KR20230174024A - Wire bonding apparatus and method for wire bondinof semiconducor package using the same - Google Patents

Abstract

In the wire bonding device and the wire bonding method of the semiconductor package using the same, the semiconductor package wire bonding method bonds the tip of the wire supplied through the wire clamp and the capillary to the bonding pad of the semiconductor chip on the package substrate, and the wire clamp With the false wire fixed, the capillary is moved to the connection pad of the package substrate corresponding to the bonding pad, the wire is bonded to the connection pad to form a wire connecting the bonding pad and the connection pad, and the wire clamp is attached to the wire. Release the fixation, and the encoder measures the height of the capillary based on the connection pad, and compares the measured height of the capillary with the height of the preset reference capillary to detect the degree of contamination of the portion where the wire is bonded to the connection pad. It includes doing.

Description

Wire bonding device and wire bonding method for semiconductor package using the same {WIRE BONDING APPARATUS AND METHOD FOR WIRE BONDINOF SEMICONDUCOR PACKAGE USING THE SAME}

The present invention relates to a wire bonding device including a wire clamp and a wire bonding method for a semiconductor package using the same.

Semiconductor packages are manufactured through several steps. For example, semiconductor packages are manufactured through a wire bonding process, a sawing process, a die bonding process, a molding process, and a marking process.

Here, the wire bonding process is a process of connecting the pads of a semiconductor chip and the leads of a lead frame with a wire, or connecting the pads of each semiconductor chip with a wire.

The wire material used is gold (Au), which has good conductivity, and the wire bonding device includes a capillary and a wire clamp. Here, the capillary may guide the wire by reciprocating between the pad of the semiconductor chip and the lead of the lead frame. Through this, the wire can electrically connect the pad of the semiconductor chip and the leads of the lead frame. The wire clamp can clamp or unclamp the wire to regulate the supply of the wire to the capillary.

However, if a wire break occurs due to a defective wire, the wire clamp clamps the broken wire. At this time, if the wire clamp does not quickly clamp the broken wire, the broken wire may escape outside the capillary.

The problem to be solved by the present invention is to measure the degree of contamination of the portion where the wire is bonded in the bonding pad of the semiconductor chip, and when contamination is detected, the wire clamp clamps the wire, thereby breaking the bonded wire due to contamination and causing capillary damage. The aim is to provide a wire bonding device that can prevent the wire from being released to the outside.

Another problem to be solved by the present invention is to provide a method for wire bonding a semiconductor package using the wire bonding device.

The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

One aspect of the bonding device according to the technical idea of the present invention for solving the above problem is a capillary that guides the wire, a wire clamp that controls the supply of the wire by fixing or unfixing the wire, The capillary is moved so that the wire is bonded to the bonding pad of the semiconductor chip on the package substrate, and when one side of the wire is bonded to the bonding pad, the capillary is moved so that the other side of the wire is bonded to the connection pad of the package substrate. A capillary transfer unit that transfers the filler, a drive motor that drives the capillary transfer unit, and a connection to the drive motor to measure the rotation angle of the drive motor, when the other side of the wire is bonded to the connection pad. , an encoder that measures the height of the capillary based on the connection pad, and a portion where the other side of the wire is bonded to the connection pad by comparing the measured height of the capillary with a preset reference capillary height. Includes a detection module that detects the level of contamination.

One aspect of the wire bonding method according to the technical idea of the present invention for solving the other problems is bonding the tip of a wire supplied through a wire clamp and a capillary to a bonding pad of a semiconductor chip on a package substrate, With the wire clamp fixing the wire, the capillary is moved to the connection pad of the package substrate corresponding to the bonding pad, and the wire is bonded to the connection pad to connect the bonding pad and the connection pad. forming a bonding wire, the wire clamp releases the fixation of the wire, the encoder measures the height of the capillary based on the connection pad, and the measured height of the capillary and the difference between the preset reference capillary It includes detecting the degree of contamination of the portion where the wire is bonded in the connection pad by comparing the height.

Other specific details of the invention are included in the detailed description and drawings.

