Ultrasonic coupling device

Abstract

This invention provides an ultrasonic bonding apparatus that reduces the probability of slippage between chips and workpieces, and between workpieces, thereby improving the quality of bonding. [Solution] The excitation operation of the ultrasonic composite element is controlled according to an amplitude instruction Qcmd that maintains the amplitude Q at an initial amplitude Qint = 0th designated amplitude Q0, while the translational operation of the ultrasonic bonding tip is controlled so that the translational speed V decreases while maintaining the translational speed V at the ith designated speed Vi (0≦i≦n) from the 0th designated speed V0 to the nth designated speed Vn (n=1). The excitation operation of the ultrasonic composite element is controlled according to an amplitude instruction Qcmd that maintains the amplitude Q at an initial amplitude Qint = 0th designated amplitude Q0, while the translational operation of the ultrasonic bonding tip is controlled so that the translational speed V increases while maintaining the translational speed V at the jth designated speed Vi (n≦i≦m) from the nth designated speed Vn to the mth designated speed Vm (m=2) as the final speed Pend.

Description

[Technical Field]

[0001] This invention relates to an ultrasonic bonding technology for joining multiple workpieces made of various materials such as metals using ultrasonic vibrations. [Background technology]

[0002] The present applicant has proposed a technique for joining multiple workpieces using ultrasonic composite vibration (see, for example, Patent Document 1). When the static pressure acting from the tip on the multiple workpieces is increased, the amplitude of the tip tends to decrease, and when the static pressure is decreased, the amplitude of the tip tends to increase. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent No. 7219495 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] However, if the static pressure is reduced to maintain the tip amplitude required for joining, slippage may occur between the tip and the workpiece and / or between the workpieces, potentially preventing proper joining of the multiple workpieces. On the other hand, if the static pressure is increased to prevent such slippage, the tip amplitude required for joining the multiple workpieces may not be maintained, potentially preventing proper joining of the multiple workpieces. When the tip is screwed to the horn, a suitable length is required to tighten the screw with the appropriate torque, and therefore the tip must be manufactured to be correspondingly longer. When high static pressure is applied to multiple workpieces from a long tip, the tip flexes, reducing the tip amplitude. When low static pressure is applied to multiple workpieces from a long tip, the tip flexes less, and the effect of the reduction in tip amplitude is smaller.

[0005] However, if the frictional force between workpieces decreases, there is a possibility that the workpieces may slide or displace from one another. Also, if a protrusion is formed on the tip of the chip and this protrusion does not bite into the workpiece sufficiently, there is a possibility that the chip and the workpiece may slide or displace from each other when the chip is vibrated.

[0006] Therefore, the present invention aims to provide an ultrasonic bonding apparatus that can improve the quality of bonding multiple workpieces by reducing the probability of slippage between chips and workpieces and between workpieces. [Means for solving the problem]

[0007] The ultrasonic bonding apparatus of the present invention is Ultrasonic vibration element, The system includes a control device that controls the excitation and translational movements of the ultrasonic vibration element, An ultrasonic bonding apparatus that bonds multiple workpieces by transmitting ultrasonic vibrations generated by the excitation operation of the ultrasonic vibration element to multiple workpieces via an ultrasonic bonding tip, The control device, With pressure P applied from the ultrasonic bonding tip to the multiple workpieces, an amplitude instruction Q is set to increase the amplitude Q of the ultrasonic bonding tip to a specified amplitude Q0. cmd Accordingly, the excitation operation of the ultrasonic vibration element is controlled, An amplitude instruction Q that maintains the amplitude Q at the specified amplitude Q0. cmd Accordingly, while controlling the excitation operation of the ultrasonic vibration element, the translational velocity V of the ultrasonic vibration element is set to an initial velocity V int After decreasing from the final velocity V for at least a specified period, end Speed ​​instruction V that leads to com Accordingly, the translational motion of the ultrasonic vibration element is controlled, An amplitude instruction Q that reduces the amplitude Q from the specified amplitude Q0 to 0. cmd When controlling the excitation operation of the ultrasonic vibration element accordingly, the translational velocity V is set to the final velocity V endReduce it from to 0. [Brief explanation of the drawing]

