the pressurization cylinder 6 is ended.

[0104] Then, in step ST60, similar to Figure 3 the step ST9 shown, the ultrasonic vibration operation by the ultrasonic vibration horn 10 is ended.

[0105] In this way, the conventional ultrasonic control method adopts an energy control method. Therefore, there will surely occur a situation such as Fig.14 in case 11 shown, where the ultrasonic vibration operation is ended at time t12 when the output information SC11 is significantly lower than the ideal output value WR (≈WX), or a situation such as Fig.14 in case 12 shown, where the ultrasonic vibration operation is ended only at t11 when the output information SC12 is significantly higher than the ideal output value WR.

[0106] (Effect)

[0107] The control operation executed by the control unit 1 in the ultrasonic oscillator 12 of the ultrasonic vibration bonding device 101 according to Embodiment 1 includes an operation continuation process of continuously performing the ultrasonic vibration operation until the output information SC becomes equal to or higher than the output threshold WX.

[0108] Therefore, during the execution of the ultrasonic vibration operation, the transducer 11 can surely apply ultrasonic vibration to the ultrasonic vibration horn 10 based on the oscillation signal S12 including the output information SC equal to or higher than the output threshold WX.

[0109] For example, in Figure 4 the case of case 2 shown, at time t1, the output information SC2 reaches the output threshold WX, and in Figure 4 In the case 1 shown in FIG. 1 , the output information SC1 reaches the output threshold value WX at the time t2 which is delayed by the time difference dt12 from the time t1. That is, the ultrasonic vibration bonding device of the first embodiment does not Fig.14 As in the case 11 shown in the figure, when the output information SC11 is significantly lower than the output value W1 of the ideal output value WR corresponding to the output threshold value WX, the ultrasonic vibration operation is terminated.

[0110] As a result, the ultrasonic vibration bonding device 101 according to the first embodiment can favorably bond the bonded material 13 to the surface of the substrate 14 through the ultrasonic vibration operation of the ultrasonic vibration horn 10 by appropriately setting the output threshold value WX.

[0111] Therefore, when joining a plurality of joining locations of the joined material 13, even if there is a deviation in the friction resistance with respect to the joined material 13 between the plurality of joining locations, the ultrasonic vibration joining device 101 of the first embodiment can join the plurality of joining locations satisfactorily.

[0112] For example, by using the ultrasonic vibration bonding device 101 to conduct an experiment of bonding a plurality of bonding locations with an experimental bonding member equivalent to the bonding member 13, it is possible to obtain an output threshold WX as an output value that enables good bonding regardless of the level of frictional resistance at the contact location with the bonding member 13. As the output threshold WX, for example, Fig.14 The ideal output value WR is shown.

[0113] In response to receiving the feedback signal SF, the control unit 1 of the ultrasonic vibration bonding device 101 of the first embodiment obtains output information SC based on the friction resistance information included in the feedback signal SF, and outputs the oscillation signal S12 including the newly obtained output information SC as a control signal.

[0114] Therefore, the control unit 1 of the ultrasonic vibration bonding device 101 according to the first embodiment can always output the oscillation signal S12 including the output information SC reflecting the friction resistance information included in the feedback signal SF to the converter 11 .

[0115] As a result, the ultrasonic vibration bonding apparatus 101 according to the first embodiment can apply ultrasonic vibrations that always vibrate at a predetermined frequency to the bonded material 13 from the ultrasonic vibration horn 10 by causing the ultrasonic vibration horn 10 to perform ultrasonic vibrations via the converter 11 .

[0116] The control unit 1 of the ultrasonic vibration bonding device 101 of the first embodiment executes the following steps: Figure 3In the control operation of steps ST1 to ST9 shown, when the output information SC reaches or exceeds the output threshold value WX, the pressurizing operation by the pressurizing cylinder 6 and the ultrasonic vibration operation by the ultrasonic vibration horn 10 can be quickly terminated.

[0117] The ultrasonic vibration bonding device 101 according to the first embodiment can cause the ultrasonic vibration horn 10 to perform ultrasonic vibration operation by outputting the oscillation signal S12 as a control signal from the control unit 1 included in the ultrasonic oscillator 12 to the converter.

[0118] <Implementation Method 2>

[0119] Figure 5 1 is an explanatory diagram schematically showing an ultrasonic oscillator 12B and its surroundings included in an ultrasonic vibration bonding device 102 according to Embodiment 2. Figure 1 The ultrasonic vibration bonding device 101 of the first embodiment shown is the same except that the ultrasonic oscillator 12 is replaced with an ultrasonic oscillator 12B.

