Wire bonding apparatus and method for wire bondinof semiconducor package using the same

Abstract

In a wire bonding device and a wire bonding method for a semiconductor package using the same, the semiconductor package wire bonding method comprises bonding the leading end of a wire supplied through a wire clamp and a capillary to a bonding pad of a semiconductor chip on a package substrate, moving the capillary to a connection pad of the package substrate corresponding to the bonding pad while the wire clamp is fixed, bonding the wire to the connection pad to form a wire connecting the bonding pad and the connection pad, releasing the wire clamp from fixing the wire, measuring the height of the capillary with respect to the connection pad with respect to an encoder, and detecting the degree of contamination of the portion where the wire is bonded at the connection pad by comparing the measured height of the capillary with a preset reference height of the capillary.

Description

Technology Field

[0001] 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. Background Technology

[0002] Semiconductor packages are manufactured through multiple process stages. For example, semiconductor packages are manufactured through processes such as wire bonding, sawing, die bonding, molding, and marking.

[0003] Here, the wire bonding process is a process of connecting the pads of a semiconductor chip to the leads of a lead frame with a wire, or connecting the pads of each semiconductor chip with a wire.

[0004] The wire material used is gold (Au) or similar, which has good conductivity, and the wire bonding device includes a capillary and a wire clamp. Here, the capillary can guide the wire by reciprocating between the pads of the semiconductor chip and the leads of the lead frame. Through this, the wire can electrically connect the pads of the semiconductor chip and the leads of the lead frame. The wire clamp can control the supply of the wire to the capillary by clamping or releasing the wire. The problem to be solved

[0005] However, if a wire break occurs due to a defect, the wire clamp will clamp the broken wire. At this time, if the wire clamp fails to clamp the broken wire quickly, the broken wire may detach from the capillary.

[0006] The problem that the present invention aims to solve is to provide a wire bonding device capable of measuring the degree of contamination of a portion where a wire is bonded at a bonding pad of a semiconductor chip, and, when contamination is detected, clamping the wire with a wire clamp to prevent the bonded wire from breaking and detaching from the capillary due to contamination.

[0007] Another problem that the present invention aims to solve is to provide a wire bonding method for a semiconductor package using the wire bonding device described above.

[0008] The problems that the present invention aims to solve are not limited to the technical problems mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0009] One aspect of a bonding device according to the technical concept of the present invention for solving the above problem comprises: a capillary for guiding a wire; a wire clamp for controlling the supply of the wire by fixing or releasing the wire; a capillary transfer unit for moving the capillary so that the wire is bonded to a bonding pad of a semiconductor chip on a package substrate, and transferring the capillary so that when one side of the wire is bonded to the bonding pad, the other side of the wire is bonded to a connection pad of the package substrate; a driving motor for driving the capillary transfer unit; an encoder connected to the driving motor to measure the rotation angle of the driving motor, and measuring the height of the capillary relative to the connection pad when the other side of the wire is bonded to the connection pad; and a detection module for detecting the degree of contamination of the 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 height of the capillary.

[0010] One aspect of the wire bonding method according to the technical concept of the present invention for solving the above other problems comprises bonding the leading end of a wire supplied through a wire clamp and a capillary to a bonding pad of a semiconductor chip on a package substrate, moving the capillary to a connection pad of the package substrate corresponding to the bonding pad while the wire clamp is fixed, bonding the wire to the connection pad to form a bonding wire connecting the bonding pad and the connection pad, releasing the wire clamp from fixing the wire, and an encoder measuring the height of the capillary relative to the connection pad, and detecting the degree of contamination of the portion where the wire is bonded at the connection pad by comparing the measured height of the capillary with a preset reference height of the capillary.