[0008] [Figure 1] Diagram illustrating the configuration of an ultrasonic bonding apparatus according to one embodiment of the present invention. [Figure 2] An explanatory diagram of an ultrasonic bonding method as a first embodiment. [Figure 3] An explanatory diagram of an ultrasonic bonding method as a second embodiment. [Modes for carrying out the invention]

[0009] (composition) The ultrasonic bonding apparatus 1 shown in Figure 1, as one embodiment of the present invention, comprises an ultrasonic composite vibration element 10, a horn tip 40 (ultrasonic bonding tip), an anvil 18, an operating device 20, a control device 22, a rotary drive device 220, a high-frequency power supply device 221, a translational drive device 222, and a state sensor 224. The anvil 18 may be omitted.

[0010] The ultrasonic composite vibration element 10 comprises a substantially cylindrical first ultrasonic vibration element 110, a substantially cylindrical, substantially cylindrical, or substantially bottomed cylindrical intermediate ultrasonic vibration element 100, and a substantially cylindrical or substantially bottomed cylindrical second ultrasonic vibration element 120.

[0011] The first ultrasonic vibration element 110 and the intermediate ultrasonic vibration element 100 are coaxially connected by a mechanical coupling mechanism (such as a bolt and / or clamp mechanism) in the middle or intermediate part of the ultrasonic composite vibration element 10. The intermediate ultrasonic vibration element 100 and the second ultrasonic vibration element 120 are coaxially connected by a mechanical coupling mechanism in the middle part of the ultrasonic composite vibration element 10. The first ultrasonic vibration element 110, the intermediate ultrasonic vibration element 100, and the second ultrasonic vibration element 120 may be integrally formed rather than mechanically connected.

[0012] The intermediate ultrasonic vibration element 100 may be a component of the first ultrasonic vibration element 110. That is, the first ultrasonic vibration element 110 may be composed of two ultrasonic vibration elements. In this case, the first ultrasonic vibration element 110 and the intermediate ultrasonic vibration element 100 may be integrally constructed rather than being mechanically connected. The intermediate ultrasonic vibration element 100 may be a component of the second ultrasonic vibration element 120. That is, the second ultrasonic vibration element 120 may be composed of two ultrasonic vibration elements. In this case, the second ultrasonic vibration element 120 and the intermediate ultrasonic vibration element 100 may be integrally constructed rather than being mechanically connected.

[0013] As shown in Figure 1, the first ultrasonic vibration element 110 is provided with a piezoelectric body 112 whose axial direction (a direction parallel to the first axis) is the direction of piezoelectric polarization.

[0014] As shown in Figure 1, the intermediate ultrasonic vibration element 100 has a substantially annular plate-shaped intermediate flange 102 that extends radially around its entire circumference at an intermediate position in its axial direction. The intermediate ultrasonic vibration element 100 is configured to be clamped or supported around its entire circumference by a clamping mechanism (not shown) at least at the intermediate flange 102. The intermediate flange 102 may be omitted if it is ensured that the intermediate ultrasonic vibration element 100 is supported by a mechanical support mechanism. As shown in Figure 1, the intermediate ultrasonic vibration element 100 is substantially cylindrical with an outer diameter that is substantially constant in the axial direction behind the intermediate flange 102 (to the left in Figure 1). As shown in Figure 1, the intermediate ultrasonic vibration element 100 is substantially cylindrical (a substantially frustoconical shape and a substantially cylindrical shape coaxially connected) with an outer diameter that is continuously reduced towards the tip partway through the intermediate flange 102 (to the right in Figure 1).

[0015] As shown in Figure 1, the second ultrasonic vibration element 120 is provided with a frequency adjustment element 122, which is a roughly regular octagonal plate shape with rounded corners, extending radially around its entire circumference at an intermediate position in its axial direction. The frequency adjustment element 122 adjusts the resonant frequencies of the longitudinal and torsional vibration components of the ultrasonic vibration. The external shape of the frequency adjustment element 122 may be a roughly circular, roughly elliptical, or roughly regular n-sided plate shape (e.g., n=4,6,8,12,16...) that shares a central axis with the second ultrasonic vibration element 120, or it may be a columnar or figurine shape, or any combination thereof.