1 is a schematic diagram showing a wire bonding device according to an embodiment according to the technical idea of the present invention.
Figure 2 is a cross-sectional view showing a semiconductor package including a wire manufactured by a wire bonding method for a semiconductor package according to an embodiment according to the technical idea of the present invention.
Figure 3 is a flowchart showing a wire bonding method for a semiconductor package according to an embodiment of the technical idea of the present invention.
FIG. 4 is a flowchart specifically illustrating the wire bonding method of the semiconductor package of FIG. 3.
5 to 16 are process diagrams showing the process sequence of a semiconductor package according to an embodiment of the technical idea of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings that can be commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless clearly specifically defined.

Hereinafter, with reference to the attached drawings, embodiments according to the technical idea of the present invention will be described.

1 is a schematic diagram showing a wire bonding device according to an embodiment according to the technical idea of the present invention.

Referring to FIG. 1, the wire bonding device 1 includes a capillary (CA), a transducer (not shown), a wire clamp (WC), a capillary transfer unit 2, a drive motor 4, It includes an encoder (EN), a detection module (6), and a control module (8).

The capillary (CA) may be equipped with a wire (10P, see FIG. 5) for a bonding process. The capillary CA supports the wire 10P, and a tip opening through which the wire 10P is discharged may be provided at its lower side.

The transducer may generate ultrasonic vibration so that the wire 10P is plastically deformed. The transducer can apply ultrasound through a capillary (CA).

The capillary transfer unit 2 may move the capillary CA and the wire clamp WC onto the bonding pad 115 of the semiconductor package to which the wire 10P is to be attached.

The wire clamp (WC) may support and guide the wire (1OP) so that the wire (10P) can be properly inserted into the capillary (CA). The wire clamp (WC) can apply tension to the wire. For example, the wire clamp (WC) can perform a close operation to fix or hold a wire and an open operation to unfix or release a wire by means of a piezoelectric element.

The drive motor 4 can drive the capillary transfer unit 2. The capillary transfer unit 2 moves the capillary (CA) in an upward and downward direction so that the capillary (CA) approaches or moves away from the bonding surface of the bonding pad 115 of the semiconductor chip 110 by the driving motor 4. It can be moved to .

The encoder (EN) can measure the height of the capillary (CA) in real time when wire bonding begins.

As will be described later, as shown in FIG. 8, while supporting the wire 10P, the capillary CA descends to the bonding surface of the bonding pad 115 and contacts the bonding pad 115, thereby causing the wire to contact the bonding pad. It can be bonded to the bonding surface of (115).

The capillary (CA) can rise when the wire (10P) is bonded to the bonding surface of the bonding pad (115).

The encoder (EN) may be connected to the drive motor (4) to measure the rotation angle of the drive motor (4). The encoder (EN) is a digital position sensor that measures rotation angle position and linear displacement, and can measure the height of the capillary (CA). That is, when the package substrate 210 is disposed along the X-axis direction, the encoder EN can measure the height of the capillary CA in the Z-axis direction.

Referring to FIG. 8, during the wire bonding process, one side of the wire 10P is bonded to the bonding pad 115 of the semiconductor chip 110 on the package substrate 210, and then the other side is bonded to the package substrate 210. It may be bonded to the connection pad 215 on the top. In this case, as described above, one side and the other side of the wire can be bonded to the bonding pad 115 and the connection pad 215, respectively, by moving the capillary CA while supporting the wire 10P. there is. The encoder EN can measure the height of the capillary CA based on the connection pad 215 when the other side of the wire 10P is bonded to the connection pad 215.

When contaminants are formed on the connection pad 215, the height of the capillary CA may be larger than when no contaminants are formed on the connection pad 215. The wire bonding device may preset the height of the capillary (CA) when no contaminants are formed on the connection pad 215 as the reference capillary height.

The detection module 6 compares the height of the capillary (CA) measured by the encoder (EN) with the set reference capillary height when the other side of the wire (10P) is bonded on the connection pad 215, The degree of contamination of the connection pad 215 where the other side of the wire is bonded can be detected.

That is, if the height of the capillary (CA) measured at the encoder (EN) is greater than the reference capillary height, the connection pad 215 is determined to be contaminated, and the capillary (CA) measured at the encoder (EN) is determined to be contaminated. ) If the height is the same as the reference capillary height, it can be determined that the connection pad 215 is not contaminated.

