Ultrasonic welding system, method of using same, and related workpiece including welded conductive pin

Abstract

An ultrasonic welding system is provided. The ultrasonic welding system includes a support structure for supporting a workpiece. The ultrasonic welding system also includes a welding head assembly comprising an ultrasonic transducer carrying an ultrasonic welding electrode. The ultrasonic welding system further includes a conductive pin supply configured to provide a plurality of conductive pins for welding using the ultrasonic welding electrode.

Description

[0001] This invention patent application is a divisional application of Chinese invention patent application CN202180039539.6 (international application number PCT / US2021 / 034847), filed on May 28, 2021, entitled "Ultrasonic welding system, method of use thereof and related workpiece including conductive pins for welding". Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 034,345, filed June 3, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to ultrasonic welding, and more particularly to improved systems and methods for performing ultrasonic welding operations, including conductive pin welding. Background Technology

[0004] Ultrasonic energy is widely used in forming interconnects between two or more materials. For example, wire bonders (e.g., ball bonders, wedge bonders, strip bonders, etc.) are used to bond wires or strips to the bonding location. However, wire bonding uses relatively low energy levels (e.g., welding force, ultrasonic energy, etc.). An exemplary wire bonder is sold by Kulicke and Soffa Industries, Inc., Fort Washington, Pennsylvania (United States).

[0005] Some applications involve joining materials different from wires. Welding has been considered for such applications. Ultrasonic welding is also a widely used technique. Ultrasonic welding uses an ultrasonic transducer (e.g., a sonotrode) to convert electrical energy into mechanical movement / scrubbing (e.g., linear movement / scrubbing, torsional movement / scrubbing, etc.). However, existing ultrasonic welding technologies and equipment are limited in providing solutions that meet market demands in terms of cost, operational efficiency, flexibility, portability, and related factors.

[0006] International Publication No. 2018 / 187364 (titled “Ultrasonic Welding Systems and Methods of Using the Same”), which was assigned to Kulicke and Soffa Industries, Inc., relates to improvements in ultrasonic welding technology, and the entire contents of said international publication are incorporated herein by reference.

[0007] Ultrasonic soldering, which includes ultrasonic pin bonding (where such pins are typically soldered and / or press-fitted into the power module), still requires improvement. Therefore, improvements to ultrasonic soldering techniques, including ultrasonic pin bonding, are desired. Summary of the Invention

[0008] According to another exemplary embodiment of the present invention, an ultrasonic welding system is provided. The ultrasonic welding system includes a support structure for supporting a workpiece. The ultrasonic welding system also includes a welding head assembly, the welding head assembly including an ultrasonic transducer carrying an ultrasonic welding electrode. The ultrasonic welding system further includes a conductive pin supply section configured to provide a plurality of conductive pins for welding using the ultrasonic welding electrode.

[0009] According to another exemplary embodiment of the present invention, a method for operating an ultrasonic welding system is provided. The method includes the steps of: (a) supporting a workpiece on a support structure of the ultrasonic welding system; and (b) welding conductive pins from a conductive pin supply portion of the ultrasonic welding system to the workpiece using an ultrasonic welding electrode of a welding head assembly of the ultrasonic welding system, the conductive pin supply portion including a plurality of conductive pins.

[0010] According to another exemplary embodiment of the present invention, a workpiece is provided. The workpiece includes: a substrate; and conductive pins ultrasonically welded to the substrate. Attached Figure Description

[0011] The invention is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, by convention, the various features in the drawings are not drawn to scale. Instead, for clarity, the dimensions of the various features have been arbitrarily enlarged or reduced. The drawings include the following figures: Figure 1 This is a block diagram side view of an ultrasonic welding system according to an exemplary embodiment of the present invention; Figure 2A This is a block diagram side view of another ultrasonic welding system according to another exemplary embodiment of the present invention; Figure 2B yes Figure 2B A three-dimensional view of the end portion of the ultrasonic welding electrode in an ultrasonic welding system. Figure 2C It comes from Figure 2B A side view of the conductive pins of the conductive pin supply section of the ultrasonic welding system; Figure 3A This is a block diagram side view of another ultrasonic welding system according to yet another exemplary embodiment of the present invention; Figure 3B-3C This is a side view diagram illustrating the use of Figure 3AThe ultrasonic welding system removes the conductive pins from the conductive pin supply section; Figure 3D It comes from Figure 3A A side view of the conductive pins of the conductive pin supply section of the ultrasonic welding system; Figure 4 This is a block diagram side view of another ultrasonic welding system according to yet another exemplary embodiment of the present invention; Figure 5 This is a block diagram side view of another ultrasonic welding system according to yet another exemplary embodiment of the present invention; Figure 6A-6G These are different views of the conductive pins and ultrasonic soldering electrodes, illustrating the alignment of the keying feature with different exemplary embodiments according to the present invention; and Figure 7 This is a block diagram side view of an ultrasonic welding system according to an exemplary embodiment of the present invention. Detailed Implementation