[0016] As shown in Figure 1, the second ultrasonic vibration element 120 has a plurality of slits 124 formed on its outer surface behind the frequency adjustment element 122. The plurality of slits 124 may also be formed on the outer surface of the second ultrasonic vibration element 120 in front of the frequency adjustment element 122. The slits 124 extend diagonally when viewed from the side of the second ultrasonic vibration element 120, or extend axially while being displaced circumferentially in phase. The N (N=2, 3, ...) slits 124 may be arranged to have N rotational symmetry (e.g., N=8, 12, or 16) about the central axis of the second ultrasonic vibration element 120.

[0017] As shown in Figure 1, the second ultrasonic vibrating element 12 is provided with a roughly regular octagonal tip portion 126 with rounded corners that extends radially around its entire circumference at its axial tip position. The tip portion 126 has multiple holes 128 (or through holes) formed at each of the circumferentially spaced locations. The M (N=2, 3, ...) holes 128 may be arranged to have M rotational symmetry (e.g., M=4) around the central axis of the second ultrasonic vibrating element 12. Internal threads are provided on the inner surfaces of the holes 128.

[0018] The horn tip 40 has a base portion that is roughly frustoconical in shape and a tip portion that contacts the uppermost of the two workpieces W1, the first workpiece W1 and the second workpiece W2. The male thread provided at the base end of the horn tip 40 is screwed into the female thread provided in the hole 128 of the tip portion 126 of the second ultrasonic vibration element 12, thereby detachably fixing the horn tip 40 to the second ultrasonic vibration element 12. By preparing horn tips 40 of various shapes, the horn tip 40 can be appropriately replaced depending on the type of metal to be joined.

[0019] The male thread of the balancer, which adjusts the phase difference between longitudinal and torsional vibrations at the tip 126 of the second ultrasonic vibrating element 12 and, consequently, at the horn tip 40, may be screwed into the female thread of the hole 128, thereby allowing the balancer to be detachably fixed to the tip 126 of the second ultrasonic vibrating element 12.

[0020] The anvil 18 is positioned perpendicular to the tip of the horn tip 40. Multiple workpieces, such as a first workpiece W1 and a second workpiece W2, are placed on the upper surface of the anvil 18. These workpieces are, for example, metal plates and / or metal foils. The anvil 18 may be configured to be passively or actively displaced up and down in response to the pressure on the horn tip 40 received through the first workpiece W1 and the second workpiece W2.

[0021] The operating device 20 is comprised of, for example, a display that displays or outputs the displacement amount and / or pressure of the pressurizing block in response to the output signal of the state sensor 224. The display may be a touch panel display and may be configured to accept setting operations that allow the user to directly or indirectly specify parameters, such as one of several bonding modes that define the time-series pattern of the target pressure.

[0022] The control device 22 is composed of a microcomputer, and by extension, a processing unit (CPU, microprocessor, processor core, etc.) and a memory device (ROM, RAM, etc.). The control device 22 is configured to control the displacement operation of the pressure block by the translation drive device 222 based on the time series of pressure acting from the pressure block of the translation drive device 222 to the intermediate ultrasonic vibration element 100 (~pressure applied by the horn tip 40 to the first workpiece W1 and the second workpiece W2), which is represented by the output signal of the pressure sensor that constitutes the state sensor 224. The control device 22 is configured to control the displacement operation of the pressure block by the translation drive device 222 based on the amplitude Q of the ultrasonic composite vibration element 10. com The power supplied to the piezoelectric element 112 is configured to be controlled by feedback control so as to be controlled accordingly.

[0023] The high-frequency power supply unit 221 is configured to excite the first ultrasonic vibration element 110 in the axial direction by applying a high-frequency AC voltage to the piezoelectric body 112 of the first ultrasonic vibration element 110 in accordance with the power supplied from the commercial power supply (not shown).

[0024] The translational drive device 222 is equipped with a pressure block and is configured to apply pressure from the horn tip 40 to the first workpiece W1 and the second workpiece W2 by displacing a support mechanism such as a clamp mechanism that supports the intermediate ultrasonic vibration element 100 with the pressure block.