The detection module 6 may generate a wire disconnection prediction signal when the measured height of the capillary (CA) is greater than the reference capillary height. Furthermore, when the measured height of the capillary (CA) is greater than the difference between the reference capillary height and the set value, a wire disconnection prediction signal may be generated.

The control module 8 is electrically connected to the detection module 6, and can control the wire clamp WC so that the wire clamp WC fixes the wire 1OP according to the wire breakage prediction signal.

Hereinafter, a semiconductor package manufactured by the wire bonding method of a semiconductor package using the wire bonding device of FIG. 1 described above will be described.

Figure 2 is a cross-sectional view showing a semiconductor package including a wire manufactured by a wire bonding method for a semiconductor package according to an embodiment according to the technical idea of the present invention.

Referring to FIG. 2, the semiconductor package 100 includes a semiconductor chip 110, a package substrate 210, a molding member 310, and a bonding wire 10 formed by a wire bonding method according to the technical idea of the present invention. can do.

The semiconductor package 100 may include a semiconductor chip 110 mounted in a vertical direction on the package substrate 210 . The semiconductor chip 110 may be electrically connected to the package substrate 210 through a bonding wire 10. Although the semiconductor package 100 in which one semiconductor chip 110 is mounted is shown as an example, the number of semiconductor chips mounted in the semiconductor package 100 is not limited thereto.

For example, a plurality of semiconductor chips 110 may be mounted within the semiconductor package 100. Additionally, the semiconductor chip 110 may be a memory chip and/or a logic chip. For example, when a plurality of semiconductor chips 110 are mounted, all of the semiconductor chips 110 may be the same type of memory chip, or some of the semiconductor chips 110 may be memory chips and others may be logic chips. . The memory chips may be volatile or non-volatile memory chips.

Volatile memory chips may be implemented as, for example, dynamic random access memory (DRAM), static RAM (SRAM), or thyristor RAM (TRAM), but are not limited thereto.

In addition, non-volatile memory chips include, for example, flash memory, magnetic RAM (MRAM), spin-transfer torque MRAM (STT-MRAM), ferroelectric RAM (FRAM), phase change RAM (PRAM), and resistive RAM (RRAM). RAM), etc., but is not limited to this.

A logic chip may be implemented as, for example, a microprocessor, graphics processor, signal processor, network processor, chipset, audio codec, video codec, application processor, system on chip, etc., but is not limited to these. no.

The semiconductor chip 110 may include a semiconductor substrate 113 and a bonding pad 115. The semiconductor substrate 113 may have upper and lower surfaces facing each other. The semiconductor substrate 113 may include a semiconductor device (not shown).

Bonding pad 115 may be formed on the semiconductor device. The material constituting the bonding pad 115 may include at least one of aluminum (Al), copper (Cu), nickel (Ni), tungsten (W), platinum (Pt), and gold (Au). It is not limited to this.

The semiconductor substrate 113 may include, for example, silicon. Alternatively, the semiconductor substrate 113 may include a semiconductor element such as germanium, or a compound semiconductor such as silicon carbide (SiC), gallium arsenide (GaAs), indium arsenide (InAs), or indium phosphide (InP). . Alternatively, the semiconductor substrate 113 may have a silicon on insulator (SOI) structure. For example, the semiconductor substrate 113 may include a BOX layer (buried oxide layer). The semiconductor substrate 113 may include a conductive region, for example, a well doped with an impurity or a structure doped with an impurity. The semiconductor substrate 113 may have various device isolation structures, such as a shallow trench isolation (STI) structure.

A passivation layer (not shown) may be formed on the semiconductor substrate 113 to protect the semiconductor devices and other structures within the semiconductor substrate 113 from external shock or moisture. The passivation layer may expose at least a portion of the upper surface of the bonding pad 115.

An adhesive film (AF) is disposed between the upper surface of the package substrate 210 and the lower surface of the semiconductor chip 110 to attach the semiconductor chip 110 to the package substrate 210. The adhesive film (AF) may be, for example, a die attach film (DAF). Die attach films can be divided into inorganic adhesives and polymer adhesives, and there is also a hybrid type made by mixing these two ingredients.

