KR100370861B1 - Method and apparatus for manufacturing engineering balls with high precision and high yield - Google Patents

Abstract

The present invention flows out from the spray tank through the orifice and crushed and dropped by the vibration of the vibrating device to form droplets, spherical form, cooling, and solidification, such as metal ball or ceramic ball such as solder ball for the BIS / SIP package In the production of engineering balls of high precision, high precision and high yield engineering balls manufacturing method and apparatus which can precisely manufacture the size, sphericity and surface roughness of the engineering balls, and thus can significantly increase the yield. To provide.

The manufacturing method of the main engineering ball is a charger which is arrange | positioned in the position where a droplet falls, and removes the defect by adhesion of the droplet which falls from the orifice 21a, and maximizes a yield, and a predetermined positive or negative voltage is applied. Exerting an electric repulsion force between the falling droplets by passing the droplets falling from the orifice (21a) and charging them with electrostatic charges (22); The electrostatic charge is charged by the deflector 23 to which the predetermined voltage is applied so as to further prevent the contact or partial fusion between the droplets electrically repelling and dropping by the electrostatic charge by electric or magnetic force to completely separate the droplets from each other. And deflecting the droplets with each other.

Description

TECHNICAL AND APPARATUS FOR MANUFACTURING ENGINEERING BALLS WITH HIGH PRECISION AND HIGH YIELD

The present invention relates to a method and a device for manufacturing an engineering ball with high precision and high yield, and more particularly, to a liquid flowing out of an injection tank through an orifice while heating molten metal, and crushed and dropped by vibration of a vibrating device. In the manufacture of engineering balls, such as metal balls or ceramic balls, such as solder balls for ball grid array / chip scaled packages by forming, spheroidizing, cooling, and solidifying the enemy, The present invention relates to a method and apparatus for manufacturing an engineering ball of high precision and high yield capable of precisely manufacturing the size, sphericity, surface roughness, and the like of the engineering ball, and thereby significantly increasing the yield.

Conventionally, the chip or substrate 1 according to the present invention has a ball fusion land 3 for electrical contact in a predetermined arrangement, as shown in plan view in FIG. Balls 5 are respectively attached to the ball fusion lands 3 so as to form electrical contact therewith. In a ball grid array / chip scaled package having a solder ball having such a structure, the solder ball is fused by applying heat by hot air or the like after placing it on an external device or a substrate. Therefore, since the electrical contact with the external device or the substrate is completed, it is convenient to form an electrical contact, which has been widely adopted in recent years.

In the manufacture of such solder balls, there is a cut wire method in which the cut wire is melted and dispersed in cooling oil at a predetermined temperature, but there are difficulties in terms of complicated manufacturing process (34 processes in total) and production cost. In addition, there is a problem that the quality is poor, such as largely dispersed spherical particle size and sphericity.

In order to solve this problem, the molten metal from the storage tank or the injection tank is passed through the orifice by vibrating to form droplets, and is prepared by coagulation. In particular, contamination is prevented by preventing contact with oxygen during the solidification process. In order to prevent and improve the sphericity, metal balls such as solder balls for BZ / SPI packages have been manufactured by solidifying by dropping molten metal droplets in an oil or inert gas atmosphere.

In these devices, the droplets flow out from the orifice of the injection tank during the downward movement of the piston by the existing vibrating device and stop the outflow of the droplets from the injection tank during the upward movement, and thus drop the falling droplets. After forming the size and sphere, it is cooled to form a ball.

In addition, the metal ball is 37Pb-63Sn, 36Pb-2Ag-62Sn, 95Pb-5Sn, 95Pb-1.5Ag-3.5Sn, In-48Sn, In-5Ag-15Pb, Sn-10Ag, Sn-3.5Ag and Sn-1Pd It has been limited to solder balls having any one composition of.

However, the above-described conventional methods aim to produce a large quantity of metal balls such as high quality solder balls and continuously, but still have a large amount of defective products mixed with good products to improve size, sphericity, surface roughness, and the like. There is a problem that the work to be inspected is not difficult and the productivity is lowered, and the yield is lowered due to a large amount of defects.