[0025] The state sensor 224 is composed of a pressure sensor that outputs a signal corresponding to the pressure acting on the intermediate ultrasonic vibration element 100 from the pressurizing block of the translational drive unit 222 (~pressure applied by the horn tip 40 to the first workpiece W1 and the second workpiece W2). The state sensor 224 includes an optical or non-contact amplitude sensor that outputs a signal corresponding to the amplitude Q of the horn tip 40 or its tip. Based on the output signal of the pressure sensor, the control device 22 controls the time series of the pressure to be constant or controlled in a specified manner.

[0026] (Ultrasonic bonding method (first embodiment)) The procedure of the ultrasonic bonding method as the first embodiment of the present invention by the ultrasonic bonding apparatus 1 will be described with reference to FIG. 2.

[0027] Before the time t = t0, in a state where the tip of the horn tip 40 is in contact with the first workpiece W1, the measured pressure P acting on the first workpiece W1 and the second workpiece W2 from the horn tip 40 mes is maintained at the initial pressure P int = P0 (the first specified pressure) (see the two-dot chain line in FIG. 2), and the vertical position H of the translational drive device 222, and thus the vertical position of the tip of the horn tip 40, is controlled to be constant (see the broken line in FIG. 2).

[0028] Immediately after the time t = t0, the amplitude Q of the tip of the horn tip 40 is increased from 0 to the initial amplitude Q int = Q0, and thereafter, the excitation operation of the ultrasonic composite vibration element 10 is started and continued according to the amplitude instruction Q int so as to be maintained at the initial amplitude Q (see the dotted line in FIG. 2). Further, the vertical position H of the translational drive device 222 is feedback-controlled so that the translational speed V (descending speed) of the translational drive device 222 becomes the initial speed V cmd = V0 (the first specified speed) (see the solid line in FIG. 2). As a result, the vertical position H of the translational drive device 222 gradually decreases from immediately after the time t = t0 (see the broken line in FIG. 2).

[0029] At this time, the measured pressure P mes gradually decreases from the initial pressure P int = P0 with the passage of time from the time t = t0 or immediately thereafter, and reaches the first specified pressure P1 at the time t = t0 (see the two-dot chain line in FIG. 2). Further, the measured amplitude Q mes ​​The power increases relatively rapidly from 0, then increases relatively gradually to reach the first specified amplitude Q1 at time t=t1 (see Figure 2 / dotted line). This is because the frictional force gradually increases from a state where the surfaces of the first workpiece W1 and the second workpiece W2 are rubbing against each other, and solid-state bonding of the base materials near the joint surfaces of the first workpiece W1 and the second workpiece W2 progresses. The power corresponding to this first specified amplitude Q1 is, for example, insufficient to complete the solid-state bonding of the first workpiece W1 and the second workpiece W2 (see Figure 2 / thick solid line).

[0030] Next, immediately after time t=t1, the translational speed V (downward speed) of the translational drive device 222 is equal to the initial speed V int The vertical position H of the translation drive unit 222 is feedback-controlled so that it decreases from V0 (0th designated speed) to the 1st designated speed V1 (see Figure 2 / solid line). As a result, the vertical position H of the translation drive unit 222 gradually decreases relatively slowly over time from time t=t1 or immediately thereafter (see Figure 2 / dashed line). During this time, the amplitude Q of the tip of the horn tip 40 decreases from the initial amplitude Q int An amplitude instruction Q that is continuously maintained cmd Accordingly (see Figure 2 / dotted line), the excitation operation of the ultrasonic composite vibration element 10 is controlled.

[0031] In this case, the measured pressure P increases with time, starting from time t=t1 or immediately after. mes The pressure decreases relatively rapidly from the first designated pressure P1, reaching a minimum value P 1+ After showing this, it rises relatively sharply, and then rises relatively gradually until it reaches the second specified pressure P2 at time t=t2 (see Figure 2 / dotted line). Furthermore, from time t=t1 or immediately thereafter, the measured amplitude Q increases with time. mes The amplitude rises relatively sharply from the first specified amplitude Q1, reaching a maximum value Q 1+After showing it, it decreases relatively rapidly, and then decreases relatively gently to reach the second specified amplitude Q2 (Q1 < Q2) at time t = t2 (see Fig. 2 / dashed-dotted line). This is because the frictional force gradually increases from the state where the surfaces of the first workpiece W1 and the second workpiece W2 are rubbing against each other, and the solid-phase bonding of the base material near the bonding surfaces of the first workpiece W1 and the second workpiece W2 progresses. The power corresponding to the first specified amplitude Q1 is, for example, sufficient power to complete the solid-phase bonding of the first workpiece W1 and the second workpiece W2 (see Fig. 2 / thick solid line).