[0011] Other specific details of the present invention are included in the detailed description and drawings. Brief explanation of the drawing

[0012] FIG. 1 is a schematic diagram showing a wire bonding device according to one embodiment according to the technical concept of the present invention. FIG. 2 is a cross-sectional view showing a semiconductor package including a wire manufactured by a wire bonding method of a semiconductor package according to one embodiment of the technical concept of the present invention. FIG. 3 is a flowchart illustrating a wire bonding method for a semiconductor package according to one embodiment of the technical concept of the present invention. Figure 4 is a flowchart specifically illustrating the wire bonding method of the semiconductor package of Figure 3. FIGS. 5 to 16 are process diagrams showing the process sequence of a semiconductor package according to one embodiment of the technical concept of the present invention. Specific details for implementing the invention

[0013] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning that is commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0014] Embodiments according to the technical concept of the present invention will be described below with reference to the attached drawings.

[0015] FIG. 1 is a schematic diagram showing a wire bonding device according to one embodiment according to the technical concept of the present invention.

[0016] 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), an encoder (EN), a detection module (6), and a control module (8).

[0017] A wire (10P, see FIG. 5) for a bonding process may be mounted on the capillary (CA). The capillary (CA) supports the wire (10P), and a tip opening may be provided on the lower side through which the wire (10P) is discharged.

[0018] The transducer can generate ultrasonic vibrations to cause the wire (10P) to undergo plastic deformation. The transducer can apply ultrasonic waves to the capillary (CA).

[0019] The capillary transfer unit (2) can move the capillary (CA) and wire clamp (WC) onto the bonding pad (115) of the semiconductor package to which the wire (10P) is to be attached.

[0020] The wire clamp (WC) can 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 the wire by means of a piezoelectric element, and an open operation to release or unlock the wire.

[0021] The drive motor (4) can drive the capillary transfer unit (2). The capillary transfer unit (2) can move the capillary (CA) in an up-and-down direction by the drive motor (4) so ​​that the capillary (CA) moves closer to or further away from the bonding surface of the bonding pad (115) of the semiconductor chip (110).

[0022] The encoder (EN) can measure the height of the capillary (CA) in real time when wire bonding begins.

[0023] As will be described later, as illustrated in FIG. 8, the capillary (CA) can be lowered to the bonding surface of the bonding pad (115) while supporting the wire (10P) and come into contact with the bonding pad (115) so that the wire is bonded to the bonding surface of the bonding pad (115).

[0024] The capillary (CA) can be raised when the wire (10P) is bonded to the bonding surface of the bonding pad (115).

[0025] An encoder (EN) can 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 the rotation angle position and linear displacement, and can measure the height of the capillary (CA). That is, when the package substrate (210) is positioned along the X-axis direction, the encoder (EN) can measure the height of the capillary (CA) in the Z-axis direction.

[0026] Referring to FIG. 8, during the wire bonding process, one side of the wire (10P) may be bonded to a bonding pad (115) of a semiconductor chip (110) on a package substrate (210), and then the other side may be bonded to a connection pad (215) on the package substrate (210). In this case, as described above, the 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 while the capillary (CA) supports the wire (10P). The encoder (EN) can measure the height of the capillary (CA) relative to the connection pad (215) when the other side of the wire (10P) is bonded to the connection pad (215).

[0027] When contaminants are formed on the connection pad (215), the height of the capillary (CA) may be formed to be greater than when contaminants are not formed on the connection pad (215). The wire bonding device may pre-set the height of the capillary (CA) in the case where contaminants are not formed on the connection pad (215) as the reference capillary height.

[0028] The detection module (6) can detect the degree of contamination of the part where the other side of the wire is bonded to the connection pad (215) by comparing 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 to the connection pad (215).

[0029] That is, if the height of the capillary (CA) measured by the encoder (EN) is greater than the reference capillary height, it is determined that the connection pad (215) is contaminated, and if the height of the capillary (CA) measured by the encoder (EN) is equal to the reference capillary height, it is determined that the connection pad (215) is not contaminated.

[0030] The detection module (6) can generate a wire breakage prediction signal when the height of the measured capillary (CA) is greater than the reference capillary height. Furthermore, when the difference between the height of the measured capillary (CA) and the reference capillary height is greater than a set value, the wire breakage prediction signal can be generated.

[0031] 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.

[0032] Below, a semiconductor package manufactured using the wire bonding method of a semiconductor package using the wire bonding device of Fig. 1 described above will be explained.

