TWI817330B - Wire bonding device, control method of wire bonding device, and control program of wire bonding device - Google Patents

Abstract

The present invention provides a wire bonding device that can prevent bonding from being performed when an airless ball is eccentric. The wire bonding device includes: a porcelain nozzle, which supplies the bonding wire; an air torch, which forms an air-free balloon at the end of the bonding line protruding from the porcelain nozzle; and a camera unit, which takes pictures of the air-free balloon formed at the front end by the air torch a line tail; and a measuring unit that measures the deflection of the airless balloon relative to the central axis of the bonding line based on the image output from the imaging unit.

Description

Wire bonding device, control method of wire bonding device, and control program of wire bonding device

The present invention relates to a wire bonding device, a control method of the wire bonding device, and a control program of the wire bonding device.

In a wire bonding device, it is important to stabilize the shape of the Free Air Ball (FAB). For example, according to Patent Document 1, a stable FAB is formed by studying the composition of a bonding wire. [Prior technical literature] [Patent Document]

Patent Document 1: Japanese Patent No. 5807992

[Problem to be solved by the invention]

There are various types of bonding wires used in wire bonding devices, and most of them are used differently depending on the purpose. Therefore, it is a big limitation that only bonding wires with a specific composition can be used. In addition, factors such as environmental temperature, lead diameter, and wire tail length may also affect the eccentricity of the airless balloon relative to the lead axis, not limited to the composition. The eccentricity of the airless balloon will cause the eccentricity of the press ball, which may cause short circuits between the pad electrodes and other defects.

The present invention is made in order to solve this problem, and provides a wire bonding device and the like that can prevent bonding from being performed in a state where the airless ball is eccentric. [Means to solve the problem]

A wire bonding device according to a first aspect of the present invention includes: a porcelain nozzle for supplying a bonding wire; a torch for forming an airless balloon on the wire tail of the bonding wire extending from the porcelain nozzle; and a camera unit, A method for photographing the line tail with an airless balloon formed at the front end by a gas torch; and a measuring section for measuring a displacement of the airless balloon relative to the central axis of the bonding line based on an image output from the imaging section.

The control method of the wire bonding device of the second aspect of the present invention includes: a wire tail forming step, extending the bonding wire from the front end of the porcelain nozzle to form a wire tail; and an airless balloon forming step, using an air torch on the front end of the wire tail forming an airless balloon at the end; a photographing step of photographing the end of the line formed with the airless balloon; and a measuring step of measuring the offset of the airless balloon relative to the central axis of the joint line based on the image output in the photographing step.

The control program of the wire bonding device of the third aspect of the present invention causes the computer to execute: the wire tail forming step, extending the bonding wire from the front end of the porcelain nozzle to form the wire tail; and the airless balloon forming step, using an air torch to form the wire tail. An airless balloon is formed at the front end of the line; the imaging step is to photograph the line tail formed with the airless balloon; and the measuring step is to measure the offset of the airless balloon relative to the central axis of the joint line based on the image output in the imaging step. [Effects of the invention]

According to the wire bonding apparatus and the like of the present invention, an airless ball can be formed in a manufacturing environment where semiconductor wafers are actually manufactured and its eccentricity can be measured immediately, thereby preventing bonding from being performed in an eccentric state of the airless ball.

Hereinafter, the present invention will be described based on the embodiments of the invention. However, the invention described in the claimed scope is not limited to the following embodiments. In addition, not all the structures described in the embodiments are necessary as means to solve the problems.

FIG. 1 is a perspective view schematically showing the main parts of the wire bonding machine 100 according to this embodiment. The illustrated wire bonding machine 100 uses a simplified structure or mechanism for the sake of understanding, or makes the size or shape of the elements different, or omits elements not directly related to the present embodiment, but this is not meant to represent actual wire bonding. machine differences.