[0120] Hereinafter, the same reference numerals are given to the same parts as those of the ultrasonic oscillator 12 of the first embodiment, and the description thereof will be appropriately omitted, and the description will be mainly focused on the characteristic parts of the ultrasonic oscillator 12B of the second embodiment.

[0121] like Figure 5 As shown, the control unit 1B in the ultrasonic oscillator 12B outputs the oscillation signal S12 indicating the output information SC to the converter 11, similarly to the control unit 1 of the first embodiment.

[0122] The ultrasonic oscillator 12B includes a timer 2 as a main component in addition to the control unit 1B. The control unit 1B receives time information S2 indicating the passage of time from the timer 2, recognizes the processing time of the ultrasonic vibration action, and outputs processing time information TP indicating the bonding processing time as the processing time of the ultrasonic vibration action to the outside.

[0123] The control unit 1B always receives time information S2 from the timer 2, for example, Figure 3 The elapsed time from the execution start time of the ultrasonic vibration operation in step ST4 to the execution end time of the ultrasonic vibration operation in step ST9 is recognized as the processing time of the ultrasonic vibration operation.

[0124] Next, the control unit 1B outputs processing time information TP indicating the bonding processing time as the processing time of the ultrasonic vibration operation to the outside of the ultrasonic vibration bonding apparatus 102 .

[0125] Since the control unit 1B in the ultrasonic oscillator 12B of the ultrasonic vibration bonding apparatus 102 of the second embodiment receives the time information S2 from the timer 2, it can relatively easily recognize the bonding processing time as the processing time of the ultrasonic vibration operation performed by the ultrasonic vibration horn 10 based on the time information S2.

[0126] Therefore, the ultrasonic vibration bonding apparatus 102 of the second embodiment outputs the processing time information TP indicating the bonding processing time to the outside, so that the user of the ultrasonic vibration bonding apparatus 102 can use the processing time information TP as a basis for judging whether the bonding is acceptable or not.

[0127] <Implementation Method 3>

[0128] By using the ultrasonic vibration bonding apparatus 101 of Embodiment 1 or the ultrasonic vibration bonding apparatus 102 of Embodiment 2 as an improved ultrasonic vibration bonding apparatus, it is possible to perform ultrasonic vibration operation for applying ultrasonic vibration to a bonding portion of the bonded material 13 disposed on the substrate 14 .

[0129] The ultrasonic bonding evaluation method according to the third embodiment of the ultrasonic bonding evaluation method of the present disclosure uses the ultrasonic vibration bonding device 102 according to the second embodiment as an improved ultrasonic vibration bonding device as an evaluation object.

[0130] Figure 7 1 is an explanatory diagram showing an aluminum lead wire 3 (3L, 3R) and its surroundings as a specific example of the bonded member 13. In this figure, an XYZ orthogonal coordinate system is drawn. Figure 7 The aluminum lead wire 3 as an electrode member used in a solar cell is shown as a member to be joined 13 (see Figure 1 ).

[0131] like Figure 7 As shown, an electrode forming region 4a is provided on the surface of the solar cell substrate 4. The substrate forming width KH4 along the Y direction of the solar cell substrate 4 is set to 700 mm, for example, and the substrate forming length KL4 along the X direction is set to 1600 mm, for example. The electrode forming region 4a is provided on the entire surface of the solar cell substrate 4.

[0132] The regions extending in the X direction at both ends of the electrode forming region 4a in the Y direction are the configuration regions of the aluminum leads 3. That is, in the electrode forming region 4a, the aluminum lead 3L is configured in the left end region on the +Y direction side, and the aluminum lead 3R is configured in the right end region on the Y direction side.

[0133] The solar cell substrate 4 is transported along the substrate transport direction D4, which is the +X direction. Therefore, in the electrode forming region 4a of the solar cell substrate 4, the aluminum lead 3L is arranged on the L side (left side) and the aluminum lead 3R is arranged on the R side (right side) based on the substrate transport direction D4.

[0134] Furthermore, for the aluminum lead 3L, the bonding parts L(1) to L(52) are set along the -X direction, and for the aluminum lead 3R, the bonding parts R(1) to R(52) are set along the -X direction. In this way, the bonding parts L(1) to L(52) and the bonding parts R(1) to R(52) are provided as a plurality of bonding parts.