[0032] Subsequently, immediately after time t = t2, the vertical position H of the translation drive device 222 is feedback-controlled so that the translation speed V (descending speed) of the translation drive device 222 increases from the first specified speed V1 to the second specified speed V2 (V1 < V2 ≤ V0) (see Fig. 2 / solid line). As a result, from time t = t2 or immediately after it, as time elapses, the vertical position H of the translation drive device 222 gradually decreases relatively rapidly (see Fig. 2 / dotted line). During this time, the amplitude Q of the tip of the horn tip 40 is maintained continuously at the amplitude instruction Q int such that it is maintained at the initial amplitude Q cmd According to this (see Fig. 2 / dot-dashed line), the excitation operation of the ultrasonic composite vibration element 10 is controlled.

[0033] At this time, the measured pressure P mes increases relatively rapidly from the second specified pressure P2 to the final pressure P end = P 2+ and then is maintained at the final pressure P end = P 2+ (see Fig. 2 / double-dotted line). Furthermore, as time elapses from time t = t2 or immediately after it, the measured amplitude Q mesAfter rapidly decreasing from the first specified amplitude Q1, it gradually decreases and reaches the third specified amplitude Q3 (Q3 < Q1) at time t = t3 (see the dashed-dotted line in FIG. 2). This is because the solid-phase bonding of the base materials near the joint surfaces of the first workpiece W1 and the second workpiece W2 progresses and the solid-phase bonding is completed. The power corresponding to the first specified amplitude Q1 is, for example, sufficient power to complete the solid-phase bonding of the first workpiece W1 and the second workpiece W2 (see the thick solid line in FIG. 2).

[0034] And immediately after time t = t3, the measured pressure P mes becomes the final pressure P end = P 2+ and decreases to 0 (see the dashed-dotted line in FIG. 2), and the vertical position H of the translational drive device 222 is feedback-controlled. As a result, the vertical position H of the translational drive device 222 slightly rises immediately after time t = t3 and is then maintained at that position (see the broken line in FIG. 2). Further, immediately after time t = t3, the amplitude Q of the tip of the horn tip 40 decreases from the initial amplitude Q int to 0 according to the amplitude instruction Q cmd (see the dotted line in FIG. 2), and the excitation operation of the ultrasonic composite vibration element 10 is stopped. At this time, the measured amplitude Q mes further decreases and reaches 0 immediately after t = t3 (see the broken line in FIG. 2).

[0035] In the first embodiment, while controlling the excitation operation of the ultrasonic composite vibration element 10 according to the amplitude instruction Q int = maintaining the amplitude Q at the initial amplitude Q cmd = the first specified amplitude Q0 (see the dotted line at times t = t0 to t2 in FIG. 2), the translational speed V is changed from the initial speed V int as the first specified speed V0 to the nth specified speed V n (n = 1), and the translational operation of the ultrasonic bonding tip 40 is controlled so that the translational speed V is maintained at the ith specified speed V i (0 ≦ i ≦ n) and then decreased (see the solid line at times t = t0 to t2 in FIG. 2). n may be 2 or more. The amplitude Q is maintained at the initial amplitude Q int = maintaining the amplitude Q at the initial amplitude Q cmdAccordingly, the excitation operation of the ultrasonic composite vibration element 10 is controlled (see the dotted line in Figure 2 / times t=t1~t3), and the translational velocity V is the nth specified velocity V n From final velocity P end The mth designated speed V m Until (m=2), the translational velocity V is set to the j-th designated velocity V i The translational movement of the ultrasonic bonding tip 40 is controlled to maintain (n≦i≦m) while increasing its position (see Figure 2 / solid line at times t=t1~t3).