The wire bonding machine 100 is a bonding device that connects a pad electrode 321 of a semiconductor chip 320 and a lead electrode 322 of a substrate 330 through a wire 300 serving as a bonding wire. The wire bonding machine 100 mainly includes a head 110, a tool part 120, a gas torch 131, a porcelain nozzle 133, a first camera unit 151, and a second camera unit 152. The head 110 supports the tool part 120, the gas torch 131, the first imaging unit 151, and the second imaging unit 152, and is movable in the plane direction by the head drive motor 141. As shown in the figure, the plane direction is the horizontal direction defined by the X-axis direction and the Y-axis direction, and is also the moving direction of the platform 220 placed on the stand 210. The substrate 330 is placed and fixed on the platform 220 .

The tool part 120 supports a clamp 132 and a transducer 134 respectively extending along the Y-axis direction, and a porcelain nozzle 133 is provided at the front end of the transducer 134 . The wire clamp 132 has a hand for clamping the lead wire 300 , and clamps and releases the lead wire 300 according to the control of the wire bonding machine 100 . The transducer 134 applies ultrasonic vibration to the vicinity of the front end of the lead wire 300 through the porcelain nozzle 133 during bonding. The ceramic nozzle 133 functions to guide the lead wire 300 and supply it to the pad electrode 321 and the lead electrode 322, and to press the tip end of the lead wire 300 against the pad electrode 321 and the lead electrode 322 during bonding. The lead wire 300 is supplied from a lead wire supply unit (not shown) including a tensioner or a rotating spool. The material of the lead 300 is appropriately selected according to the type or properties of the semiconductor wafer 320 , and for example, gold, silver, or copper is used.

The gas torch 131 is supported on the head 110 and includes a discharge electrode at the front end. During the first bonding to the pad electrode 321, a lead wire 300 of a certain length is extended from the front end of the porcelain nozzle 133 to form a wire tail. In this state, the front end of the line tail faces the electrode of the gas torch 131 along the X-axis direction. As shown in the figure, a free air ball (FAB) 301 in a molten state is formed by applying a voltage to the electrode. . The tool part 120 can move in the height direction relative to the head 110 by the tool driving motor 142, so that the front end of the wire tail can face the electrode of the gas torch 131, or can be closer to or farther away from the pad electrode 321 or the wire electrode 322. . As shown in the figure, the height direction is the Z-axis direction orthogonal to the plane direction.

The first imaging unit 151 is an imaging unit for imaging the FAB 301 formed at the front end of the line tail from the Y-axis direction, and is supported by the head 110 . The first camera unit 151 includes: a camera element that outputs an image signal; and an optical system that forms the image of the FAB 301 on the camera element. The second imaging unit 152 is an imaging unit for imaging the FAB 301 formed at the front end of the line tail from the X-axis direction, and is supported on the head 110 like the first imaging unit 151 . The second camera unit 152 also includes: a camera element that outputs an image signal; and an optical system that forms the image of the FAB 301 on the camera element. In the following description, the first imaging unit 151 and the second imaging unit 152 may be collectively referred to as an imaging unit.

Furthermore, the XYZ coordinate system is a spatial coordinate system with the reference position of the head 110 as the origin. In the following drawings, the same coordinate axes may also be described in order to indicate the direction of each element.

FIG. 2 is a system structure diagram of the wire bonding machine 100. The control system of the wire bonding machine 100 mainly includes a calculation processing unit 170, a memory unit 180, an input and output device 190, a gas torch 131, a wire clamp 132, a converter 134, a head drive motor 141, a tool drive motor 142, and a first camera unit 151 and the second camera unit 152. The arithmetic processing unit 170 is a processor (Central Processing Unit (CPU)) that controls the wire bonding machine 100 and executes programs. The processor can also be a structure that cooperates with computing processing chips such as Application Specific Integrated Circuit (ASIC) or Graphics Processing Unit (GPU). The arithmetic processing unit 170 reads the control program stored in the memory unit 180 and executes various processes related to the joining.