The package substrate 210 is a support substrate and a mounting substrate and may include a body portion 213 and a protective layer. The package substrate 210 may be formed based on a printed circuit board (PCB), a wafer substrate, a ceramic substrate, a glass substrate, and an interposer. The package substrate 210 may be a printed circuit board. Of course, the package substrate 210 is not limited to a printed circuit board.

Internal wiring (not shown) may be formed on the package substrate 210, and the internal wiring is connected to the semiconductor chip 110 through a bonding wire 10 connected to the connection pad 215 on the top surface of the package substrate 210. Can be electrically connected.

When the package substrate 210 is a printed circuit board, the body portion 213 is typically made of polymer materials such as thermosetting resin, Flame Retardant 4 (FR-4), Bismaleimide Triazine (BT), and Ajinomoto Build up Film (ABF). It can be implemented by compressing an epoxy resin such as an epoxy resin or a phenolic resin to a certain thickness to form a thin shape, coating both sides with copper foil, and then forming an internal wiring, which is a transmission path for electrical signals, through patterning. .

Meanwhile, a printed circuit board can be divided into a single-layer PCB (single layer PCB) with internal wiring formed on only one side, and a double-layer PCB (double layer PCB) with internal wiring formed on both sides. In addition, three or more layers of copper foil can be formed using an insulator called prepreg, and a PCB with a multi-layer structure can be implemented by forming three or more internal wirings depending on the number of layers of copper foil formed. . Of course, the package substrate 210 is not limited to the structure or material of the printed circuit board described above.

The molding member 310 may be formed on the package substrate 210 to surround the semiconductor chip 110 and the bonding wire 10. The molding member 310 may be formed of, for example, epoxy molding compound.

In contrast, the molding member 310 is not limited to epoxy molding compound and may be formed of various materials, such as epoxy-based materials, thermosetting materials, thermoplastic materials, UV-treated materials, etc. In the case of thermosetting materials, phenol-type, acid anhydride-type, and amine-type curing agents and acrylic polymer additives may be included.

The molding member 310 injects an appropriate amount of molding material onto the package substrate 210 through an injection process, and forms the outer shape of the semiconductor package 100 through a curing process. If necessary, pressure is applied to the molding material in a pressurizing process such as a press to form the outer shape of the semiconductor package 100. Here, process conditions such as delay time between molding material injection and pressurization, amount of molding material injected, and pressurizing temperature/pressure can be set in consideration of physical properties such as viscosity of the molding material. The side and top surfaces of the molding member 310 may have a right-angled shape.

Although not shown, a marking pattern including information on the semiconductor chip 110, for example, a barcode, QR code, number, letter, or symbol, may be formed on the side and/or top surface of the molding member 310.

The molding member 310 may serve to protect the semiconductor chip 110 and the bonding wire 10 from external influences such as contamination and impact. In order to perform this role, the thickness of the molding member 310 may be formed to at least enclose both the semiconductor chip 110 and the bonding wire 10. Since the molding member 310 completely covers the package substrate 210, the width of the molding member 310 may be substantially the same as the width of the semiconductor package 100.

The bonding wire 10 formed by the wire bonding method according to the technical idea of the present invention may be formed to electrically connect the bonding pad 115 and the connection pad 215. At least one of a control signal, a power signal, and a ground signal for operation of the semiconductor chip 110 may be provided from the outside through the bonding wire 10. Additionally, data signals to be stored in the semiconductor chip 110 may be provided from the outside through the bonding wire 10, or data stored in the semiconductor chip 110 may be provided to the outside.

Although the bonding wire 10 is shown as an example disposed only on one side of the semiconductor chip 110, the arrangement of the bonding wire 10 is not limited to this. For example, bonding wires 10 may be disposed on two or more sides of the semiconductor chip 110. The material constituting the bonding wire 10 may include at least one of gold (Au), silver (Ag), copper (Cu), and aluminum (Al).

The bonding wire 10 may be connected by either a thermo compression connection or an ultrasonic connection, or a thermo sonic connection that combines the thermo compression connection and the ultrasonic connection method. It can also be connected by method.