[0135] Hereinafter, the aluminum leads 3L and 3R are collectively referred to as "aluminum leads 3", the joints L(1) to L(52) are collectively referred to as "joints L(i)", and the joints R(1) to R(52) are collectively referred to as "joints R(j)". In the joints L(i), "i" indicates any one of 1 to 52, and in the joints R(j), "j" indicates any one of 1 to 52.

[0136] In this way, as a plurality of bonding locations for the aluminum lead 3 , bonding locations L(i) for the aluminum lead 3L and bonding locations R(j) for the aluminum lead 3R are provided.

[0137] The joining at the joining position L(i) is performed, for example, by arranging the abutting front end portion 10t of the ultrasonic vibration horn 10 of the ultrasonic vibration joining device 102 above the aluminum lead 3L, while moving the solar cell substrate 4 along the substrate conveying direction D4 parallel to the X direction, and performing an ultrasonic vibration action of applying ultrasonic vibration to the joining position L(i) in the order of the joining positions L(1) to L(52).

[0138] Similarly, the joining at the joining position R(j) is performed, for example, by arranging the abutting front end portion 10t above the aluminum lead 3R, moving the solar cell substrate 4 along the substrate conveying direction D4, and performing an ultrasonic vibration action to apply ultrasonic vibration to the joining position R(j) in the order of the joining positions R(1) to R(52).

[0139] Figure 8 1 is a flowchart showing the processing steps of the ultrasonic bonding evaluation method according to Embodiment 3. Hereinafter, referring to this figure, the processing contents of the ultrasonic bonding evaluation method in ultrasonic vibration operation using the ultrasonic vibration bonding device 102 according to Embodiment 2 as an improved ultrasonic vibration bonding device will be described.

[0140] First, in step ST11 , ultrasonic vibration operation is performed on a plurality of joining locations, and the joining process time of each of the plurality of joining locations is measured together.

[0141] Specifically, the ultrasonic vibration bonding device 102 is used to perform ultrasonic vibration operation for applying ultrasonic vibration to the bonding parts L(1) to L(52) and the bonding parts R(1) to R(52) of the aluminum leads 3 (3L, 3R) arranged on the solar cell substrate 4. As a result, the aluminum lead 3L is bonded to the electrode forming region 4a at the bonding part L(i), and the aluminum lead 3R is bonded to the electrode forming region 4a at the bonding part R(j).

[0142] Thus, step ST11 is a step of using the ultrasonic vibration bonding device 102 to perform ultrasonic vibration on a plurality of bonding locations (L(i) and R(j)) of the aluminum lead 3 as a bonded member arranged on the solar cell substrate 4.

[0143] At this time, the ultrasonic vibration of the ultrasonic vibration horn 10 is generated based on the oscillation signal S12 output from the control unit 1B in the ultrasonic oscillator 12B. The oscillation signal S12 is an electrical signal, and includes output information SC as an electrical output value. The ultrasonic vibration operation is performed at the joints L(1) to L(52) and the joints R(1) to R(52) until the output information SC reaches the output threshold value WX.

[0144] Since the ultrasonic vibration bonding device 102 outputs the processing time information TP when executing the ultrasonic vibration operation, the bonding processing time of each of the bonding portion L(i) and the bonding portion R(j) can be easily measured by referring to the processing time information TP.

[0145] Then, in step ST12, the processing time of the ultrasonic vibration operation for each of the plurality of joint parts (joint parts L(1) to L(52) and joint parts R(1) to R(52)) is identified as a plurality of joint processing times. Since the processing time information TP is obtained for each joint part in ST11, the joint processing time when the ultrasonic vibration operation is performed for each of the plurality of joint parts can be easily identified.

[0146] Then, in step ST13, based on the comparison result of the joining process time of each of the plurality of joining locations (L(i) and R(j)) and the reference process time, the joining pass / fail result of each of the plurality of joining locations is obtained.

[0147] That is, among the plurality of joint locations, a joint location whose joint processing time is equal to or less than the reference processing time is judged as "acceptable", and a joint location whose joint processing time is longer than the reference processing time is judged as "unacceptable".

[0148] The reference processing time is set based on, for example, the takt time of a process for producing a solar cell. Fig. 9 1 is a flowchart showing a general process for manufacturing a solar cell. Fig. 9 A general process for manufacturing a solar cell will be described.