Accordingly, the present invention is to solve this problem, while flowing molten metal through the orifice from the spray tank while heating the molten metal, and broken by dropping by dropping by the vibration of the vibrating device to form, spherical, cooled, solidified In the manufacture of engineering balls such as metal balls or ceramic balls, such as solder balls for A / SPI packages, the size, sphericity and surface roughness of the engineering balls can be precisely manufactured, and the yield can be significantly increased. It is an object of the present invention to provide a method and apparatus for manufacturing a high precision and high yield engineering ball.

1 is a plan view showing an arrangement of lands of a chip or a board with a ball according to the present invention;

Figure 2 is a schematic cross-sectional view showing a feature configuration of one embodiment of a manufacturing device of a high precision engineering ball according to the present invention;

3 is a block diagram for explaining a feature configuration of an embodiment of a control device for a manufacturing method of a high precision engineering ball according to the present invention;

4 is a flow chart showing an example of a drive control method of the vibration device of FIG.

<Description of the symbols for the main parts of the drawings>

1: chip or board

3: ball fusion land 5: ball

10: molten metal supply device 13: molten metal supply pipe

13 ': flow control means 14: level sensor

15: thermocouple 20: manufacturing apparatus of the engineering ball

21: injection tank 21 ': heater

22: charger 22a: charger control unit

23: deflector 23a: deflector control unit

30: inner container 30a: temperature sensing means

31: outer container 31a: oxygen detection means

32: flow means 32a: flow means control unit

32b: heater 32c: cooler

32d: heater controller 32e: cooler controller

34: discharge means 35: storage container

36: gas tank 36a: differential pressure valve

37: oil tank 38: oil filling line

39: exhaust pump 40: vibration device

41: vibrator control unit 42: lamp

43: image acquisition means 44: A / D conversion unit

45: computer (main control unit) 50: bad ball recovery system

51: gutter 51a: height sensing means

51b: temperature sensing means 52: feedback means (motor pump)

52a: feedback means control unit 53: feedback line

54: heating means 54a: heating means control unit

In order to achieve the above object, the manufacturing method of the high precision and high yield engineering ball according to one embodiment of the present invention, by heating the molten metal through the orifice from the injection tank while heating the molten metal by crushing and falling by the vibration of the vibration device In the manufacturing method of engineering balls, such as metal balls or ceramic balls, such as solder balls for ball grid array / chip scaled packages by forming, spherical, cooling, and solidifying droplets. To eliminate the defects due to the adhesion between the drops falling from the orifice to maximize the yield, the drop is disposed in the position to drop, passing through the drops falling from the orifice between the charger is applied a predetermined positive or negative voltage Exerting an electric repulsive force between the falling droplets by charging with an electrostatic charge; The droplets charged by the electrostatic charge by the deflector to which the predetermined voltage is applied are separated from each other by the electric force or the magnetic force to further prevent the contact or partial fusion between the droplets electrically repulsed by the electrostatic charge by the electric force or the magnetic force. And deflecting.

In addition, the present invention, the step of acquiring the image of the drop falling from the injection tank by the image acquisition means such as a camera; A ball image is extracted by a computer (main control unit) from the acquired droplet image, and data such as size, spherical degree, and surface roughness are acquired from the ball image, and the data falls within the reference value range related to size, sphericity, surface roughness, and the like. Determining whether it is determined; Dropping the droplets into the gutter by controlling the deflector control unit and the deflector so as not to deflect in the deflecting step or to deflect the deflecting step so as to be regarded as a failure when it is not in the reference value range in the determining step; In addition, when the determination step does not belong to the reference value range, the control unit may further include controlling the frequency, amplitude, waveform mode, and the like of the vibration device through the vibration device control unit.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a schematic cross-sectional view of a feature configuration of an embodiment of the manufacturing device 20 of the high precision engineering ball according to the present invention, Figure 3 is a control device for the manufacturing method of the high precision engineering ball according to the present invention A feature configuration of one embodiment of the present invention is described as a block diagram, and FIG. 4 shows an example of a control method of the vibrator control unit 41 of FIG. 3 as a flowchart.