[0036] Translational velocity V is the i-th designated velocity V i The i-th speed maintenance period T is maintained Vi The translational velocity V is the (i+1)th specified velocity V i+1 The i+1th velocity maintenance period T is maintained at this rate. Pi+1 The ratio (T Pi+1 / T Pi ) may be included in the range of 0.6 to 0.8.

[0037] initial speed V int Final velocity V end The ratio (V end / V int ) may be included in the range of 0.3 to 1.0.

[0038] (effect) The ultrasonic bonding apparatus with the above configuration improves the bonding quality of the first workpiece W1 and the second workpiece W2 by reducing the probability of slippage between the horn tip 40 and the first workpiece W1, and between the first workpiece W1 and the second workpiece W2 (between multiple workpieces).

[0039] (Ultrasonic bonding method (second embodiment)) The procedure for the ultrasonic bonding method as a second embodiment of the present invention using ultrasonic bonding apparatus 1 will be explained with reference to Figure 3.

[0040] Before time t=t0, with the tip of the horn tip 40 in contact with the first workpiece W1, the measured pressure P acts from the horn tip 40 on the first workpiece W1 and the second workpiece W2. mesInitial pressure P int The vertical position H of the translation drive unit 222, and consequently the vertical position of the tip of the horn tip 40, are controlled to be constant so that it is maintained at =P0 (the 0th designated pressure) (see Figure 3 / dotted line).

[0041] Immediately after time t=t0, the amplitude Q of the tip of the horn tip 40 changes from 0 to the initial amplitude Q. int It increases up to Q0, and thereafter the initial amplitude Q int Amplitude instruction Q that is maintained cmd Accordingly (see Figure 3 / dotted line), the excitation operation of the ultrasonic composite vibration element 10 is started and continued. Furthermore, the translational speed V (downward speed) of the translational drive device 222 is set to the initial speed V int The vertical position H of the translation drive unit 222 is feedback-controlled so that it becomes =V0 (0th specified speed) (see Figure 3 / solid line). As a result, the vertical position H of the translation drive unit 222 gradually decreases from immediately after time t=t0 (see Figure 3 / dashed line).

[0042] In this case, the measured pressure P increases over time, starting at time t=t0 or immediately after. mes Initial pressure P int The pressure gradually decreases from =P0 to the first specified pressure P1 at time t=t0 (see Figure 3 / dotted line). Furthermore, the measured amplitude Q decreases over time from time t=t0 or immediately after. mes The power increases relatively rapidly from 0, then increases relatively gradually to reach the first specified amplitude Q1 at time t=t1 (see Figure 3 / dotted line). This is because the frictional force gradually increases from the state in which the surfaces of the first workpiece W1 and the second workpiece W2 are rubbing against each other, and solid-state bonding of the base materials near the joint surfaces of the first workpiece W1 and the second workpiece W2 progresses. The power corresponding to this first specified amplitude Q1 is, for example, insufficient to complete the solid-state bonding of the first workpiece W1 and the second workpiece W2 (see Figure 3 / thick solid line).

[0043] Next, immediately after time t=t1, the translational speed V (downward speed) of the translational drive device 222 is equal to the initial speed V intThe vertical position H of the translational drive device 222 is feedback-controlled so as to decrease from V0 (the 0th specified speed) to the 1st specified speed V1 (see the solid line in FIG. 3). As a result, the vertical position H of the translational drive device 222 gradually decreases relatively gently over time from time t = t1 or immediately after that (see the broken line in FIG. 3). During this time, the excitation operation of the ultrasonic composite vibration element 10 is controlled according to the amplitude instruction Q int such that the amplitude Q at the tip of the horn tip 40 is continuously maintained at the initial amplitude Q cmd (see the dotted line in FIG. 3).