[0033] FIG. 2 is a cross-sectional view showing a semiconductor package including a wire manufactured by a wire bonding method of a semiconductor package according to one embodiment of the technical concept of the present invention.

[0034] Referring to FIG. 2, the semiconductor package (100) may include 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 concept of the present invention.

[0035] A semiconductor package (100) may include a semiconductor chip (110) mounted vertically on a package substrate (210). The semiconductor chip (110) may be electrically connected to the package substrate (210) through a bonding wire (10). Although a semiconductor package (100) with one semiconductor chip (110) mounted thereon is illustrated as an example, the number of semiconductor chips mounted within the semiconductor package (100) is not limited thereto.

[0036] For example, multiple semiconductor chips (110) may be mounted within a semiconductor package (100). Additionally, the semiconductor chips (110) may be memory chips and / or logic chips. For example, when multiple semiconductor chips (110) are mounted, the semiconductor chips (110) may all be of the same type of memory chips, 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.

[0037] Volatile memory chips can be implemented as, for example, DRAM (dynamic random access memory), SRAM (static RAM), TRAM (thyristor RAM), etc., but are not limited thereto.

[0038] In addition, non-volatile memory chips can be implemented as, for example, flash memory, MRAM (magnetic RAM), STT-MRAM (spin-transfer torque MRAM), FRAM (ferroelectric RAM), PRAM (phase change RAM), RRAM (resistive RAM), etc., but are not limited thereto.

[0039] Logic chips can be implemented as, for example, microprocessors, graphics processors, signal processors, network processors, chipsets, audio codecs, video codecs, application processors, System on Chip, etc., but are not limited thereto.

[0040] A semiconductor chip (110) may include a semiconductor substrate (113) and a bonding pad (115). The semiconductor substrate (113) may have an upper surface and a lower surface facing each other. The semiconductor substrate (113) may include a semiconductor device (not shown).

[0041] A bonding pad (115) can be formed on a 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), but is not limited thereto.

[0042] 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 SiC (silicon carbide), GaAs (gallium arsenide), InAs (indium arsenide), InP (indium phosphide), etc. Alternatively, the semiconductor substrate (113) may have a silicon-on-insulator (SOI) structure. For example, the semiconductor substrate (113) may include a buried oxide layer. The semiconductor substrate (113) may include a conductive region, for example, an impurity-doped well or an impurity-doped structure. The semiconductor substrate (113) may have various device isolation structures, such as a shallow trench isolation (STI) structure.

[0043] A passivation layer (not shown) may be formed on the semiconductor substrate (113) to protect the semiconductor device 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).

[0044] An adhesive film (AF) is disposed 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 adhesive film (AF) may be, for example, a die attach film (DAF). Die attach films can be classified into inorganic adhesives and polymer adhesives, and there are also hybrid types made by mixing these two components.

[0045] The package substrate (210) may include a body portion (213) and a protective layer, serving as a support substrate and a mounting substrate. 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, etc. The package substrate (210) may be a printed circuit board. Of course, the package substrate (210) is not limited to a printed circuit board.

[0046] Internal wiring (not shown) may be formed on the package substrate (210), and the internal wiring may be electrically connected to the semiconductor chip (110) through a bonding wire (10) connected to a connection pad (215) on the upper surface of the package substrate (210).

[0047] When the package substrate (210) is a printed circuit board, the body portion (213) can typically be formed into a thin film by compressing a polymer material such as a thermosetting resin, an epoxy resin such as FR-4 (Flame Retardant 4), BT (Bismaleimide Triazine), ABF (Ajinomoto Build-up Film), or a phenolic resin to a certain thickness, and then applying copper foil to both sides and forming internal wiring, which is a transmission path for electrical signals, through patterning.

[0048] Meanwhile, printed circuit boards can be distinguished into single-layer PCBs, in which internal wiring is formed on only one side, and double-layer PCBs, in which internal wiring is formed on both sides. Additionally, by using an insulator called prepreg, the number of copper foil layers can be formed to three or more layers, and by forming three or more internal wirings according to the number of formed copper foil layers, a multi-layer structure PCB can be realized. Of course, the package board (210) is not limited to the structure or material of the printed circuit board described above.