2 and 3, the manufacturing apparatus of the high precision and high yield engineering ball according to the present invention, while flowing the molten metal through the orifice (21a) from the injection tank 21 while heating the molten metal as in the prior art and the vibration device 40 It is configured to fall by crushing by vibration of the charger 22, the deflector 23, the image acquisition means 43, the computer (main control unit) 45 and to ensure high precision and high yield in accordance with the present invention and Each control unit, the bad ball recovery system 50, rotary type discharge means 34, the oil tank 37 and the oil filling line 38 is configured to include.

As the vibrator 40, an electric vibrator such as a piezo element may be used, and it is more uniform to form a droplet having a piston-like diaphragm 40 'near the orifice 21a in the injection tank 21. It is desirable to be able to transmit the vibration uniformly. In addition, the molten metal in the injection tank 21 is a constant temperature, pressure, flow by the thermocouple 15, level sensor 14, flow control means 13 ', heater 21' and heater control unit 21 ". It is preferable to maintain the state of a stable fluid and the like in order to form the same and uniform droplets.

The charger 22 applies an electric repulsion force to the droplets falling by charging the droplets falling from the orifice 21a with electrostatic charge, and further deflects by deflecting the droplets charged by the deflector 23 to further fall. Contact or partial fusion between the droplets is prevented to completely separate the droplets from each other. Accordingly, it is possible to maximize the yield by removing the defects due to the adhesion between the droplets falling from the orifice 21a. Further, the charger 22 and the deflector 23 are charged by the computer 45 according to the size, spherical shape and surface roughness of the ball through the charger control unit 22a and the deflector control unit 23a through the charge amount and deflecting amount thereof. It is preferably configured to be controlled. Such control by the computer 45 is preferable not only for setting control of the frequency, amplitude, waveform mode, etc. of the vibrator 40 at the time of initial setting, but also applicable to intermediate defect inspection and control.

To this end, the image acquisition means 43 is installed to acquire the image of the drop falling from the injection tank 21 and output the image signal or image data, as shown in FIG. In this case, it is input to the computer 45 through the A / D conversion unit 44, and the computer 45 extracts a ball image from the image signals or image data of the acquired droplets, and the size and sphericity of the ball image. Data is obtained, such as surface roughness, to determine whether it falls within the reference value range for size, spherical roughness and surface roughness. In this process, the previously developed data acquisition method can be applied.

As a result, when it does not belong to the reference value range, the deflector control unit 23a and the deflector 23 shown in Figs. It is configured to control the frequency, amplitude, waveform mode and the like of the vibration device 40 via the vibration device control unit 41.

The image acquisition means 43 may be provided with a lamp 42 to effectively acquire the image of the ball, three units may be installed to effectively acquire a three-dimensional image, but the present invention is not limited thereto.

In addition, the defective ball recovery system 50 including at least feedback means (motor pump) 52 and feedback line 53 to flow the defective engineering balls collected by the gutter 51 to the molten metal supply device (7). By being installed, the operation can be carried out continuously without interruption. To this end, a height detecting means 51b for detecting a collection state of the defective ball is installed, and the feedback is collected through the feedback line 53 by operating the feedback means 52 through the feedback means control unit 52a. The engineered balls can be flowed to the molten metal supply device (7). Since the balls are not melted because they are fine balls, they may be configured to ensure the fluidity by installing the heating means 54, the temperature sensing means 51a and the heating means controller 54a, if necessary.

In addition, in Figure 2, the flow means to improve the sphericity and surface roughness and reduce defects by minimizing the drop resistance caused by the fluid when the droplet is dropped through the inert gas or oil through the injection tank 21 ( 32) is installed. In the case of falling into the oil, it is composed of an inner container 30 for filling the oil and an outer container 31 for holding the inert gas atmosphere, but when the ball is manufactured by dropping the droplet into the inert gas, The inner container 30 is unnecessary, and only by forming the lower end of the outer container 31 together with the lower end of the inner container 30 in FIG. 2, the collection of the balls becomes easy and the discharge to the outside is also easy. .