[0012] Figure 1 The figure illustrates an ultrasonic welding system 100. The ultrasonic welding system 100 includes an input workpiece supply unit 102 for providing workpieces 102a1, wherein the input workpiece supply unit 102 is configured to carry multiple workpieces 102a1 (e.g., the workpiece supply unit 102 may be a carrier such as a magazine handler for carrying multiple workpieces 102a1, or other supply structures suitable for application-specific workpieces, etc.). Exemplary workpieces 102a1 carried by the input workpiece supply unit 102 include power modules, components of power modules, lead frames, battery modules, etc. Workpieces 102a1 are provided from the input workpiece supply unit 102 (via any desired transport assembly, which may be included in a material handling system 104, such as a gripper assembly) to the material handling system 104. The material handling system 104 moves workpieces 102a1 (e.g., using a conveyor assembly, using a gripper assembly, etc.) from the input workpiece supply unit 102 to a support structure 106. During the welding operation, the support structure 106 supports the workpieces (now labeled as using...) Figure 5The workpiece 102a2 shown is clamped against the support structure 106 when the workpiece clamp 108 is clamped. After the welding operation (described below with respect to the welding head assembly 112), the now-welded workpiece 102a3 is moved from the downstream portion of the material handling system 104 of the support structure 106 (e.g., using a conveyor assembly, using a gripper assembly, etc.) to the output workpiece supply unit 110. The output workpiece supply unit 110 is configured to receive the welded workpiece 102a3 after being processed by the welding head assembly 112 (wherein the welding head assembly 112 includes an ultrasonic transducer 112b carrying the ultrasonic welding electrode 202). The output workpiece supply unit 110 may be a carrier such as a storage transporter for carrying multiple welded workpieces 102a3, or another supply structure suitable for application-specific workpieces.

[0013] The ultrasonic welding system 100 includes a welding head assembly 112. The welding head assembly includes an ultrasonic transducer 112b carrying an ultrasonic welding electrode 202, and the welding head assembly is movable along multiple generally horizontal axes. Figure 1 In the example shown, the welding head assembly 112 is configured to move along the x-axis and y-axis of the ultrasonic welding system 100. Figure 1 In the example shown, the welding head assembly 112 is also configured to move along the z-axis of the ultrasonic welding system 100 and about the θ-axis (Ø-axis) of the ultrasonic welding system 100. Not every application requires all of these axes of motion. Using the axes of motion of the welding head assembly 112, the ultrasonic welding electrode 202 can be moved to the correct welding position relative to the clamped workpiece 102a2. A camera 114 is also provided (where the camera may optionally be carried by the welding head assembly 112, or may be carried by another part of the ultrasonic welding system 100) for imaging operations related to alignment between the ultrasonic welding electrode 202 and the clamped workpiece 102a2, alignment of components of the clamped workpiece 102a2 itself, optical inspection of the weld after the welding operation, etc.

[0014] Various types of workpieces can be welded using the ultrasonic welding system 100 (or other systems within the scope of this invention). Exemplary workpieces include power modules, lead frames, and battery modules.

[0015] According to the present invention, various types of ultrasonic motion can be applied to conductors (e.g., conductive pins, signal connectors, conductive terminals, power terminals, etc.). For example, an ultrasonic welding electrode can be configured to weld the conductor to a workpiece using at least one of linear ultrasonic motion and torsional ultrasonic motion.