[0049] A molding member (310) can be formed on a package substrate (210) to surround a semiconductor chip (110) and a bonding wire (10). The molding member (310) can be formed, for example, from an epoxy molding compound.

[0050] In contrast, the molding member (310) is not limited to epoxy molding compound and can be formed from various materials, such as epoxy-based materials, thermosetting materials, thermoplastic materials, UV-treated materials, etc. In the case of thermosetting materials, it may include phenolic, acid anhydride, and amine-type curing agents and acrylic polymer additives.

[0051] A molding member (310) is formed by injecting an appropriate amount of molding material onto a package substrate (210) through an injection process and forming the outer shape of a 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 the delay time between the injection of the molding material and the pressurization, the amount of molding material injected, and the pressurization temperature / pressure can be set by considering physical properties such as the viscosity of the molding material. The side and top surfaces of the molding member (310) may have a right-angle shape.

[0052] Although not shown, a marking pattern containing information of the semiconductor chip (110), such as a barcode, QR code, number, character, symbol, etc., may be formed on the side and / or upper surface of the molding member (310).

[0053] The molding member (310) can serve to protect the semiconductor chip (110) and the bonding wire (10) from external influences such as contamination and shock. To perform this role, the thickness of the molding member (310) can be formed to at least surround both the semiconductor chip (110) and the bonding wire (10). Since the molding member (310) covers the entire package substrate (210), the width of the molding member (310) can be substantially the same as the width of the semiconductor package (100).

[0054] A bonding wire (10) formed by a wire bonding method according to the technical concept of the present invention may be formed to electrically connect a bonding pad (115) and a connection pad (215). At least one of a control signal, a power signal, and a ground signal for the operation of a semiconductor chip (110) may be provided from the outside through the bonding wire (10). Additionally, a data signal 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.

[0055] Although the bonding wire (10) is exemplarily shown disposed on only one side of the semiconductor chip (110), the placement of the bonding wire (10) is not limited thereto. For example, the bonding wire (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).

[0056] The bonding wire (10) can be connected by either a thermo compression connection or an ultrasonic connection, and can also be connected by a thermosonic connection method that combines the thermo compression connection and the ultrasonic connection methods.

[0057] The 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 be in direct contact with the upper surface of the bonding pad (115). The neck portion (13) may be positioned on the upper surface of the ball portion (11). The stitch portion (17) may be positioned to be in direct contact with 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 formed to be joined by a ball bonding method, and the connection pad (215) and the bonding wire (10) may be formed to be joined by a stitch bonding method.

[0058] As the integration density of semiconductor chips (110) required by electronic devices increases recently, the number of bonding wires (10) included in the semiconductor package (100) is increasing. Therefore, a fast operating speed of the bonding equipment for forming the bonding wires (10) is required.

[0059] Accordingly, the wire bonding method according to the technical concept of the present invention described below can ultimately increase the manufacturing efficiency of the semiconductor package (100) and improve productivity and economic efficiency by resolving the temporary suspension of the bonding equipment due to contamination of the portion where the wire (10P) is bonded at the connection pad (215) and increasing the operating rate of the bonding equipment.

[0060] FIG. 3 is a flowchart illustrating a wire bonding method for a semiconductor package according to one embodiment of the technical concept of the present invention.

[0061] A wire bonding method for a semiconductor package according to the technical concept of the present invention may include the following process sequence. Where an embodiment can be implemented differently, a specific process sequence may be performed differently from the order described. For example, two processes described consecutively may be performed substantially simultaneously, or may be performed in the reverse order of the described sequence.

[0062] Referring to FIG. 3, a wire bonding method (S10) is shown, comprising a first step (S110) of forming a first bond on a bonding pad, a second step (S120) of forming a wire loop, a third step (S140) of forming a second bond on a connection pad, a fourth step (S450) of detecting the degree of contamination of the portion where the wire is bonded on the connection pad (215), a fifth step (S560) of forming a free air ball on the tip of the wire (10P), and a sixth step (S160) of preventing the wire (10P) from coming off.