The flow means 32 may be a fan or a pump for imparting fluidity to the inert gas or oil of the inner container 30. In addition, it is preferable that the flow control unit 32a is provided to be variably controlled according to the determination result from the data such as the size, the sphericity, the surface roughness, and the like of the ball image. In addition, the temperature sensing means 30a, the heater 32b, the cooler 32c, the heater control unit 32d and the cooler control unit 32e to control the temperature of the oil or gas in the inner container 30 as shown in FIG. It can be provided. As a result, not only the spherical shape and surface roughness but also proper coagulation can be further minimized.

On the other hand, it is preferable to provide a rotary discharge means 34 at least the discharge passage is closed to discharge the good ball to enable continuous operation. The rotary discharge means 34, the plurality of rotary partition 34a is intermittently rotated in one direction via the discharge control unit 34a, the ball of good quality stacked on the upper storage container (from the lower container 30) 35) and the oil refill line to replenish oil in the space between the rotary partition 34a of the discharge means 34 on the opposite side from which the engineering ball is discharged, when the ball is dropped into the oil. By providing 38, it is desirable to minimize the influence on the fluidity of the oil by space and to prevent downtime.

In addition, in order to prevent harmful oxidation of the ball, the oxygen sensing means 31a senses the amount of oxygen in the outer container 31, and when the amount of oxygen is excessive, exhausts it to the exhaust pump 39 so that the gas tank ( Inert gas flows into the outer container 31 from the inside 36 and the oxygen sensing means 31a, the gas tank 36, and the differential pressure valve so as to suppress the amount of oxygen in the outer container 31 and maintain a constant pressure. 36a) and an exhaust pump 39 are provided. In addition, when the amount of oxygen is increased, since it affects the sphericity, it is preferable that the amount of oxygen is detected so as to be controlled to maintain the minimum amount.

The operation and action of the manufacturing apparatus of the high precision and high yield engineering ball of this invention comprised in this way are demonstrated with the manufacturing method of this invention as follows.

Also in the present invention as in the prior art, droplets are formed, spherical and cooled by flowing out of the injection tank 21 through the orifice 21a while heating the molten metal and crushing and dropping by the vibration of the vibrator 40. And solidifying to manufacture engineering balls, such as metal balls or ceramic balls, such as solder balls for Ball Grid Array / Chip Scaled Package. By charging the droplets falling from 21a to the electrostatic charge by the charger 22, the electrical repulsive force is exerted between the falling droplets, and the droplets falling further by displacing the charged droplets by the deflector 23 are in contact with each other. To prevent partial fusion and to completely separate the droplets from each other. Accordingly, the yield can be maximized. The thermocouple 15, the level sensor 14, the flow rate control means 13 ', the heater 21', and the heater control part 21 "maintain a constant temperature, pressure, flow, and the like in a stable fluid state. And evenly drop the molten metal as the amount of molten metal dropped through the flow rate control means 13 'instead of replenishing the molten metal by the level sensor 14. It may be supplied to the injection tank 21 through the molten metal supply pipe 13 to maintain a constant pressure in the orifice 21a.

In addition, as shown in FIG. 4, the image of the droplet falling from the injection tank 21 is acquired by the image acquisition means 43, and the ball image is extracted by the computer 45 from the acquired droplet image. From the ball image, data such as size, sphericity and surface roughness are obtained to determine whether the data falls within a reference value range regarding size, spherical roughness, surface roughness, and the like. In the judging step, the deflector 23 is not deflected or deflected by the computer 45 via the deflector control unit 23a for deficiency or vice versa when it does not belong to the reference value range. By controlling, the droplet is dropped into the gutter 51.

In addition, when it does not belong to the reference value range in this way, the frequency, amplitude, waveform (sine wave, square wave, etc.) mode, etc. of the vibrator 40 are controlled via the vibrator control part 41, and size, squareness, and surface roughness are also controlled. Adjust your back. In FIG. 4, only the control of variables such as the frequency, amplitude, waveform (sine wave, square wave, etc.) mode of the vibration device 40 by the image acquisition means 43 is shown in a simplified flow chart, but FIGS. 2 and 3 As shown in FIG. 6, all factors influencing size, sphericity, surface roughness, etc. may be controlled by the computer 45 or a direct control unit in a manner similar to that of FIG. 6.