[0149] First, in step ST21, a manufacturing process of the solar cell substrate 4 is performed. After the execution of step ST21, the main part of the solar cell is formed on the solar cell substrate 4. The main part of the solar cell includes a back electrode, a light absorbing layer, a transparent conductive film (electrode forming region 4a), a buffer layer, and the like.

[0150] Then, in step ST22, a lead mounting process is performed to mount the aluminum lead 3 and the ribbon on the solar cell substrate 4. At this time, ultrasonic vibration operation is performed on a plurality of bonding locations (L(i) and R(j)) using the ultrasonic vibration bonding device 102.

[0151] Next, in step ST23, a lamination process (compression sealing process) is performed, and in step ST24, a final assembly process is performed. The final assembly process includes an assembly process of a frame and a JBOX (junction box).

[0152] Generally, a tact time is set for the solar cell manufacturing method having steps ST21 to ST24. In this case, a tact time is also set for the lead installation processing time of step ST22, and a reference processing time for each of the plurality of bonding locations (L(i) and R(j)) is set based on the tact time set for step ST22.

[0153] With respect to the thus set reference processing time, a joint portion whose joint processing time is longer than the reference processing time becomes an inappropriate joint processing time in terms of the relationship with the tact time set in step ST22. Therefore, in the ultrasonic joint evaluation method of embodiment 3, a joint portion whose joint processing time is longer than the reference processing time is judged as unqualified regardless of whether the joint itself is qualified or not.

[0154] Fig.10This is an explanatory diagram showing the evaluation results obtained by the ultrasonic bonding evaluation method of Embodiment 3 in a tabular form. In this figure, bonding locations of No. 1 to No. 5 are shown. The bonding location of No. 1 is bonding location R (10), the bonding location of No. 2 is bonding location R (20), the bonding location of No. 3 is bonding location L (10), the bonding location of No. 4 is bonding location L (20), and the bonding location of No. 5 is bonding location L (30). In addition, in the bonding locations of No. 1 to No. 5, the output values ​​of the output threshold WX shown in the output information SC as the final output are all 150 (W).

[0155] like Fig.10 As shown, the joining process time of No. 1 is 30 (ms), the joining process time of No. 2 is 32 (ms), the joining process time of No. 3 is 60 (ms), the joining process time of No. 4 is 45 (ms), and the joining process time of No. 5 is 100 (ms).

[0156] In this way, Fig.10 The results shown show that the bonding processing time of the bonding part L(i) tends to be longer than that of the bonding part R(j). The reason for this is that the formation height of the left end region of the electrode forming region 4a is different from that of other regions in the film forming process of step ST21.

[0157] exist Fig.10 In the evaluation results shown, the reference processing time is set to 50 (ms), and the bonding parts of No. 3 and No. 5 whose bonding processing time is 60 (ms) and 100 (ms) greater than 50 (ms) are judged as "unqualified", and the bonding parts of No. 1, No. 2 and No. 4 whose bonding processing time is less than 50 (ms) are judged as "qualified".

[0158] As described above, the ultrasonic bonding evaluation method of the third embodiment can judge as "failed" a bonding portion whose bonding process time is longer than the reference process time even though the bonding portion L(i) and the bonding portion R(j) can be bonded well.

[0159] The ultrasonic bonding evaluation method of the third embodiment obtains the bonding pass / fail result in step ST13 , and therefore can obtain a bonding pass / fail result with high accuracy for the bonding portion by setting an appropriate reference processing time.

[0160] In addition, the ultrasonic bonding evaluation method of embodiment 3 obtains multiple bonding pass / fail results corresponding to multiple bonding parts (bonding parts L(1) to L(52) and bonding parts R(1) to R(52)) in step ST13, so it is possible to determine unqualified parts of multiple bonding parts based on the multiple bonding pass / fail results.

[0161] exist Fig.10 In the example shown, among the joints L(1) to L(52) of the aluminum lead 3L, the joints L(10) and L(30) can be identified as failed portions judged as "failed".

[0162] In the ultrasonic bonding evaluation method of the third embodiment, the aluminum lead 3 as an electrode material used in a solar cell is used as the bonded material 13, and the reference processing time is set based on the tact time of step ST22 as a process of manufacturing a solar cell.

[0163] The ultrasonic joining evaluation method of the third embodiment sets the reference processing time based on the tact time of step ST22, and can judge as defective a joined portion joined at a joining processing time that may cause a problem in the tact time.