[0044] At this time, as time elapses from time t = t1 or immediately after that, the measured pressure P mes rapidly decreases from the 1st specified pressure P1, shows a minimum value P 1+ , then rapidly increases, and then increases relatively gently to reach the 2nd specified pressure P2 (P2 < P0) at time t = t2 (see the chain double-dashed line in FIG. 3). Further, as time elapses from time t = t1 or immediately after that, the measured amplitude Q mes rapidly increases from the 1st specified amplitude Q1, shows a maximum value Q 1+ , then rapidly decreases, and then decreases relatively gently to reach the 2nd specified amplitude Q2 (Q1 < Q2) at time t = t2 (see the single-dashed line in FIG. 3). This is because the frictional force gradually increases from the state where the surfaces of the 1st workpiece W1 and the 2nd workpiece W2 are rubbing against each other, and the solid-phase bonding of the base material near the bonding surface of each of the 1st workpiece W1 and the 2nd workpiece W2 progresses. The power corresponding to the 1st specified amplitude Q1 is, for example, sufficient power to complete the solid-phase bonding of the 1st workpiece W1 and the 2nd workpiece W2 (see the thick solid line in FIG. 3).

[0045] Subsequently, immediately after time t = t2, the vertical position H of the translational drive device 222 is feedback-controlled so that the translational speed V (descending speed) of the translational drive device 222 decreases from the first specified speed V1 to the second specified speed V2 (see the solid line in FIG. 3). As a result, over time from time t = t2 or immediately thereafter, the vertical position H of the translational drive device 222 further gradually and gently descends (see the dashed line in FIG. 3). During this period, the amplitude Q of the tip of the horn tip 40 is maintained continuously at the amplitude instruction Q int such that the excitation operation of the ultrasonic composite vibration element 10 is controlled according to the amplitude instruction Q cmd (see the dotted line in FIG. 3).

[0046] At this time, over time from time t = t2 or immediately thereafter, the measured pressure P mes rapidly decreases from the second specified pressure P2, shows a minimum value P 2+ (P 1+ < P 2+ ), then rapidly increases and then gradually increases to reach the second specified pressure P2 (P2 < P0) at time t = t2 (see the long dashed-dotted line in FIG. 3). Furthermore, over time from time t = t2 or immediately thereafter, the measured amplitude Q mes rapidly increases from the second specified amplitude Q2, shows a maximum value Q 2+ (Q 2+ < Q 1+ ), then rapidly decreases and then gradually decreases to reach the third specified amplitude Q3 (Q3 < Q1 < Q2) at time t = t3 (see the one-dot chain line in FIG. 3). This is because the solid-phase bonding of the base materials near the bonding surfaces of the first workpiece W1 and the second workpiece W2 progresses and the solid-phase bonding is completed. The power corresponding to the first specified amplitude Q1 is, for example, sufficient power to complete the solid-phase bonding of the first workpiece W1 and the second workpiece W2 (see the thick solid line in FIG. 3).

[0047] Then, immediately after time t = t3, the measured pressure P mes reaches the final pressure P end = P 2+The vertical position H of the translation drive device 222 is feedback-controlled so as to decrease from [value] to 0 (see FIG. 3 / dashed-dotted line). As a result, the vertical position H of the translation drive device 222 slightly increases immediately after time t = t3, and then is maintained at that position (see FIG. 3 / dotted line). Further, immediately after time t = t3, the amplitude instruction Q is such that the amplitude Q of the tip of the horn tip 40 decreases from the initial amplitude Q int to 0, cmd and in accordance with this (see FIG. 3 / dotted line), the excitation operation of the ultrasonic composite vibration element 10 is stopped. At this time, the actually measured amplitude Q mes further decreases to 0 immediately after t = t3 (see FIG. 3 / dotted line).

[0048] In the second embodiment, while controlling the excitation operation of the ultrasonic composite vibration element 10 in accordance with the amplitude instruction Q for maintaining the amplitude Q at the initial amplitude Q int = the 0th specified amplitude Q0 (see the dotted line in FIG. 3 at times t = t0 to t2), the translation operation of the ultrasonic bonding tip 40 is controlled so that the translation speed V decreases after being maintained at the ith specified speed V cmd from the 0th specified speed V0 as the initial speed V int to the nth specified speed V end as the end speed V n (n = 2) (see the solid line in FIG. 3 at times t = t0 to t3). n may be 3 or more.

[0049] For the ith speed maintenance period T i during which the translation speed V is maintained at the ith specified speed V Vi , the ratio (T i+1 / T Pi+1 ) of the (i + 1)th speed maintenance period T Pi+1 during which the translation speed V is maintained at the (i + 1)th specified speed V Pi may be included in the range of 0.6 to 0.8.