The memory unit 180 is a non-volatile memory medium, including, for example, a hard disk drive (HDD). The memory unit 180 may store not only programs for executing control or processing of the wire bonding machine 100 , but also various parameter values, functions, look-up tables, etc. used for control or calculation. The input/output device 190 includes, for example, a keyboard, a mouse, and a display monitor, and is a device that accepts menu operations performed by the user or prompts information to the user. For example, the arithmetic processing unit 170 may display the measurement result of the FAB together with the captured image on a display monitor that is one of the input and output devices 190 .

When the gas torch 131 receives the discharge instruction signal from the arithmetic processing unit 170, it executes voltage application to the electrodes. When the voltage is applied to the electrode, arc discharge occurs between the electrode and the wire tail, and FAB is formed at the tip of the wire tail. The wire clamp 132 closes the hand while receiving the clamping instruction signal from the arithmetic processing unit 170 . If the clamping indication signal is released, open the hand. When the hand is closed, the lead 300 does not extend from the porcelain mouth 133 or is not pulled back toward the porcelain mouth 133 . When the converter 134 receives the excitation signal from the arithmetic processing unit 170, it causes the vibrator to vibrate. The ultrasonic vibrations caused by transducer 134 facilitate bonding of lead 300 .

The head drive monitor 141 receives a drive signal from the arithmetic processing unit 170 to move the head 110 in the plane direction. The tool driving motor 142 receives a driving signal from the processing unit 170 to move the tool unit 120 in the height direction.

The first imaging unit 151 receives the imaging request signal from the arithmetic processing unit 170, performs imaging, and sends the first image output by the imaging element to the arithmetic processing unit 170 in the form of an image signal. Similarly, the second imaging unit 152 receives the imaging request signal from the arithmetic processing unit 170, performs imaging, and sends the second image output by the imaging element to the arithmetic processing unit 170 in the form of an image signal.

The arithmetic processing unit 170 also plays a role as a functional arithmetic unit and performs various operations according to processing instructed by the control program. The arithmetic processing unit 170 functions as the measurement unit 171 , the adjustment unit 172 , and the drive control unit 173 . The measurement unit 171 sends a shooting request signal to the first camera unit 151 and the second camera unit 152, acquires the image signal of the first image and the image signal of the second image, and measures the deviation of the FAB relative to the central axis of the lead 300. shift. The adjustment unit 172 adjusts the discharge conditions of the gas torch 131 based on the measurement results obtained by the measurement unit 171 . The drive control unit 173 generates a drive signal for driving the head drive motor 141 and a drive signal for driving the tool drive motor 142, and sends them to each motor.

FIG. 3 is a diagram explaining the observation status of FAB. As mentioned above, the lead wire 300 extends from the front end of the porcelain nozzle 133 to form a wire tail. The front end of the wire tail receives arc discharge from the gas torch 131 from the positive direction of the X-axis to form the FAB 301.

Regarding the FAB 301 , depending on the discharge conditions of the gas torch 131 , the FAB 301 may be formed to be offset from the central axis of the lead wire 300 . If the amount of deviation exceeds the allowable amount, the crimp ball formed on the pad electrode 321 during the first bonding may be eccentric, resulting in defects such as a short circuit between the pad electrodes 321 . The offset of FAB301 is caused by various factors such as the composition or diameter of the lead 300, the length of the wire tail, and the ambient temperature. Therefore, it is preferable to form FAB 301 under the conditions of actually executing the wiring operation and evaluate whether the offset exceeds the allowable amount. In addition, even when the offset amount exceeds the allowable amount, it may be possible to suppress it below the allowable amount by adjusting the discharge conditions of the gas torch 131 . Therefore, the wire bonding machine 100 of this embodiment photographs the FAB 301 actually formed and measures its offset.