[0063] In the wire bonding method (S10) according to the technical concept of the present invention, if the part where the wire is bonded at the connection pad (215) is determined not to be contaminated according to the detection result of the fourth step (S140) of detecting the degree of contamination of the wire (i.e., if 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.

[0064] If it is determined that the part where the wire (10P) is bonded at the connection pad (215) is contaminated (i.e., if a defect occurs), the process proceeds to the 6th step (S160) to prevent the wire (10P) from coming off, and then proceeds to the 5th step (S150) to form a free air ball at the tip of the wire, thereby completing one cycle of the wire forming process normally.

[0065] That is, the wire bonding method (S10) according to the technical concept of the present invention can increase the manufacturing efficiency of a semiconductor package and improve productivity and economic efficiency by designing each step to detect whether the wire is contaminated in order to resolve the temporary suspension of the bonding equipment due to contamination of the part where the wire (10P) is bonded at the connection pad (215).

[0066] FIG. 4 is a flowchart specifically illustrating a wire bonding method of a semiconductor package of FIG. 3, and FIG. 5 to 18 are process diagrams illustrating the process sequence of a semiconductor package according to one embodiment of the technical concept of the present invention.

[0067] Referring to FIG. 4, the wire bonding method (S20) according to the technical concept of the present invention specifically describes a step for detecting whether the portion where the wire is bonded at the connection pad is contaminated before the capillary rises at the connection pad. If the portion where the wire is bonded at the connection pad is contaminated (i.e., if a defect occurs), the wire clamp can be changed to a closed state to prevent the wire from detaching from the capillary.

[0068] Therefore, when the wire formation process is carried out using the wire bonding method (S20), a continuous process is possible without temporarily stopping the bonding equipment even if a defect occurs during the process, so the operating rate of the bonding equipment can be significantly increased. Accordingly, the manufacturing efficiency of the semiconductor package can be increased, and productivity and economic efficiency can be improved.

[0069] 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) may be interposed 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).

[0070] A capillary (CA) may be positioned above the bonding pad (115) at a certain distance. A portion of the wire (10P) may protrude from the center hole of the capillary (CA).

[0071] 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 is provided to the wire (10P) protruding from the center hole of the capillary (CA) so that the bottom of the wire (10P) can be melted. Accordingly, a free air ball (10F) can be formed at the bottom of the wire (10P) in the center hole of the capillary (CA).

[0072] Instead of an electric spark, ultrasonic energy or thermal energy may be provided to the bottom of the wire (10P). The wire (10P) may be restricted from moving inside the capillary (CA) by the closing action of the wire clamp (WC).

[0073] 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) can come into contact with 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).

[0074] In this case, the free air ball (10F, see FIG. 4) can be compressed between the capillary (CA) and the bonding pad (115) to form a ball portion (11) and a neck portion (13) at the bottom of the wire (10 P). 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). A ball bonding method bonding 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 smaller than the diameter of the ball portion (11), so that the neck portion (13) may be positioned to be fully seated on the upper surface of the ball portion (11).

[0075] Referring to FIG. 7, the capillary (CA) can be moved vertically upward from the upper surface of the bonding pad (115) to expose the neck portion (13) and the wire (10P) to the outside of the capillary (CA). The capillary (CA) can be moved vertically upward to be positioned at a height corresponding to a predetermined distance from the bonding pad (115). The wire (10P) can form a wire portion (15) that extends vertically from the upper surface of the neck portion (13) by the open state of the wire clamp (WC).

[0076] Referring to FIGS. 4 and FIGS. 8, with the wire clamp (WC) holding the wire (10P), the capillary (CA) can be moved to the connection pad (215) of the package substrate (210) corresponding to the bonding pad (115) (step S220). That is, the capillary (CA), which has been moved upward in a vertical direction from the bonding pad (115), can 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 bottom of the capillary (CA) can be extended along the sliding of the capillary (CA).

[0077] Through this, a 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 breaking. That is, by bonding the wire (10P) to the connection pad (215), a bonding wire (10) connecting the bonding pad (115) and the connection pad (215) is formed (step S230).