[0164] <Implementation Method 4>

[0165] The ultrasonic bonding evaluation method according to the fourth embodiment of the ultrasonic bonding evaluation method of the present disclosure evaluates the ultrasonic vibration operation of the ultrasonic bonding apparatus 102 according to the second embodiment as an improved ultrasonic bonding apparatus.

[0166] Fig.11 This is a flowchart showing the processing steps of the ultrasonic bonding evaluation method according to the fourth embodiment. Fig.12 Yes means Fig.11 The flowchart of the details of the process of setting the reference processing time in step ST11 is shown in FIG.

[0167] Step ST10 is performed before steps ST11 to ST13 and is a step for setting a reference processing time. Fig.12 The process of setting the reference processing time shown in step ST10 will be described.

[0168] First, in step ST101 , ultrasonic vibration operation is performed on a plurality of experimental joining locations, and experimental joining processing times of the respective plurality of experimental joining locations are measured together as a plurality of experimental joining processing times.

[0169] For the convenience of explanation, the following describes the use of Figure 7The solar cell substrate 4 shown in the figure is used as the experimental object. In this case, the experimental bonding members are the aluminum leads 3L and 3R, and the plurality of experimental bonding locations are the bonding locations L(1) to L(52) for the aluminum lead 3L and the bonding locations R(1) to R(52) for the aluminum lead 3R. Furthermore, the bonding processing time of each of the bonding locations L(1) to L(52) and the bonding locations R(1) to R(52) is the plurality of experimental bonding processing times.

[0170] Thus, step ST101 is a step of applying ultrasonic vibration to a plurality of experimental bonding locations (L(i) and R(j)) of the aluminum leads 3 (3L, 3R) as experimental bonding members arranged on the solar cell substrate 4 using the ultrasonic vibration bonding device 102. As a result, the aluminum lead 3L is bonded to the electrode forming region 4a at the experimental bonding location (L(i)), and the aluminum lead 3R is bonded to the electrode forming region 4a at the experimental bonding location (R(j)).

[0171] Since the ultrasonic vibration bonding device 102 outputs the processing time information TP when executing the ultrasonic vibration operation, the experimental bonding processing time of each of the plurality of experimental bonding locations (L(i) and R(j)) can be easily measured by referring to the processing time information TP.

[0172] Then, in step ST102, the experimental joining processing time for each of the plurality of experimental joining parts (L(i) and R(j)) is identified as a plurality of experimental joining processing times. Since the processing time information TP is obtained for each experimental joining part in ST101, the experimental joining processing time when the ultrasonic vibration action is performed for each of the plurality of experimental joining parts (L(i) and R(j)) can be easily identified as a plurality of experimental joining processing times.

[0173] Next, in step ST103, the bonding strength of each of the plurality of experimental bonding locations is measured as a plurality of experimental bonding strengths. The plurality of experimental bonding strengths can be measured by a conventional technique.

[0174] Then, in step ST104, based on the comparison results of each of the plurality of experimental joint strengths with the reference joint strength, the joint acceptance results of each of the plurality of experimental joint locations are obtained as a plurality of experimental joint acceptance results.

[0175] Fig.13This is an explanatory diagram showing the experimental results of the setting process of the reference processing time of step ST10 of embodiment 4 in a tabular form. In this figure, experimental joints No. 1 to 5 are shown. The joint position of No. 1 is the experimental joint R (10), the joint position of No. 2 is the experimental joint R (20), the joint position of No. 3 is the experimental joint L (10), the joint position of No. 4 is the experimental joint L (20), and the joint position of No. 5 is the experimental joint L (30). In addition, in the experimental joints No. 1 to No. 5, the output values ​​of the output threshold WX finally indicated by the output information SC are all 150 (W).

[0176] like Fig.13 As shown, the experimental joining processing time of No. 1 is 30 (ms), the experimental joining processing time of No. 2 is 32 (ms), the experimental joining processing time of No. 3 is 60 (ms), the experimental joining processing time of No. 4 is 45 (ms), and the experimental joining processing time of No. 5 is 100 (ms).

[0177] In Embodiment 4, the reference bonding strength is set to 2 (N). Fig.13 As shown, the experimental bonding strength of No. 1 is 4.84 (N), the experimental bonding strength of No. 2 is 5.11 (N), the experimental bonding strength of No. 3 is 1.52 (N), the experimental bonding strength of No. 4 is 2.12 (N), and the experimental bonding strength of No. 5 is 0.24 (N).