The first imaging unit 151 is arranged to capture the line tail including the FAB 301 from the Y-axis direction, which is the Z-axis direction as the extension direction of the line tail from the porcelain nozzle 133 and the arc discharge direction. The discharge direction is orthogonal to the X-axis direction. The first camera unit 151 generates an image signal of a first image obtained by photographing the line end in the Y-axis direction. In this embodiment, the first camera unit 151 is configured to capture the line tail from the negative direction of the Y-axis, but it may also be configured to capture the image from the positive direction of the Y-axis. The deviation of FAB301 easily occurs in the discharge direction, so the deviation can be accurately grasped based on the first image taken from the direction orthogonal to the discharge direction.

The second camera unit 152 is arranged to capture the line tail including the FAB 301 from the X-axis direction. The second camera unit 152 generates an image signal of a second image obtained by photographing the line end in the X-axis direction. In this embodiment, the second camera unit 152 is configured to capture the line tail from the negative direction of the X-axis, but it may also be configured to capture the line tail from the positive direction of the X-axis. If the second image is also used as a measurement object in addition to the first image, the offset of the FAB 301 can be accurately grasped from two orthogonal directions.

The imaging unit of this embodiment includes two imaging units, a first imaging unit 151 and a second imaging unit 152 , but further imaging units may be added. At this time, it is preferable that the additional imaging unit is installed in such a manner that the line tail can be photographed from a direction orthogonal to the Z-axis, which is the direction in which the line tail extends.

The measurement unit 171 measures the offset of the FAB 301 based on the acquired image. Here, the two measurement methods are explained using diagrams.

FIG. 4 is a diagram illustrating a first method of measuring the offset of FAB 301. The measuring unit 171 measures the first protrusion amount, which is the protrusion amount of the FAB 301 in one direction with respect to the central axis of the lead 300, and the second protrusion amount, which is the protrusion amount in another direction opposite to the one direction.

The left diagram of FIG. 4 shows the first image acquired from the first imaging unit 151. In the first image, the first protruding amount is from the surface of the lead 300 (the boundary line offset from the central axis of the lead 300 to the positive X-axis side by the radius of the lead 300 ) to the positive X-axis side of FAB 301 The distance D ₁ to the vertex. Similarly, the second protruding amount is from the surface of the lead 300 (a boundary line offset from the central axis of the lead 300 to the negative side of the X-axis by the radius of the lead 300 ) to the apex of the negative side of the X-axis of the FAB 301 The distance D ₂ . For example, if the eccentricity evaluation value = 1.0 - Min (D ₁ , D ₂ )/Max (D ₁ , D ₂ ), then a "-" sign is given when Max (D ₁ , D ₂ ) = D ₁ and when Max When (D ₁ , D ₂ )=D ₂ , a "+" sign is given to indicate which side and to what extent it is shifted. If D ₁ =D ₂ , the eccentricity evaluation value becomes 0, indicating that there is no deviation with respect to the shooting direction of the first image.

The right diagram of FIG. 4 shows the second image acquired from the second camera unit 152. In the second image, the first protruding amount is from the surface of the lead 300 (the boundary line offset from the central axis of the lead 300 to the negative side of the Y-axis by the radius of the lead 300 ) to the negative side of the Y-axis of FAB 301 The distance D ₃ to the vertex. Similarly, the second protruding amount is from the surface of the lead 300 (a boundary line offset from the central axis of the lead 300 to the positive Y-axis side by the radius of the lead 300 ) to the vertex of the FAB 301 on the positive Y-axis side. The distance D ₄ . Similarly, assuming that the eccentricity evaluation value = 1.0 - Min (D ₃ , D ₄ )/Max (D ₃ , D ₄ ), a "-" sign is given when Max (D ₃ , D ₄ ) = D ₃ . When Max (D ₃ , D ₄ )=D ₄ is given a "+" sign, it can indicate to which side and to what extent it is shifted. If D ₃ =D ₄ , the eccentricity evaluation value becomes 0, indicating that there is no deviation with respect to the shooting direction of the second image.

Furthermore, the diameter of the actual lead 300 inserted through the porcelain nozzle 133 is known, so the actual distance of each pixel can be calculated based on the width of the lead 300 on the image. In this way, the distance on the image (number of pixels) can be converted into the actual distance.