[0078] 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).

[0079] Before the capillary (CA) moves upward from the connection pad (215), the height of the capillary (CA) can be measured by measuring the rotation angle of the drive motor in the encoder (EN) (step S250). In other words, the encoder (EN) can measure the height of the capillary (CA) that guided the wire (10P) when the wire (10P) is bonded to the connection pad (215) (step S250).

[0080] When the portion where the wire (10P) is bonded to the connection pad (215) becomes contaminated, contaminants are formed on the connection pad (215), so the capillary (CA) is positioned at a higher location than when the connection pad (215) is not contaminated. 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 can determine that contaminants have formed on the portion where the wire is bonded to the connection pad (215), and if the height of the capillary (CA) measured by the encoder (EN) is the same as the height of the reference capillary, it can determine that contaminants have not formed on the portion where the wire is bonded to the connection pad (215) (step S260).

[0081] Referring to FIG. 9, when it is confirmed that the portion of the wire (10P) bonded to the connection pad (215) is not contaminated, the wire clamp (WC) releases the fixation of the wire (10P), and the capillary (CA) can move upward in a vertical direction from the upper surface of the connection pad (215). The wire (10P) can be extended while in contact with the contact point (CP) of the connection pad (215). That is, if no defect occurs in this way, the wire (10P) can protrude outside the capillary (CA) and be electrically connected to the connection pad (215).

[0082] Referring to FIG. 10, as the capillary (CA) moves continuously upward while the wire clamp (WC) is open, the wire (10P) is completely severed from the stitch portion (17), thereby forming a bonding wire (10) that electrically connects the bonding pad (115) and the connection pad (215). A stitch bonding can be implemented in which the stitch portion (17), which is part of the bonding wire (10), is adhered to the connection pad (215).

[0083] 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) may rise to a level corresponding to the electronic flame-off height, and a new free air ball (10F, see FIG. 15) may be formed at the bottom of the wire (10P) through the process of FIG. 15 described later. That is, one cycle of the wire forming process is normally completed, and the capillary (CA) may proceed with or wait for a new cycle of the wire bonding process.

[0084] Referring to FIG. 11, if it is confirmed that the part where the wire (10P) is bonded to the connection pad (215) is contaminated before the capillary (CA) rises from the connection pad (215) (i.e., if a defect occurs), the wire clamp (WC) can be changed to a closed state to prevent the wire (10P) from coming off the capillary (CA).

[0085] If the height of the measured capillary (CA) is greater than the reference capillary height, or if the difference between the height of the measured capillary (CA) and the reference capillary height is greater than a preset value, a wire breakage prediction signal is generated in the detection module (6), and the control module (8) can control the wire clamp (WC) to fix the wire (10P) according to the wire breakage prediction signal.

[0086] Accordingly, the wire clamp (WC) is changed to a 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 kept in an open state, the wire (10P) is not fixed and the wire (10P) can detach from the capillary (CA) as the wire (10P) is wound up by the tension of the reel, causing the wire (10P) to break due to contamination.

[0087] Referring to FIGS. 12 and 13, when the wire clamp (WC) is closed, the capillary (CA) moves upward in a vertical direction from the upper surface of the connection pad (215), thereby separating a portion of the wire (10P) from the connection pad (215). By doing so, a bonding wire (10) can be formed to electrically connect the bonding pad (115) and the connection pad (215). A stitch bonding can be implemented in which a stitch portion (17), which is part of the bonding wire (10), is adhered to the connection pad (215).

[0088] However, unlike what is shown in FIG. 8, the tip (19) of the wire (10P) is not protruding from the capillary (CA) but is located inside the capillary (CA), and a free air ball cannot be formed on the tip (19) of the wire (10P).

[0089] Referring to FIG. 1, the wire clamp (WC) is changed to an open state, and the capillary (CA) is vibrated up and down so that the tip (19) of the wire (10P) protrudes outside the capillary (CA). By vibrating the capillary (CA) up and down using the vibration device (VB), the tip (19) of the wire (10P) can protrude outside the capillary (CA) and move downward in the direction where the connection pad (215) is located. During the process of vibrating the capillary (CA) up and down, ultrasonic vibration may be added to the capillary (CA). However, the ultrasonic vibration may not be performed as necessary.