Bonding wire 10 may include a ball portion 11, a neck portion 13, a wire portion 15, and a stitch portion 17. Specifically, the ball portion 11 may be positioned to directly contact the upper surface of the bonding pad 115. The neck portion 13 may be located on the upper surface of the cheek portion 11. The stitch portion 17 may be positioned to directly contact the upper surface of the connection pad 215. The wire portion 15 may connect the neck portion 13 and the stitch portion 17. That is, the bonding pad 115 and the bonding wire 10 may be bonded using a ball bonding method, and the connection pad 215 and the bonding wire 10 may be bonded using a stitch bonding method.

As the degree of integration of the semiconductor chip 110 required in recent electronic devices gradually increases, the number of bonding wires 10 included in the semiconductor package 100 is increasing. Accordingly, a fast work speed of bonding equipment for forming the bonding wire 10 is required.

Accordingly, the wire bonding method according to the technical idea of the present invention, which will be described later, improves the operation rate of the bonding facility by solving the temporary stoppage of the bonding facility due to contamination of the portion where the wire 10P is bonded in the connection pad 215. As a result, it is possible to ultimately increase the manufacturing efficiency of the semiconductor package 100 and improve productivity and economic efficiency.

Figure 3 is a flowchart showing a wire bonding method for a semiconductor package according to an embodiment of the technical idea of the present invention.

The wire bonding method of a semiconductor package according to the technical idea of the present invention may include the following process sequence. In cases where an embodiment can be implemented differently, a specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially at the same time, or may be performed in an order opposite to the order in which they are described.

Referring to FIG. 3, a first step of forming a first bond on a bonding pad (S110), a second step of forming a wire loop (S120), a third step of forming a second bond on a connection pad (S140), The fourth step (S450) of detecting the degree of contamination of the portion where the wire is bonded in the connection pad 215, the fifth step (S560) of forming a free air ball at the tip of the wire (10P), and the separation of the wire (10P). A wire bonding method (S10) including a sixth step (S160) of prevention is shown.

In the wire bonding method (S10) according to the technical idea of the present invention, according to the detection result of the fourth step (S140) of detecting the degree of contamination of the wire, it is determined that the portion where the wire is bonded in the connection pad 215 is not contaminated. If this happens (i.e., no defect occurs), the process proceeds to the fifth step (S150) of forming a free air ball at the tip of the wire 10P, and one cycle of the wire forming process is normally completed.

If the portion where the wire 10P is bonded to the connection pad 215 is determined to be contaminated (i.e., a defect occurs), the process proceeds to the sixth step (S160) to prevent the wire 10P from being separated. , and then proceeds to the fifth step (S150) of forming a free air ball at the tip of the wire, and one cycle of the wire forming process is normally completed.

That is, the wire bonding method (S10) according to the technical idea of the present invention is to determine whether the wire is contaminated in order to solve the temporary stoppage of the bonding facility due to contamination of the portion where the wire 10P is bonded in the connection pad 215. By designing each step to detect , it is possible to increase the manufacturing efficiency of semiconductor packages and improve productivity and economic efficiency.

FIG. 4 is a flowchart specifically showing the wire bonding method of the semiconductor package of FIG. 3, and FIGS. 5 to 18 are process charts showing the process sequence of the semiconductor package according to an embodiment of the technical idea of the present invention.

Referring to FIG. 4, the wire bonding method (S20) according to the technical idea of the present invention specifically includes a step of detecting contamination of the portion where the wire is bonded to the connection pad before the capillary rises from the connection pad. It is explained as: If the part of the connection pad where the wire is bonded is contaminated (i.e., a defect occurs), the wire clamp can be changed to a closed state to prevent the wire from leaving the capillary.

Therefore, if the wire forming process is performed using the wire bonding method (S20), continuous processing is possible without temporary stoppage of the bonding equipment even if a defect occurs during the process, thereby dramatically increasing the operation rate of the bonding equipment. Accordingly, the manufacturing efficiency of semiconductor packages can be increased, and productivity and economic efficiency can be improved.