FIG. 5 is a diagram illustrating a second method of measuring the offset of FAB 301. The measuring unit 171 measures the amount of deviation of the center of the FAB 301 relative to the central axis of the lead wire 300 .

The left diagram of FIG. 5 shows the first image acquired from the first imaging unit 151. In the first image, the offset amount is the distance D _X from the central axis of FAB 301 to the center C _X of FAB 310 . For _{example ,} if the eccentricity evaluation value = _D +" symbol can indicate which side and to what extent it is offset. If _D

The right diagram of FIG. 5 shows the second image acquired from the second imaging unit 152 . In the second image, the offset amount is the distance D _Y from the central axis of FAB301 to the center C _Y of FAB310. For example, assuming that the eccentricity evaluation value = D _Y , a "-" sign is assigned when C _Y exists on the negative side of the Y-axis relative to the central axis, and a "-" sign is assigned when C _Y exists on the positive side of the Y-axis relative to the central axis. +" symbol can indicate which side and to what extent it is offset. If D _Y =0, the eccentricity evaluation value becomes 0, indicating that there is no deviation with respect to the shooting direction of the second image. Regarding the conversion from the distance on the image (number of pixels) to the actual distance, the situation is the same as in Figure 4.

The eccentricity measurement of the FAB 310 performed by the measurement unit 171 can be incorporated into various manufacturing steps that actually perform wiring operations. Here, three embodiments will be described using drawings.

FIG. 6 is a flowchart illustrating the processing procedure of the first embodiment including the eccentricity measurement of the FAB according to this embodiment. In the first embodiment, before performing the wiring operation, in order to determine the discharge conditions of the gas torch 131 in order to form a FAB that satisfies the reference, the eccentricity measurement of the FAB is performed. The process shown in the figure starts, for example, at a preparation time point before executing the connection operation.

In step S111 , the adjustment unit 172 receives an input of the initial settings regarding the discharge conditions of the torch 131 via the input/output device 190 . The adjustment unit 172 is not limited to using input from the input/output device 190 and may use predetermined initial settings. In step S112, the drive control unit 173 extends the lead wire 300 from the lead wire supply unit and extends the lead wire 300 from the front end of the porcelain nozzle 133 to form a wire tail. At this time, if the front end of the formed wire tail does not face the electrode of the gas torch 131, the tool driving motor 142 is driven in an opposite direction to adjust the height of the wire tail.

In step S113, the adjustment unit 172 applies a voltage to the electrode of the gas torch 131 according to the set discharge conditions to form the FAB 301 at the front end of the line tail. In step S114, the measurement unit 171 sends imaging request signals to the first imaging unit 151 and the second imaging unit 152 respectively to cause them to perform imaging processing, and obtain the first image and the second image obtained by photographing the end of the line including the FAB 301. . Then, in step S115 , the offset of the FAB 301 relative to the central axis of the lead 300 is measured based on the first image and the second image by using any of the measurement methods described in FIGS. 4 and 5 . Which measurement method to use can be selected by the operator in advance, or can be automatically selected according to the settings of the semiconductor chip 320 and the like. Alternatively, the control program can be made to correspond to only one measurement method.

In step S116, the measurement unit 171 determines whether the measurement result satisfies a preset standard. The standard is, for example, defined as an allowable amount of eccentricity evaluation value that does not cause a short circuit or other defect between the pad electrodes 321 . If the eccentricity evaluation value as the measurement result exceeds the allowable amount, the process proceeds to step S117. If it is within the allowable amount, it is considered that an appropriate FAB can be formed under the set and adjusted discharge conditions, and a series of preparation operations are completed, and the process waits until the wiring operation on the semiconductor chip 320 is performed.