[0016] Some of these workpieces are configured to receive conductive pins. As used herein, the term "conductive pin" is a conductive structure intended to be welded to a workpiece. A conductive pin may have a free end (after welding to the workpiece), and the body portion of the conductive pin may extend generally vertically from the "welded" end to the free end. The cross-section of a conductive pin may be circular, square, rectangular, or have any desired cross-section. The term conductive pin should also be interpreted as including a conductive housing or sleeve (e.g., tubular) wherein the conductive housing / sleeve is ultrasonically welded to the workpiece and configured to receive another conductive element. According to certain exemplary embodiments of the invention, an ultrasonic welding system 100 includes a conductive pin supply 200 configured to provide a plurality of conductive pins for welding using an ultrasonic welding electrode 202. Exemplary configurations of the conductive pin supply include: a grid arrangement structure (including rows and columns of conductive pins oriented in an easily pick-up manner), a bowl feeder, a hopper, a spool, etc. Alternative configurations are also considered. The conductive pin supply unit 200 can be configured to operate together with a buffer system so that pins are fed through a staging area and ready to be picked up for soldering.

[0017] The ultrasonic welding system 100, including the conductive pin supply section 200 and the ultrasonic welding electrode 202, can take various forms. More specifically, different configurations of the conductive pin supply section 200 and different configurations of the ultrasonic welding electrode 202 are also considered. Figure 2A-2C The figure illustrates an exemplary ultrasonic welding system 100a, which includes a conductive pin supply section (hereinafter referred to as conductive pin supply section 200a including conductive pin 200a) configured in an exemplary configuration and an ultrasonic welding electrode (hereinafter referred to as ultrasonic welding electrode 202a, which defines a vacuum channel 202a and is connected to a vacuum source 204 via a conduit 204a). Figures 3A-3C The figure illustrates an exemplary ultrasonic welding system 100b, which includes a conductive pin supply section (hereinafter referred to as conductive pin supply section 200b including conductive pin 200bl) configured in another exemplary configuration and an ultrasonic welding electrode (hereinafter referred to as ultrasonic welding electrode 202b, which is adapted to work with gripper actuator 206 and gripper arm 206a) configured in an exemplary configuration. Figure 4 The figure also illustrates another exemplary ultrasonic welding system 100c, which is substantially similar to ultrasonic welding system 100b (in... Figures 3A-3C In addition to the ultrasonic welding system 100c including a gripper actuator 208, a first gripper arm 208a, and a second gripper arm 208b, each of the ultrasonic welding systems 100a, 100b, and 100c is substantially similar to the ultrasonic welding system 100 described above, except that the ultrasonic welding systems 100a, 100b, and 100c are (different from) those described herein.

[0018] For details, please refer to the following: Figure 2A-2C The ultrasonic welding electrode 202a is configured to extract conductive pins 200a1 from the conductive pin supply section 200a, and the welding head assembly 112 is configured (through its different axes of motion) to carry the extracted conductive pins 200a1 toward the clamped workpiece 102a2 and to ultrasonically weld the conductive pins 200a1 to the clamped workpiece 102a2. The ultrasonic welding electrode 202a defines a vacuum channel 202a1 connected via a conduit 204a to a vacuum source 204 for extracting the conductive pins 200a1 from the conductive pin supply section 200a.

[0019] For details, please refer to the following: Figure 2B The end portion 202a3 of the ultrasonic welding electrode 202 is shown. A vacuum channel 202a1 is defined by the ultrasonic welding electrode 202a. The working surface 202a2 of the ultrasonic welding electrode 202a is configured to contact the welding portion of the conductive pin and press it against the workpiece for ultrasonic welding (see, for example, [reference needed]). Figure 2C The soldering portion of the conductive pin shown. Vacuum hole 202a4 of ultrasonic solder electrode 202a (configured for use with, as shown) Figure 2A The pipe 204a joint shown is also illustrated. Figure 2C This is a side view of a conductive pin 200al (e.g., a circular conductive pin), which includes a body portion 200ala, a solder portion 200alb, and a free end 200alc. After being soldered to a workpiece via the solder portion 200alb, the body portion 200ala may extend generally vertically from the solder portion 200alb to the free end 200alc. The free end 200alc (or some other portion of the soldered conductive pin 200al) can be used for the required electrical connection in a given workpiece.