Referring to FIG. 5 , the semiconductor chip 110 may include a bonding pad 115 and the package substrate 210 may include a connection pad 215 . The semiconductor chip 110 may be mounted on the package substrate 210 so that the connection pad 215 is not obscured. An adhesive film (AF) is interposed between the upper surface of the package substrate 210 and the lower surface of the semiconductor chip 110, so that the semiconductor chip 110 can be attached to the package substrate 210.

The capillary CA may be disposed on the top of the bonding pad 115 and spaced apart by a certain distance. A portion of the wire 10P may protrude from the center hole of the capillary CA.

The material constituting the wire 10P may include at least one of silver, gold (Au), silver (Ag), copper (Cu), and aluminum (Al). An electric spark may be provided to the wire 10P protruding from the center hole of the capillary CA, so that the lower end of the wire 10P may be melted. Accordingly, a free air ball (10F) may be formed at the lower end of the wire (10P) in the center hole of the capillary (CA).

Instead of electric sparks, ultrasonic energy or thermal energy may be provided to the bottom of the wire 10P. The movement of the wire 10P within the capillary CA may be restricted by the closing operation of the wire clamp WC.

Referring to FIGS. 4 and 6 , the capillary CA moves toward the bonding pad 115 so that the free air ball 10F (see FIG. 5 ) may contact the bonding pad 115 . Accordingly, the tip of the wire 10P supplied through the wire clamp WC and the capillary CA can be bonded to the bonding pad 115 of the semiconductor chip 110 on the package substrate 210 (step S210).

In this case, the free air ball (10F, see FIG. 4) is compressed between the capillary (CA) and the bonding pad 115, forming the ball portion 11 and the neck portion 13 at the bottom of the wire 10P. can be formed. Thermal energy and/or ultrasonic energy may be provided to the semiconductor chip 110 so that the ball portion 11 can be bonded to the bonding pad 115 . Bonding using a ball bonding method in which the ball portion 11 is bonded to the bonding pad 115 may be implemented. The neck portion 13 may be formed in a shape according to the chamfer angle inside the capillary (CA). The diameter of the neck portion 13 may be formed to be smaller than the diameter of the ball portion 11, and accordingly, the neck portion 13 may be arranged to be completely seated on the upper surface of the ball portion 11.

Referring to FIG. 7, the capillary (CA) moves upward in the vertical direction from the upper surface of the bonding pad 115, exposing the neck portion 13 and the wire 10P to the outside of the capillary (CA). You can. The capillary CA may rise vertically to be positioned at a height corresponding to a predetermined distance from the bonding pad 115. The wire 10P may form a wire portion 15 extending vertically from the upper surface of the neck portion 13 by the open state of the wire clamp WC.

Referring to FIGS. 4 and 8 , with the wire clamp (WC) fixing the wire (10P), the capillary (CA) is connected to the connection pad 215 of the package substrate 210 corresponding to the bonding pad 115. can be moved (step S220). That is, the capillary CA moved upward in the vertical direction from the bonding pad 115 may slide toward the connection pad 215. As the capillary (CA) slides while the wire clamp (WC) is open, the wire portion 15 discharged from the lower end of the capillary (CA) may extend along the sliding of the capillary (CA). .

Through this, the wire portion 15 can be formed between the bonding pad 115 and the connection pad 215. The wire portion 15 forms a wire loop, and the wire portion 15 can move along the curvature trajectory of the capillary CA without being broken. That is, by bonding the wire 10P to the connection pad 215, the bonding wire 10 connecting the bonding pad 115 and the connection pad 215 is formed (step S230).

When the bonding wire 10 is formed, the wire clamp WC can release the fixation of the wire 10P as shown in FIG. 9 (step S240).

Before the capillary (CA) moves upward on the connection pad 215, the height of the capillary (CA) can be measured by measuring the rotation angle of the driving motor at the encoder (EN) (step S250). In other words, the encoder EN can measure the height of the capillary CA that guides the wire 10P when the wire 10P is bonded to the connection pad 215 (step S250).