[0090] Referring to FIGS. 15 and 16, a new free air ball (10F) can be formed at the bottom of the wire (10P). An electric spark is provided to the bottom of the wire (10P) protruding from the center hole of the capillary (CA) using a discharge electrode (BT), so that the bottom of the wire (10P) can be melted. Accordingly, a new free air ball (10F) can be formed at the bottom of the wire (10P) in the center hole of the capillary (CA). Instead of an electric spark, ultrasonic energy or thermal energy may be provided to the bottom of the wire (10P). That is, one cycle of the wire forming process is normally completed, and the capillary (CA) can proceed with or wait for a new cycle of the wire bonding process.

[0091] A wire (10P) having a free air ball (10F) formed thereon can be moved onto a new bonding pad (not shown) of a semiconductor chip (110). A state can be provided in which a wire (not shown) can be continuously formed to electrically connect the bonding pad and a new connection pad (not shown) of a package substrate (210).

[0092] Although embodiments according to the technical concept of the present invention have been described above 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 those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical concept or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. Explanation of the symbols

[0093] 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

Claim 1 A capillary for guiding a wire; a wire clamp for controlling the supply of the wire by fixing or releasing the wire; a capillary transfer unit for moving the capillary so that the wire is bonded to a bonding pad of a semiconductor chip on a package substrate, and transferring the capillary so that when one side of the wire is bonded to the bonding pad, the other side of the wire is bonded to a connection pad of the package substrate; a drive motor for driving the capillary transfer unit; and an encoder connected to the drive motor to measure the rotation angle of the drive motor, and measuring the height of the capillary relative to the connection pad when the other side of the wire is bonded to the connection pad. A wire bonding device comprising: a detection module that detects the degree of contamination of the portion where the other side of the wire is bonded at the connection pad by comparing the height of the measured capillary with a preset reference capillary height; wherein the detection module generates a wire breakage prediction signal when the height of the measured capillary is greater than the reference capillary height; and further comprising a control module that is electrically connected to the detection module and controls the wire clamp to fix the wire according to the wire breakage prediction signal. Claim 2 In claim 1, the package substrate is arranged along the X-axis direction, and the encoder is a wire bonding device that measures the height of the capillary in the Z-axis direction. Claim 3 delete Claim 4 In claim 1, the wire breakage prediction signal is a wire bonding device generated when the difference between the height of the measured capillary and the height of the reference capillary is greater than a preset value. Claim 5 delete Claim 6 A wire bonding method comprising: bonding the leading end of a wire supplied through a wire clamp and a capillary to a bonding pad of a semiconductor chip on a package substrate; moving the capillary to a connection pad of the package substrate corresponding to the bonding pad while the wire clamp is fixed, bonding the wire to the connection pad to form a bonding wire connecting the bonding pad and the connection pad; releasing the wire from the wire clamp, and an encoder measuring the height of the capillary relative to the connection pad; and detecting the degree of contamination of the portion of the wire bonded at the connection pad by comparing the measured height of the capillary with a preset reference height of the capillary; wherein detecting the degree of contamination includes generating a wire breakage prediction signal when the measured height of the capillary is greater than the reference height of the capillary, and further comprising controlling the wire clamp to fix the wire according to the wire breakage prediction signal. Claim 7 delete Claim 8 A wire bonding method according to claim 6, wherein the wire breakage prediction signal is generated when the difference between the height of the measured capillary and the height of the reference capillary is greater than a preset value. Claim 9 A wire bonding method according to claim 6, further comprising raising the capillary when the wire breaks while the wire clamp is fixed. Claim 10 A wire bonding method according to claim 6, wherein detecting the contamination level further comprises, when the difference between the height of the measured capillary and the height of the reference capillary is smaller than a preset value, maintaining the wire clamp in a state where the wire is released from fixation and raising the capillary from the connection pad, and after the wire clamp fixes the wire, further raising the capillary. Claim 11 delete

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