[0020] For details, please refer to the following: Figures 3A-3C The welding head assembly 112 includes a gripper mechanism configured to remove the conductive pin 200bl from the conductive pin supply section 200b. Figure 3A In this gripper mechanism, there are gripper actuators 206 and movable arms 206a. Actuation of the gripper actuator 206 configures the movable arm 206a to move between (i) an open position and (ii) a closed position, the open position being as follows: Figure 3B The diagram shows the connection of the conductive pin 200bl, and the closed position is as follows: Figure 3C The diagram shows a position for holding the conductive pin 200b1 in order to move toward the clamped workpiece 102a2. Figure 3BAs shown, in the closed position, the movable arm 206a aligns the conductive pin 200b1 with the ultrasonic welding electrode 202b, holding the conductive pin 200b1 in place relative to the ultrasonic welding electrode 202b. The welding head assembly 112 is configured to transport the removed conductive pin 200b1 toward the workpiece and ultrasonically weld the conductive pin 200b1 to the clamped workpiece 102a2.

[0021] For details, please refer to the following: Figure 4 The welding head assembly 112 includes another gripper mechanism configured to remove the conductive pin 200bl from the conductive pin supply section 200b. Figure 4 The gripper mechanism includes a gripper actuator 208, a movable arm 208a, and a fixed arm 208b. Actuation of the gripper actuator 208 configures the movable arm 208a to move between an (i) open position and an (ii) closed position, the open position for engaging the conductive pin 200b1, and the closed position for holding the conductive pin 200b1 in a position for movement toward the clamped workpiece 102a2. Figure 4 As shown, the movable arm 208a moves to hold the conductive pin 200b1 against the fixed arm 208b in a closed position, thereby aligning the conductive pin 200b1 with the ultrasonic welding electrode 202b. The welding head assembly 112 is configured to transport the removed conductive pin 200b1 toward the clamped workpiece 102a2 and to ultrasonically weld the conductive pin 200b1 to the clamped workpiece 102a2.

[0022] For details, please refer to the following: Figures 3A-3C and Figure 4 In detail Figure 3D The conductive pin 200bl shown has a connection with the one from the source. Figure 2A-2C The conductive pin 200a1 has a different configuration compared to the conductive pin 200b1. The conductive pin 200b1 includes a body portion 200b1a, a solder portion 200b1b, and a free end 200b1c. After being soldered to the workpiece via the solder portion 200b1b, the body portion 200b1a can extend generally vertically from the solder portion 200b1b to the free end 200b1c. The free end 200b1c (or some other portion of the soldered conductive pin 200b1) can be used for the required electrical connection in a given workpiece.

[0023] It will be understood that while aspects of the invention specifically relate to ultrasonic welding systems for soldering conductive leads to workpieces, the invention is not limited thereto. For example, according to certain exemplary embodiments of the invention, ultrasonic welding electrodes are configured for soldering conductive leads to workpieces, as well as for soldering other conductors (e.g., conductive terminals such as power terminals) to workpieces. The ultrasonic welding electrode can use a single working area (e.g., such as...) Figure 2B The working surface 202a2 shown is used to weld both conductive pins and other conductors such as power terminals. However, in other embodiments of the invention, the ultrasonic welding electrode includes a first region and a second region, the first region being configured to contact the conductive pins for welding to the workpiece, and the second region being configured to contact the power terminals for welding to the workpiece.

[0024] In other exemplary embodiments of the invention, the ultrasonic welding system includes a second welding head assembly having a second ultrasonic transducer carrying a second ultrasonic welding electrode, the second welding head assembly being configured to weld power terminals to a workpiece. See details. Figure 5 An ultrasonic welding system 500 is shown. The ultrasonic welding system 500 includes a first ultrasonic welding subsystem 502 (which may be substantially similar to that in International Publication No. 2018 / 187364). Figure 1 The ultrasonic welding system 100 shown herein is similar to the welding system disclosed herein, except that the first ultrasonic welding subsystem 502 includes an ultrasonic welding electrode 112a but does not include a conductive pin supply section, and the second ultrasonic welding subsystem 504. The second ultrasonic welding subsystem 504 can be, for example... Figure 1 The ultrasonic welding system 100 shown Figure 2A The ultrasonic welding system 100a shown is Figure 3A The ultrasonic welding system 100b shown Figure 4 The ultrasonic welding system 100c shown herein, etc., is an example. The first ultrasonic welding subsystem 502 is configured to weld certain conductors (e.g., larger power conductors, such as power supply terminal 506), while the second ultrasonic welding subsystem 504 is configured to weld conductive pins, as described herein. Figure 5 An example of an output workpiece 102a3' of an ultrasonic welding system 500 is shown. The output workpiece 102a3' includes a substrate (not labeled), conductive terminals 506 ultrasonically welded to the substrate, and conductive pins 200a1 ultrasonically welded to the substrate. For example, workpiece 102a3' may be a power semiconductor module, wherein conductive terminals 506 are power supply terminals of the power semiconductor module, and wherein conductive pins 200a1 are signal connection portions of the power semiconductor module.