When the portion of the connection pad 215 where the wire 10P is bonded is contaminated, contaminants are formed on the connection pad 215, so the capillary CA is more sensitive than when the connection pad 215 is not contaminated. It is located in a high position. Accordingly, if the height of the capillary (CA) measured by the encoder (EN) is higher than the height of the reference capillary, the detection module described above determines that contaminants have formed in the portion where the wire is bonded in the connection pad 215. This can be done, and if the height of the capillary (CA) measured by the encoder (EN) is the same as the reference capillary height, it can be determined that no contaminants are formed in the area where the wire is bonded in the connection pad 215. There is (step S260).

Referring to FIG. 9, when it is confirmed that the portion of the connection pad 215 to which the wire 10P is bonded is not contaminated, the wire clamp WC releases the wire 10P and clamps the capillary. Li (CA) may move upward in the vertical direction from the upper surface of the connection pad 215. With the wire 10P in contact with the contact point CP of the connection pad 215, the wire 10P may be extended. That is, if no defect occurs, the wire 10P may protrude to the outside of the capillary CA and be electrically connected to the connection pad 215.

Referring to FIG. 10, as the capillary (CA) continues to move upward while the wire clamp (WC) is open, the wire (10P) is completely cut off from the stitch portion (17), and through this, the bonding pad (115) ) can be formed to form a bonding wire 10 that electrically connects the connection pad 215. Stitch bonding may be implemented in which the stitch portion 17, which is part of the bonding wire 10, is adhered to the connection pad 215.

When the wire 10P is separated from the stitch portion 17 and/or the connection pad 215, thermal energy or ultrasonic energy may be applied to the wire 10P. The capillary (CA) can be raised to a level corresponding to the electronic flame-off height, and a new free air ball (10F, see FIG. 15) is formed at the bottom of the wire (10P) through the process of FIG. 15 described later. It can be. That is, one cycle of the wire forming process ends normally, and the capillary (CA) can proceed with a new cycle of the wire bonding process or wait.

Referring to FIG. 11, before the capillary (CA) rises from the connection pad 215, if it is confirmed that the portion where the wire 10P is bonded on the connection pad 215 is in a contaminated state (i.e., defective) When this occurs), the wire clamp (WC) can be changed to a closed state to prevent the wire (10P) from leaving the capillary (CA).

If the measured height of the capillary (CA) is greater than the reference capillary height, or the difference between the measured height of the capillary (CA) and the reference capillary height is greater than a preset value, the detection module (6 ), a wire disconnection prediction signal is generated, and the control module 8 can control the wire clamp (WC) so that the wire clamp (WC) fixes the wire (10P) according to the wire disconnection prediction signal.

Accordingly, the wire clamp WC is changed to the closed state, so that the tip 19 of the wire 10P can remain inside the capillary CA. This is because, if the wire clamp (WC) is maintained in the open state, as the wire (10P) is contaminated and a break occurs in the bonded portion to the connection pad 215, the wire (10P) is not fixed, and the wire (10P) is not fixed. This is because the wire 10P may be separated from the capillary CA as the wire 10P is wound up by the tension of the reel.

12 and 13, when the wire clamp (WC) is closed, the capillary (CA) moves vertically upward from the upper surface of the connection pad 215, so that a portion of the wire 10P is connected to the connection pad. It is separated from (215). As a result, the bonding wire 10 that electrically connects the bonding pad 115 and the connection pad 215 can be formed. Stitch bonding may be implemented in which the stitch portion 17, which is part of the bonding wire 10, is adhered to the connection pad 215.

However, unlike shown in FIG. 8, the tip 19 of the wire 10P does not protrude from the capillary CA but is located inside the capillary CA, and the tip 19 of the wire 10P A free air ball cannot be formed in

Referring to FIG. 1, the wire clamp (WC) is changed to the open state, and the capillary (CA) is vibrated up and down so that the tip 19 of the wire (10P) protrudes to the outside of the capillary (CA). Due to the vertical vibration of the capillary (CA) using the vibration device (VB), the tip 19 of the wire (10P) protrudes out of the capillary (CA) in the direction in which the connection pad 215 is located. You can move downward. The process of vibrating the capillary (CA) up and down can be done by adding ultrasonic vibration to the capillary (CA). However, the ultrasonic vibration may not be performed as needed.