When proceeding to step S117 , the arithmetic processing unit 170 connects the formed FAB 301 to a dummy electrode pad or the like, closes the wire clip 132 , and cuts the lead wire 300 . Next, in step S118, the adjustment unit 172 considers the measurement results obtained by the measurement unit 171 and adjusts the discharge conditions. That is, when the center is eccentric in a certain direction, the difference in cooling rate of the FAB surface is taken into account, and the spark current, current ramp time, gas flow rate, etc. are changed. When the eccentric direction is randomly changed, the spark is added taking into account the influence of vibration. Parameters that change the discharge conditions according to the magnitude or direction of the offset, such as the pre-delay time. After the adjustment of the discharge conditions is completed, in order to evaluate FAB 301 based on the adjusted discharge conditions, the process returns to step S112 and continues a series of processes.

If the wiring work of the semiconductor wafer 320 is started through such preparation work, the FAB can be stably formed from the initial stage of the wiring work.

7 is a flowchart illustrating the processing procedure of the second embodiment including the eccentricity measurement of the FAB according to this embodiment. In the second embodiment, the FAB actually formed during the execution of the connection job is monitored. The flow shown in the figure starts when the wiring operation is started for each semiconductor chip 320 provided on the substrate 330 of the platform 220 . In addition, the same process as that of each step explained using FIG. 6 is assigned the same step number, and the description thereof is omitted unless otherwise mentioned.

When the flow is started, steps S111 to S116 execute the same processing as the corresponding steps in FIG. 6 . However, the FAB 301 formed here is not formed for measurement, but is actually connected to the pad electrode 321 of the semiconductor wafer 320 .

After determining that the criterion is satisfied in step S116, the measurement unit 171 proceeds to step S121. The drive control unit 173 adheres the formed FAB 301 to the target pad electrode 321 and performs the first bonding. At this time, the arithmetic processing unit 170 sends an excitation signal and the like to the converter 134 and executes the control accompanying the first joining.

Next, in step S122, the drive control unit 173 moves the lead wire 300 to the corresponding lead electrode 322 to perform the second bonding. At this time, the arithmetic processing unit 170 sends an excitation signal and the like to the converter 134 and executes control accompanying the second joining. The arithmetic processing unit 170 proceeds to step S123, closes the wire clamp 132 and cuts the lead wire 300, and proceeds to step S124.

In step S124, the arithmetic processing unit 170 confirms whether all joining processes have been completed. If it is not completed, the process returns to step S112 to continue a series of processes in order to execute the remaining joining process. If it ends, a series of joining processes ends.

If the measurement unit 171 determines in step S116 that the standard is not satisfied, the process proceeds to step S125, and the drive control unit 173 does not cause the formed FAB 301 to adhere to the target pad electrode 321, but retreats to a predetermined position. Furthermore, the arithmetic processing unit 170 performs warning processing such as issuing a warning sound, informs the operator to interrupt the processing, and terminates the series of processing.

If this processing sequence is adopted, problems such as short circuits between the pad electrodes 321 can be prevented before they occur.

FIG. 8 is a flowchart illustrating the processing procedure of the third embodiment including the eccentricity measurement of the FAB according to this embodiment. In the third embodiment, the FAB actually formed during the execution of the wiring operation is monitored, and when the measurement results meet certain conditions, the wiring operation is continued while the discharge conditions are adjusted. The flow shown in the figure is the same as the flow shown in FIG. 7 , and starts at the time when the wiring operation is started for each semiconductor chip 320 placed on the substrate 330 of the platform 220 . Incidentally, the same steps as those described using FIGS. 6 and 7 are assigned the same step numbers, and description thereof will be omitted unless otherwise mentioned.

If the flow starts, steps S111 to S115 execute the same processing as the corresponding steps in FIG. 7 . If the process proceeds from step S115 to step S131, the measurement unit 171 determines whether the measurement result satisfies a preset first criterion. The first criterion is a criterion that determines that there is a high possibility of causing a malfunction such as a short circuit between the pad electrodes 321 when the first criterion is not satisfied. For example, the range is defined based on the eccentricity evaluation value. When the measurement result meets the first criterion, step S121 is entered to start the first bonding. When the measurement result does not meet the first criterion, the process proceeds to step S125, where backoff and warning processes are executed, and a series of processes are interrupted and ended.