[0025] although Figure 5 The diagram illustrates a conductive pin supply section 200a including a conductive pin 200a1 (i.e., similar to...). Figure 2A The configuration configuration in the present invention), but the inventive features of the ultrasonic welding system 500 (including the ultrasonic welding system 504) can also be applied to any type of conductive pin within the scope of the present invention (e.g., Figure 3A The conductive pin 200bl shown, and the corresponding changes to the solder head assembly.

[0026] According to certain exemplary embodiments of the present invention, during the welding operation, exemplary technical specifications include: (i) the ultrasonic welding electrode is configured to operate with a bonding force between 5 and 500 kg, or the ultrasonic welding electrode is configured to operate with a bonding force between 5 and 300 kg, or the ultrasonic welding electrode is configured to operate with a bonding force between 5 and 100 kg; (ii) the ultrasonic welding electrode tip movement amplitude is between 5 and 150 micrometers, or the ultrasonic welding electrode tip movement amplitude is between 5 and 120 micrometers, or the ultrasonic welding electrode tip movement amplitude is between 5 and 100 micrometers; (iii) the ultrasonic welding electrode is configured to form a gap of 1.5-30 mm between a first portion and a second portion of the workpiece. 2 An ultrasonic welded portion with an area within a certain range; or an ultrasonic welding electrode configured to form an area of ​​1.5-20 mm between a first part and a second part of the workpiece. 2 An ultrasonic welded portion with an area within a certain range; or an ultrasonic welding electrode configured to form an area of ​​1.5-16 mm between a first part and a second part of a workpiece. 2 The ultrasonic welded portion has an area within the range of (iv) 15-40 kHz, or 20-35 kHz, or the ultrasonic electrode is configured to operate at a frequency within the range of 20-30 kHz. Exemplary thicknesses of the conductive contacts (the portion of the workpiece contacted by the ultrasonic welding electrode) of the contact element include: 0.2-3 mm; 0.2-1.5 mm; and 0.2-1.2 mm.

[0027] Variations within the scope of this invention are also considered, even if not illustrated. For example, according to certain exemplary embodiments of the invention, the welding head assembly may define a key connection feature configured to align with a corresponding key connection feature of a conductive pin such that the conductive pin held by the welding head assembly is correctly aligned with respect to the ultrasonic welding electrode. Figures 6A-6D and Figure 6E-6G The figure illustrates an example of such an embodiment of the invention. Figures 6A-6D and Figure 6E-6G The conductive pins and ultrasonic welding electrodes may be implemented in conjunction with any ultrasonic welding system disclosed herein (e.g., ultrasonic welding systems 100, 100a, 100b, 100c, 504, and 700) or any other ultrasonic welding system within the scope of this invention.

[0028] Figure 6A and Figure 6BThe figures are a side view and a top view of a conductive pin 600a1 (e.g., a circular conductive pin), which includes a body portion 600a1, a weld portion 600a1b, a free end 600a1c, and a key connection feature 600a1d. The key connection feature 600a1d of the conductive pin 600a1 can be used to align with a corresponding key connection feature (e.g., a keyway) of the weld head assembly such that the conductive pin 600a1 held by the weld head assembly is correctly aligned relative to the ultrasonic welding electrode 602a. After welding to a workpiece via the weld portion 600a1b, the body portion 600a1 can extend generally vertically from the weld portion 600a1b to the free end 600a1c. The free end 600a1c (or some other portion of the welded conductive pin 600a1) can be used for the desired electrical connection in a given workpiece. Figure 6C This is an end view of an ultrasonic solder electrode 602a, which includes a vacuum channel 602al defined by the ultrasonic solder electrode 602a. At the vacuum channel 602al, the ultrasonic solder electrode 602a defines a bonding feature 602ald (e.g., a recess). When a conductive pin 600ald engages with the ultrasonic solder electrode 602a, the bonding feature 600ald engages with the bonding feature 602ald. Figure 6D A conductive pin 600al is shown aligned with the ultrasonic welding electrode 602a relative to the welding head assembly (not shown, but see welding head assembly 112 throughout the figures).