[0178] In this way, Fig.13 In the experimental results shown, the experimental bonding strength of the experimental bonding part L(i) tends to be weaker than that of the experimental bonding part R(j), and the experimental bonding treatment time of the bonding part L(i) tends to be longer than that of the bonding part R(j). Therefore, it is inferred that the experimental bonding strength and the experimental bonding treatment time are positively correlated.

[0179] exist Fig.13 In the experimental results shown, the reference joint strength is set to 2 (N), and the experimental joint parts No. 3 and No. 5, whose experimental joint strengths are 1.52 (N) and 0.24 (N) smaller than 2 (N), are judged as "unqualified", and the experimental joint parts No. 1, No. 2, and No. 4 are judged as "qualified". In this way, in step ST104, the pass / fail judgment results of No. 1 to No. 5 are obtained as a plurality of experimental joint pass / fail results.

[0180] Then, in step ST105, a reference processing time corresponding to the reference bonding strength is determined based on the plurality of experimental bonding pass / fail results and the plurality of experimental bonding processing times. Here, the experimental bonding processing times No. 1 to No. 5 are the plurality of experimental bonding processing times.

[0181] Considering that the experimental joint strength and the experimental joint processing time are positively correlated, the pass / fail determination results of No. 1 to No. 5 are compared with the experimental joint processing time of No. 1 to No. 5 to determine the reference processing time.

[0182] exist Fig.13 In the experimental results shown, a time range greater than 45 (ms) of the experimental joining processing time of No. 4 and smaller than 60 (ms) of the experimental joining processing time of No. 3 is a candidate for the reference processing time. For example, 50 (ms) can be determined as the reference processing time.

[0183] In this way, the ultrasonic bonding evaluation method of the fourth embodiment can set a reference processing time that can be estimated to indicate that the bonding portions are well bonded in step ST10 by conducting experiments of ultrasonic vibration operation on a plurality of test bonding portions.

[0184] Steps ST11 to ST13 executed after step ST10 are executed are executed with the same substrate as the solar cell substrate 4 as the experimental object as the manufacturing object. Fig.11 Steps ST11 to ST13 shown in FIG. Figure 8 Steps ST11 to ST13 in the ultrasonic bonding evaluation method of the third embodiment shown are substantially the same, and thus description thereof will be omitted.

[0185] The ultrasonic bonding evaluation method of the fourth embodiment obtains the bonding pass / fail result in step ST13. Therefore, similar to the third embodiment, by appropriately setting the reference processing time, a bonding pass / fail result with high accuracy can be obtained for the experimental bonding portion.

[0186] In addition, the ultrasonic bonding evaluation method of embodiment 4 sets a reference processing time corresponding to a reference bonding strength through ultrasonic vibration action on multiple experimental bonding parts through step ST10, and can infer that the bonding parts that exceed the reference processing time are lower than the reference bonding strength and judged as unqualified.

[0187] In addition, the ultrasonic bonding evaluation method of embodiment 4 is the same as embodiment 3. In step ST13, multiple bonding pass / fail results corresponding to multiple experimental bonding locations are obtained, so unqualified locations of multiple experimental bonding locations can be determined based on the multiple bonding pass / fail results.

[0188] In addition, in the ultrasonic bonding evaluation method of embodiment 4, when repeatedly performing pass / fail judgment on the aluminum lead 3 as the (experimental) bonded parts and the solar cell substrate 4 shared by the (experimental) bonding parts (L(i), R(j)), the reference processing time of step ST10 may be set once, and then the processing of step ST10 may be omitted and only the processing of steps ST11 to ST13 may be performed.

[0189] <Others>

[0190] In addition, the present disclosure can freely combine the various embodiments or appropriately modify or omit the various embodiments within the scope of the disclosure.

[0191] For example, in Embodiment 1 and Embodiment 2, the control unit 1 (1B) may be provided outside the ultrasonic oscillator 12 (12). Hereinafter, the control unit 1 provided outside is referred to as an "externally arranged control unit". It may also be configured so that the output form of the oscillation signal S12 of the ultrasonic oscillator 12 and the pressurizing operation of the pressurizing cylinder 6 are controlled by the externally arranged control unit. In this case, the externally arranged control unit outputs the oscillation signal S12 including the output information SC to the converter 11 via the ultrasonic oscillator 12.