When entering step S121, the process continues as described above until step S123. Next, after proceeding to step S132, the measurement unit 171 determines whether the measurement result measured in step S115 satisfies the second criterion. The second standard is a standard that can be evaluated as the optimal shape when the second standard is satisfied, and a range with less deviation than the first standard is set. In a situation where the second criterion is not satisfied but the first criterion is satisfied, even if the wiring operation is continued directly without causing a short circuit between the pad electrodes 321 or other malfunctions, the first criterion may not be satisfied due to some circumstances. Therefore, when the measurement unit 171 determines in step S132 that the second criterion is not satisfied, the process proceeds to step S133, and the adjustment unit 172 adjusts the discharge conditions considering the measurement results. That is, the parameters of the discharge conditions are changed according to the magnitude or direction of the offset. Then, proceed to step S124. When the measurement unit 171 determines in step S132 that the second criterion is satisfied, step S133 is skipped and the process proceeds to step S124.

If this processing sequence is adopted, problems such as short circuits between the pad electrodes 321 can be prevented before they occur, and the discharge conditions can be continuously adjusted, so that the wiring operation can be performed more optimally. Furthermore, by observing the condition of FAB301 formed continuously in this way, the change in offset can also be grasped. The adjustment unit 172 may also adjust the discharge conditions taking such changes into account. In addition, if a learned model generated based on the measured eccentricity evaluation value and the learning data of the offset of FAB 301 subsequently formed by the adjusted discharge conditions is prepared, the adjustment unit 172 may also use such a learned model. Adjust discharge conditions. In this case, the data obtained through actual online work can also be utilized as learning materials for re-learning.

In the wire bonding machine 100 described above, the imaging unit is composed of two imaging units, the first imaging unit 151 and the second imaging unit 152. However, from the viewpoint of simplifying the device, the imaging unit may be composed of one imaging unit. FIG. 9 is a perspective view schematically showing an essential part of a wire bonding machine 100' according to another embodiment. The same structures as those of the wire bonding machine 100 are denoted by the same symbols, and descriptions thereof are omitted.

The wire bonding machine 100' is different from the wire bonding machine 100 in the following aspects: the imaging unit is composed of one imaging unit 151'; and the imaging unit 151' is installed on the stand 210. When the imaging unit is constituted by one imaging unit, it is preferable to set it so that the line tail including FAB 301 is photographed from the direction orthogonal to the discharge direction as described above. The wire bonding machine 100' includes a camera unit 151' that captures the wire tail from the positive Y-axis direction, but may also include the camera unit 151' that captures the wire tail from the negative Y-axis direction.

In addition, if the imaging unit 151' is installed so as to be supported on the stand 210, it will not move with the movement of the head, so that the end of the line can be observed stably. However, the space where the line tail can be photographed is limited at this time, so the drive control unit 173 needs to drive the head 110 and the tool part 120 so that the line tail is located in the space. From this point of view, the structure in which the camera unit is supported on the stand 210 is better when implementing the first embodiment. Furthermore, multiple camera units can also be installed on the stand 210 to observe the line end from more than two directions.

The wire bonding machine 100 has been described above as an example of the wire bonding device. However, the bonding device to which the method or structure of measuring the offset of the FAB according to the present embodiment is applicable is not limited to wire bonding in which two bonding points are connected with a wire. Machine 100 example. For example, it is also applicable to a bump bonding machine that forms bumps on a plurality of electrodes on a substrate.