[0029] Figure 6E and Figure 6F The images show a side view and a top view of a conductive pin 600bl (e.g., a conductive pin with an "L" shape), which includes a body portion 600bla, a solder portion 600blb, a free end 600blc, and a keying feature 600bld (e.g., a protrusion). The keying feature 600bld of the conductive pin 600bl can be used with a gripper arm 206a' (similar to...). Figures 3A-3C The corresponding key connection features (e.g., keyways) of the gripper arm 206a are aligned such that the conductive pin 600b1 is held in place by the gripper arm 206a' of the welding head assembly, thereby aligning the conductive pin 600b1 relative to the ultrasonic welding electrode 602a. After welding to the workpiece via the welding portion 600blb, the body portion 600bla can extend generally vertically from the welding portion 600b1b to the free end 600blc. The free end 600blc (or some other portion of the welded conductive pin 600bl) can be used for the desired electrical connection in a given workpiece. Figure 6GThis is a top view of the gripper arm 206a' engaging with the conductive pin 600b2. The gripper arm 206a' defines a key connection feature 206a'l (i.e., a recess). When the conductive pin 600b2 engages with the gripper arm 206a', the key connection feature 206a'l engages with the key connection feature 602bld.

[0030] Combination Figure 6A-6G The key connection features illustrated and described are exemplary in nature; alternative key connection features or alignment features may also be considered within the scope of the invention. For example, key connection feature 600ald protrudes from the body portion 600ala of conductive pin 600al; however, recessed key connection features may also be employed in connection with such conductive pins, wherein the key connection features mating with ultrasonic solder electrodes (or other portions of the bonding head assembly) may be prominent features.

[0031] Furthermore, according to certain exemplary embodiments of the invention, the ultrasonic welding electrode (or other aspects of the welding head assembly, such as the gripper mechanism) may not be used as a pick-up tool. Instead, the ultrasonic welding system may further include a pick-up tool configured to remove conductive pins from a conductive pin supply, wherein the removed conductive pins are passed to the welding head assembly for welding to the workpiece.

[0032] For details, please refer to the following: Figure 7 An ultrasonic welding system 700 is shown. The ultrasonic welding system 700 (which is similar to the aforementioned ultrasonic welding system described herein) includes a pickup tool 702. The pickup tool 702 includes a contact portion 702a. According to certain exemplary embodiments of the invention, the pickup tool 702 retrieves (or otherwise receives) a conductive pin 200a1 from a conductive pin supply 200a. The conductive pin 200a1 is passed to a welding head assembly 112 for welding to a workpiece 102a2. The contact portion 702a may have a variety of different alternative configurations for picking up the conductive pin 200a1 from the conductive pin supply 200a and engaging it in the ultrasonic welding electrode 202a that passes the conductive pin 200a1 to the welding head assembly 112. Exemplary configurations of the contact portion 702a include: a magnetic holding mechanism; a mechanical gripping mechanism; a vacuum-based holding mechanism, etc.

[0033] Refer again Figure 7After the pickup tool 702 holds the conductive pin 200a1, the pickup tool 702 can move toward the ultrasonic soldering electrode 202a to facilitate the transfer of the conductive pin 200a1 (see the dashed portion of the conductive pin 200a1 engaged with the ultrasonic soldering electrode 202). Alternatively, the ultrasonic soldering electrode 202a (carried by the soldering head assembly 112) can move toward the pickup tool 702 to facilitate the transfer of the conductive pin 200a1. In yet another alternative embodiment, both the pickup tool 702 and the ultrasonic soldering electrode 202a can move toward each other to facilitate the transfer of the conductive pin 200a1. Although Figure 7 The diagram shows a conductive pin supply section 200a including conductive pin 200a1 (i.e., similar to...). Figure 2A (the configuration configuration in the text), however, the inventive features of the ultrasonic welding system 700 can also be applied to any type of conductive pin within the scope of the invention (e.g., Figure 3A The conductive pin 200bl shown, and the corresponding changes to the solder head assembly.

[0034] Although the invention has been illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made to the details within the scope of the claims and their equivalents, without departing from the invention.

Claims

1. An ultrasonic welding system, comprising: A support structure configured to support a workpiece; A welding head assembly, the welding head assembly including an ultrasonic transducer carrying an ultrasonic welding electrode; as well as A conductive pin supply section is configured to provide a plurality of conductive pins for welding using the ultrasonic welding electrode.