[0192] Furthermore, in the ultrasonic bonding evaluation methods of Embodiments 3 and 4, an evaluation method in ultrasonic vibration operation using the ultrasonic vibration bonding device 102 of Embodiment 2 as an improved ultrasonic vibration bonding device is shown, but the ultrasonic vibration bonding device 101 may be used as an improved ultrasonic vibration bonding device instead of the ultrasonic vibration bonding device 102. However, in this case, it is necessary to use a method other than using the processing time information TP to measure and identify the bonding processing time of the bonding portion.

[0193] In the third and fourth embodiments, the processing of step ST10 is performed on the experimental joint portion of the experimental jointed materials. However, the joint portion of the jointed materials to be manufactured in the actual manufacturing process may be used as the experimental joint portion to determine the reference processing time.

[0194] For example, when the same manufacturing process accompanied by ultrasonic vibration action is performed on the joined parts in the order of the first and second manufacturing processes, a reference processing time can be set in step ST10 when the first manufacturing process is performed, and steps ST11 to ST13 can be performed in the second manufacturing process to determine whether the product is qualified or not, using the reference processing time calculated when the first manufacturing process is performed.

[0195] Description of symbols

[0196] 1.1B control unit

[0197] 2 Timer

[0198] 3. 3L, 3R aluminum lead wire

[0199] 4 Solar cell substrate

[0200] 4a Electrode formation area

[0201] 6 Pressurized cylinder

[0202] 10 Ultrasonic vibration horn

[0203] 11 Converter

[0204] 12, 12B ultrasonic oscillator

[0205] 13. Joined parts

[0206] 14 substrate

[0207] 20 units

[0208] 101, 102 Ultrasonic vibration bonding device

[0209] L(1) to L(52), R(1) to R(52) joints

Claims

1. An ultrasonic bonding evaluation method, which is an ultrasonic bonding evaluation method using an ultrasonic vibration bonding device in an ultrasonic vibration operation, characterized in that: have: Step (a), using the ultrasonic vibration bonding device to apply ultrasonic vibration to the bonding part of the bonded member arranged on the substrate, wherein the ultrasonic vibration is generated based on an electrical signal including an electrical output value, and the ultrasonic vibration action is performed at the bonding part until the electrical output value reaches an output threshold value; Step (b), identifying the processing time of the ultrasonic vibration action on the bonding part as the bonding processing time; as well as Step (c), based on the comparison result of the above-mentioned joining processing time and the reference processing time, obtaining the joining pass or fail result of the above-mentioned joining part.

2. The ultrasonic bonding evaluation method according to claim 1, wherein: The above-mentioned joint part includes a plurality of joint parts; The above-mentioned joining process time includes a plurality of joining process times corresponding to the above-mentioned plurality of joining locations; The step (a) includes a step (a-1) of performing the ultrasonic vibration action of applying the ultrasonic vibration to the plurality of joints, respectively, wherein the ultrasonic vibration action is performed on the plurality of joints until the electrical output value reaches the output threshold value; The step (b) includes a step (b-1) of identifying the plurality of bonding processing times; The step (c) includes a step (c-1) of obtaining a joining acceptance / failure result of each of the plurality of joining locations as a plurality of joining acceptance / failure results based on a comparison result of each of the plurality of joining processing times with the reference processing time.

3. The ultrasonic bonding evaluation method according to claim 2, wherein: The above-mentioned joined member is an electrode member used in a solar cell; The reference processing time is set based on the tact time of a process for producing the solar cell.

4. The ultrasonic bonding evaluation method according to claim 1 or 2, wherein: The method further comprises a step (d) of setting the reference processing time, which is executed before the steps (a) to (c); The above step (d) comprises: A step (d-1) of applying the ultrasonic vibration to a plurality of experimental bonding locations of experimental bonded members arranged on a substrate using the ultrasonic vibration bonding device; a step (d-2) of identifying the treatment time of the ultrasonic vibration action on the plurality of experimental bonding locations as a plurality of experimental bonding treatment times; A step (d-3) of measuring the bonding strength of each of the plurality of experimental bonding locations as a plurality of experimental bonding strengths; A step (d-4) of obtaining the joint pass / fail results of each of the plurality of experimental joint locations as a plurality of experimental joint pass / fail results based on the comparison results of each of the plurality of experimental joint strengths with the reference joint strength; and A step (d-5) of determining the reference processing time based on the plurality of experimental joining pass / fail results and the plurality of experimental joining processing times.

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