Referring to Figures 15 and 16, a new free air ball (10F) can be formed at the bottom of the wire (10P). An electric spark may be provided to the lower end of the wire 10P protruding from the center hole of the capillary CA using the discharge electrode BT, so that the lower end of the wire 10P may be melted. Accordingly, a new free air ball 10F may be formed at the lower end of the wire 10P in the center hole of the capillary CA. Instead of electric sparks, ultrasonic energy or thermal energy may be provided to the bottom of the wire 10P. That is, one cycle of the wire forming process ends normally, and the capillary (CA) can proceed with a new cycle of the wire bonding process or wait.

The wire 10P on which the free air ball 10F is formed can be moved onto a new bonding pad (not shown) of the semiconductor chip 110. A state may be provided in which a wire (not shown) that electrically connects the bonding pad and a new connection pad (not shown) of the package substrate 210 can be continuously formed.

Although embodiments according to the technical idea of the present invention have been described with reference to the attached drawings, the present invention is not limited to the above embodiments and can be manufactured in various different forms, and is commonly known in the technical field to which the present invention pertains. Those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

1: Wire bonding device 2: Capillary transfer unit
4: Drive motor 6: Detection module
8: Control module CA: Capillary
WC: Wire clamp EN: Encoder

Claims (11)

A capillary that guides the wire;
a wire clamp that controls supply of the wire by fixing or unfixing the wire;
The capillary is moved so that the wire is bonded to the bonding pad of the semiconductor chip on the package substrate, and when one side of the wire is bonded to the bonding pad, the other side of the wire is bonded to the connection pad of the package substrate. A capillary transfer unit that transfers the capillary;
A driving motor that drives the capillary transfer unit;
an encoder connected to the drive motor to measure the rotation angle of the drive motor and measuring the height of the capillary based on the connection pad when the other side of the wire is bonded to the connection pad; and
A wire bonding device comprising a detection module that detects a degree of contamination of a portion of the connection pad where the other side of the wire is bonded by comparing the measured height of the capillary with a preset reference capillary height. According to clause 1,
The package substrate is disposed along the X-axis direction,
The encoder is a wire bonding device that measures the height of the capillary in the Z-axis direction. According to clause 1,
The detection module is,
When the measured height of the capillary is greater than the reference capillary height,
A wire bonding device that generates a wire break prediction signal. According to clause 1,
The detection module is,
A wire bonding device that generates a wire disconnection prediction signal when the difference between the measured height of the capillary and the reference capillary height is greater than a preset value. According to claim 3 or 4,
A wire bonding device that is electrically connected to the detection module and further includes a control module that controls the wire clamp to fix the wire according to the wire disconnection prediction signal. Bonding the tip of the wire supplied through the wire clamp and capillary to the bonding pad of the semiconductor chip on the package substrate,
With the wire clamp fixing the wire, the capillary is moved to a connection pad of the package substrate corresponding to the bonding pad,
Bonding the wire to the connection pad to form a bonding wire connecting the bonding pad and the connection pad,
the wire clamp releases the fixation of the wire,
An encoder measures the height of the capillary based on the connection pad, and
A wire bonding method comprising detecting a degree of contamination of a portion of the connection pad to which the wire is bonded by comparing the measured height of the capillary with a preset height of a reference capillary. According to clause 6,
Detecting the level of contamination is,
When the measured height of the capillary is greater than the reference capillary height,
A wire bonding method comprising generating a wire breakage prediction signal. According to clause 6,
Detecting the level of contamination is,
A wire bonding method comprising generating a wire disconnection prediction signal when the difference between the measured height of the capillary and the reference capillary height is greater than a preset value. According to claim 7 or 8,
A wire bonding method further comprising controlling the wire clamp so that the wire clamp fixes the wire according to the wire disconnection prediction signal. According to clause 9,
If the wire breaks while the wire clamp is holding the wire,
A wire bonding method further comprising raising the capillary. According to clause 8,
Detecting the level of contamination is,
When the difference between the measured height of the capillary and the reference capillary height is less than a preset value,
maintaining the wire clamp in a released state of the wire and raising the capillary from the connection pad;
A wire bonding method further comprising raising the capillary further after allowing the wire clamp to secure the wire.

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