2. The ultrasonic welding system of claim 1, wherein, The ultrasonic welding electrode of the welding head assembly is configured to extract a conductive pin from the conductive pin supply section, and the welding head assembly is configured to transport the extracted conductive pin toward the workpiece and ultrasonically weld the conductive pin to the workpiece.

3. The ultrasonic welding system of claim 1, wherein, The welding head assembly includes a gripper mechanism configured to remove conductive pins from the conductive pin supply section, and the welding head assembly is configured to transport the removed conductive pins toward the workpiece and ultrasonically weld the conductive pins to the workpiece.

4. The ultrasonic welding system according to claim 3, wherein, The gripper mechanism includes a movable arm and a fixed arm, the movable arm being configured to move between an (i) open position and a (ii) closed position, the open position being for engaging a conductive pin and the closed position being for holding the conductive pin in a position for movement toward a workpiece, wherein the movable arm aligns the conductive pin with an ultrasonic welding electrode in the closed position.

5. An ultrasonic welding system, comprising: A support structure configured to support a workpiece; A welding head assembly, the welding head assembly including an ultrasonic transducer carrying an ultrasonic welding electrode; as well as A conductive pin supply section, configured to provide a plurality of conductive pins for welding using the ultrasonic welding electrode. The welding head assembly includes a gripper mechanism configured to extract conductive pins from the conductive pin supply section, and the welding head assembly configured to transport the extracted conductive pins toward the workpiece and ultrasonically weld the conductive pins to the workpiece. The gripper mechanism includes a movable arm configured to move between (i) an open position and (ii) a closed position, the open position for engaging a conductive pin and the closed position for holding the conductive pin in a position for movement toward a workpiece.

6. The ultrasonic welding system according to claim 5, wherein, The movable arm aligns the conductive pin with the ultrasonic welding electrode in the closed position.

7. An ultrasonic welding system, comprising: A support structure configured to support a workpiece; A welding head assembly, the welding head assembly including an ultrasonic transducer carrying an ultrasonic welding electrode; as well as A conductive pin supply section, configured to provide a plurality of conductive pins for welding using the ultrasonic welding electrode. The ultrasonic welding electrode of the welding head assembly is configured to extract a conductive pin from the conductive pin supply section, and the welding head assembly is configured to transport the extracted conductive pin toward the workpiece and ultrasonically weld the conductive pin to the workpiece, wherein the ultrasonic welding electrode defines a vacuum channel for extracting the conductive pin from the conductive pin supply section.

8. The ultrasonic welding system according to any one of claims 1 to 7, wherein, The welding head assembly is configured to move along multiple dissimilar axes of motion.

9. The ultrasonic welding system according to any one of claims 1 to 7, wherein, The welding head assembly is configured to move along multiple disparate axes of motion, including an x-axis, a y-axis, and a z-axis.

10. The ultrasonic welding system according to any one of claims 1 to 7, wherein, The welding head assembly is configured to move along multiple disparate axes of motion, including the θ axis.

11. The ultrasonic welding system according to any one of claims 1 to 7, further comprising a pickup tool configured to remove a conductive pin from the conductive pin supply, the removed conductive pin being passed to the welding head assembly for welding to a workpiece.

12. The ultrasonic welding system according to any one of claims 1 to 7, wherein, The ultrasonic welding electrode is configured to weld conductive pins to a workpiece and to weld power terminals to a workpiece.

13. The ultrasonic welding system according to any one of claims 1 to 7, wherein, The ultrasonic welding electrode includes a first region and a second region, the first region being configured to contact a conductive pin for welding to a workpiece, and the second region being configured to contact a power terminal for welding to a workpiece.

14. The ultrasonic welding system according to any one of claims 1 to 7, further comprising a second welding head assembly, the second welding head assembly including a second ultrasonic transducer carrying a second ultrasonic welding electrode, the second welding head assembly being configured to weld power terminals to a workpiece.

15. A method for operating an ultrasonic welding system, the method comprising the following steps: The workpiece is supported on the support structure of the ultrasonic welding system; and Using the ultrasonic welding electrode of the welding head assembly of an ultrasonic welding system, conductive pins from a conductive pin supply unit of the ultrasonic welding system are welded to a workpiece, the conductive pin supply unit including a plurality of conductive pins.