100, 100': wire bonding machine 110: head 120: tool part 131: gas torch 132: wire clamp 133: porcelain nozzle 134: converter 141: head drive motor 142: tool drive motor 151: first camera unit 151' :Camera unit 152: Second camera unit 170: Computational processing unit 171: Measurement unit 172: Adjustment unit 173: Drive control unit 180: Memory unit 190: Input and output device 210: Stand 220: Platform 300: Lead wire 301: FAB (none air ball) 320: _{semiconductor wafer} 321 _: pad _electrode 322 _: wire electrode ₃₃₀ : _{substrate C} ~S125, S131~S133: Steps

FIG. 1 is a perspective view schematically showing the main parts of a wire bonder according to this embodiment. Figure 2 is the system structure diagram of the wire bonding machine. FIG. 3 is a diagram explaining the observation status of FAB. FIG. 4 is a diagram illustrating a first method of measuring the offset of FAB. FIG. 5 is a diagram illustrating a second method of measuring the offset of FAB. FIG. 6 is a flowchart illustrating the processing procedure of the first embodiment including FAB measurement according to this embodiment. FIG. 7 is a flowchart illustrating the processing procedure of the second embodiment including FAB measurement of this embodiment. FIG. 8 is a flowchart illustrating the processing procedure of the third embodiment including FAB measurement according to this embodiment. FIG. 9 is a perspective view schematically showing an essential part of a wire bonding machine according to another embodiment.

100:Wire bonding machine

110:Head

120:Tool Department

131: Gas torch

132:Cable clip

133: porcelain mouth

134:Converter

141:Head drive motor

142:Tool drive motor

151: First camera unit

152: Second camera unit

210: Set up the platform

220:Platform

300:lead

301:FAB (airless balloon)

320:Semiconductor wafer

321: Pad electrode

322: Wire electrode

330:Substrate

Claims (7)

A wire bonding device, including: a porcelain nozzle, which supplies bonding wire; a gas torch, which forms an airless balloon at the end of the bonding wire extending from the porcelain nozzle; and a camera unit, which takes pictures at the front end through the gas torch The line tail is formed in a state where the airless balloon is formed; a measuring unit measures the offset of the airless balloon relative to the central axis of the bonding line based on the image output from the imaging unit; and The adjustment unit adjusts and changes parameters of the discharge conditions of the gas torch based on the measurement results obtained by the measurement unit. The wire bonding device according to claim 1, wherein the measuring part measures a first protrusion amount and a second protrusion amount, and the first protrusion amount is one direction of the airless balloon relative to the central axis of the bonding line. The second protrusion amount is the protrusion amount of the airless balloon in another direction opposite to the one direction relative to the central axis of the joint line. The wire bonding device according to claim 1 or claim 2, wherein the measuring part measures the offset amount of the center of the airless balloon relative to the central axis of the bonding wire. The wire bonding device according to claim 1 or claim 2, wherein the imaging unit is arranged to capture the wire tail from a direction that is consistent with a direction in which the wire tail extends from the porcelain nozzle. The extension direction is orthogonal to the discharge direction of the arc discharge generated between the gas torch and the line tail. The wire bonding device according to claim 1 or claim 2, wherein the imaging unit includes: a plurality of imaging units, from a plurality of directions orthogonal to the extension direction of the wire tail from the porcelain nozzle. Shoot the end of said line. A method for controlling a wire bonding device, including: a wire tail forming step, extending a bonding wire from the front end of a porcelain nozzle to form a wire tail; and an airless balloon forming step, using a gas torch to form an airless ball on the front end of the wire tail. balloon; a photographing step of photographing the line tail formed with the airless balloon; and a measuring step of measuring the deflection of the airless balloon relative to the central axis of the joint line based on the image output in the photographing step and an adjustment step, adjusting and changing parameters of the discharge conditions of the gas torch based on the measurement results obtained by the measurement step. A control program for a wire bonding device that causes a computer to execute: a wire tail forming step, extending the joining wire from the front end of the porcelain nozzle to form a wire tail; an airless balloon forming step, using an air torch to form a wire tail on the front end of the wire tail an airless balloon; a photographing step of photographing the line tail formed with the airless balloon; and a measuring step of measuring the central axis of the airless balloon relative to the joining line based on the image output in the photographing step offset; and an adjustment step of adjusting and changing parameters of the discharge conditions of the gas torch based on the measurement results obtained by the measurement step.

Images