[0050] The ratio (V int / V end ) of the end speed V end to the initial speed V​​​​

[0051] (effect) The ultrasonic bonding apparatus with the above configuration improves the bonding quality of the first workpiece W1 and the second workpiece W2 by reducing the probability of slippage between the horn tip 40 and the first workpiece W1, and between the first workpiece W1 and the second workpiece W2 (between multiple workpieces).

[0052] (Other embodiments of the present invention) In the above embodiment, the ultrasonic bonding apparatus was of the ultrasonic composite vibration type, but in other embodiments, it may be an ultrasonic bonding apparatus of the ultrasonic simple harmonic vibration type. In such other embodiments, for example, the plurality of slits 124 may be omitted in the second ultrasonic vibration element 120, and the axial ultrasonic vibration (ultrasonic simple harmonic vibration) generated by the excitation of the first ultrasonic vibration element 110 in the axial direction may be transmitted to the horn tip 40. [Explanation of symbols]

[0053] 10. Ultrasonic combined vibration device 100...Intermediate ultrasonic vibration element 102...Intermediate flange 110...First ultrasonic vibration element 112. Piezoelectric material 120...Second ultrasonic vibration element 122...Frequency adjustment element 124... Slit 126‥Tip 128... Hole 18... Anvil 20‥Operation device 22. Control device 221‥High frequency power supply equipment 222... Translational drive device 224... State sensor 40. Horn tip (tip for ultrasonic bonding) W1...Work 1 W2... Second work.

Claims

1. Ultrasonic vibration element, The system includes a control device that controls the excitation and translational movements of the ultrasonic vibration element, An ultrasonic bonding apparatus that bonds multiple workpieces by transmitting ultrasonic vibrations generated by the excitation operation of the ultrasonic vibration element to multiple workpieces via an ultrasonic bonding tip, The control device, With pressure P applied from the ultrasonic bonding tip to the plurality of workpieces, the amplitude Q of the ultrasonic bonding tip is specified as amplitude Q 0 An amplitude instruction Q that raises the amplitude to a certain level. cmd Accordingly, the excitation operation of the ultrasonic vibration element is controlled, The amplitude Q is the specified amplitude Q 0 An amplitude instruction Q that maintains this value. cmd Accordingly, while controlling the excitation operation of the ultrasonic vibration element, the translational velocity V of the ultrasonic vibration element is set to an initial velocity V int After decreasing from the specified rate for at least a specified period, the final velocity V end Speed ​​instruction V that leads to com Accordingly, the translational motion of the ultrasonic vibration element is controlled, The amplitude Q is set to the specified amplitude Q 0 such that it decreases the amplitude Q from the specified value to 0 cmd When controlling the excitation operation of the ultrasonic vibration element according to the amplitude instruction Q, the translational speed V is decreased from the final speed V end to 0 Ultrasonic bonding equipment.

2. In the ultrasonic bonding apparatus according to claim 1, The control device, The amplitude Q is the specified amplitude Q 0 An amplitude instruction Q that maintains this value. cmd Accordingly, while controlling the excitation operation of the ultrasonic vibration element, the translational velocity V is set to the initial velocity V int Designated speed V as the 0th designated speed 0 From the nth designated speed V n (1 ≤ n) or the final velocity P end The nth designated speed V n Until the translation speed V is reached, the i-th designated speed V i The translational motion of the ultrasonic bonding tip is controlled to maintain (0 ≤ i ≤ n) and then decrease it. Ultrasonic bonding equipment.

3. In the ultrasonic bonding apparatus according to claim 2, The translational speed V is the i-specified speed V i The i-th velocity maintenance period T is maintained Vi The translational speed V is the i+1 specified speed V i+1 The i+1th velocity maintenance period T is maintained at this rate. Pi+1 The ratio (T Pi+1 / T Pi ) is included in the range of 0.6 to 0.8 Ultrasonic bonding equipment.

4. In the ultrasonic bonding apparatus according to claim 2, The initial velocity V int The final velocity V end The ratio (V end / V int ) is included in the range of 0.3 to 1.0 Ultrasonic bonding equipment.

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