16. The method according to claim 15, wherein, Prior to the welding step, the method further includes the following steps: (i) removing conductive pins from the conductive pin supply using the ultrasonic welding electrode of the welding head assembly, and (ii) transporting the removed conductive pins toward the workpiece using the welding head assembly.

17. The method according to claim 15, wherein, The welding head assembly includes a gripper mechanism, and the method further includes the steps of: (i) using the gripper mechanism to remove a conductive pin from the conductive pin supply section, and (ii) using the welding head assembly to transport the removed conductive pin toward the workpiece.

18. The method according to claim 17, wherein, The gripper mechanism includes a movable arm and a fixed arm, the movable arm being configured to move between an (i) open position and a (ii) closed position, the open position being for engaging a conductive pin and the closed position being for holding the conductive pin in a position for movement toward a workpiece, wherein the movable arm aligns the conductive pin with an ultrasonic welding electrode in the closed position.

19. A method of operating an ultrasonic welding system, the method comprising the following steps: The workpiece is supported on the support structure of the ultrasonic welding system; and Using the ultrasonic welding electrode of the welding head assembly of an ultrasonic welding system, conductive pins from the conductive pin supply unit of the ultrasonic welding system are welded to the workpiece. The conductive pin supply unit includes multiple conductive pins. The welding head assembly includes a gripper mechanism, and the method further includes the steps of: (i) using the gripper mechanism to remove a conductive pin from the conductive pin supply section, and (ii) using the welding head assembly to transport the removed conductive pin toward the workpiece. The gripper mechanism includes a movable arm configured to move between (i) an open position and (ii) a closed position, the open position for engaging a conductive pin and the closed position for holding the conductive pin in a position for movement toward a workpiece.

20. The method according to claim 19, wherein, The movable arm aligns the conductive pin with the ultrasonic welding electrode in the closed position.

21. A method for operating an ultrasonic welding system, the method comprising the following steps: The workpiece is supported on the support structure of the ultrasonic welding system; and Using the ultrasonic welding electrode of the welding head assembly of an ultrasonic welding system, a conductive pin is taken out from a conductive pin supply section, the ultrasonic welding electrode defining a vacuum channel for taking out the conductive pin from the conductive pin supply section, the conductive pin supply section including a plurality of conductive pins; Using the welding head assembly, the extracted conductive pins are transported toward the workpiece; as well as Using the ultrasonic welding electrode of the welding head assembly of the ultrasonic welding system, conductive pins from the conductive pin supply section of the ultrasonic welding system are welded to the workpiece.

22. The method according to any one of claims 15 to 21, wherein, The welding head assembly is configured to move along multiple dissimilar axes of motion of the ultrasonic welding system.

23. The method according to any one of claims 15 to 21, wherein, The welding head assembly is configured to move along multiple disparate axes of motion of the ultrasonic welding system, wherein the multiple disparate axes of motion include the x-axis, y-axis and z-axis.

24. The method according to any one of claims 15 to 21, wherein, The welding head assembly is configured to move along multiple disparate axes of motion, including the θ axis.

25. The method according to any one of claims 15 to 21, further comprising the step of: (i) Using a pick-up tool, a conductive pin is removed from the conductive pin supply section, and (ii) the conductive pin is transferred from the pick-up tool to the welding head assembly for welding to the workpiece.

26. The method according to any one of claims 15 to 21, further comprising the step of: The power terminals are welded to the workpiece using the ultrasonic welding electrode.

27. The method according to any one of claims 15 to 21, further comprising the step of: Using the ultrasonic welding electrode, power terminals are welded to a workpiece, wherein the ultrasonic welding electrode includes a first region and a second region, the first region being configured to contact a conductive pin for welding to the workpiece, and the second region being configured to contact a power terminal for welding to the workpiece.

28. The method according to any one of claims 15 to 21, wherein, The ultrasonic welding system includes a second welding head assembly, the second welding head assembly includes a second ultrasonic transducer carrying a second ultrasonic welding electrode, and the method further includes the step of welding a power terminal to a workpiece using the second ultrasonic welding electrode.

29. A workpiece comprising: substrate; as well as Conductive pins are ultrasonically welded to the substrate.

30. The workpiece according to claim 29, further comprising a conductive terminal ultrasonically welded to the substrate.

31. The workpiece according to claim 30, wherein, The conductive terminal is the power terminal of the workpiece, and the conductive pin is the signal connection part of the workpiece.

32. The workpiece according to claim 29, wherein, The workpiece is a power semiconductor module.

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