In addition, by flowing the oil or gas filled in the inner container 30 by the flow means 32 to the drop speed of the droplets to minimize the resistance of the fluid due to the drop of the droplets to prevent deformation until solidification, Accordingly, by increasing the sphericity and surface roughness, it is possible to reduce defects and maximize the yield. The flow velocity of the fluid is also controlled by the flow control means 32a according to the image determination result by the computer 45, so that the droplets can be dropped in a more optimal atmosphere.

On the other hand, the good ball is collected in the lower portion of the inner container 30, by intermittently rotating the rotary type discharge means 34 of the good ball accumulated on the top of the rotary partition 34a of the discharge means 34 The inner container 30 is discharged to the lower storage container 35. When the ball falls into the oil, the oil is replenished in the space between the oil tank 37 and the rotary partition 34a of the discharge means 34 on the opposite side from which the engineering ball is discharged from the oil filling line 38. At one time it is possible to minimize the influence on the fluidity of the oil of the inner container 30 to prevent failure. In addition, even when an inert gas is filled in the inner container 30, the gas may be filled instead of oil so as not to contaminate the inside of the inner container 30.

In addition, the bad engineering balls collected by the gutter 51 are feedback means (motor pump) 52, feedback line 53, height sensing means 51b, temperature sensing means 51a, heating means 54, heating By the bad ball recovery system 50 including the means control unit 54a and the like flows to the molten metal supplying device 7, further operation can be continuously performed without interruption.

According to the configuration and operation of the manufacturing method and the apparatus of the high precision and high yield engineering ball according to the embodiment of the present invention described above, using the image acquisition means 43, the computer 45, the flow means 32 By controlling the vibrator 40 and the like, it is possible to precisely manufacture the size, sphericity, and surface roughness of the engineering ball, and also to minimize the defects, thereby significantly increasing the yield, as well as the gutter. By the configuration of the 51, the defective ball recovery system 50, the discharge means 34, and the like, there is no interruption of the operation, thereby maximizing productivity.

Claims (9)

While the molten metal is heated, it flows out of the injection tank 21 through the orifice 21a, and is crushed and dropped by the vibration of the vibrator 40 to form droplets, spherical shapes, cooling, and solidifying the BZ / SI. In the manufacturing method of engineering balls, such as metal balls or ceramic balls, such as solder balls (Ball Grid Array / Chip Scaled Package), The orifice 21a is disposed between the chargers 22 at which the droplets are dropped so as to maximize the yield by removing defects caused by the adhesion between the droplets falling from the orifices 21a, and to which a predetermined positive or negative voltage is applied. Exerting an electrostatic repulsion force between the falling droplets by passing the droplets falling from the ground) and charging the electrostatic charges; The electrostatic charge is charged by the deflector 23 to which the predetermined voltage is applied so as to further prevent the contact or partial fusion between the droplets electrically repelling and dropping by the electrostatic charge by electric or magnetic force to completely separate the droplets from each other. A method of manufacturing a high precision and high yield engineering ball, characterized in that it comprises a step of deflecting each other droplets. 2. The method according to claim 1, wherein the image acquisition means (43) acquires an image of the falling droplets between the acting of the electrical repulsive force between the falling droplets and the deflecting; Extracting a ball image from the enemy image by the computer 45, and acquiring data such as size, sphericity, and surface roughness from the ball image to determine whether it falls within a reference value range regarding size, sphericalness, surface roughness, and the like. Further includes; The computer (main control unit) to deflect in the deflecting step to treat as defective when it does not belong to the reference value range in the judgment step, or to deflect when deflecting good products or vice versa. (45) controlling the deflector control unit (23a) and the deflector (23) to drop the droplet into the gutter (51); When the determination step does not belong to the reference value range, and further comprising the step of controlling the frequency, amplitude, waveform mode, etc. of the vibrator 40 via the vibrator control unit 41 further comprises a high precision Method of manufacturing engineering balls of high degree and high yield. delete delete While the molten metal is heated, it flows out of the injection tank 21 through the orifice 21a, and is crushed and dropped by the vibration of the vibrator 40 to form droplets, spherical shapes, cooling, and solidifying the BZ / SI. In the manufacturing apparatus of engineering balls, such as metal balls or ceramic balls, such as solder balls (Ball Grid Array / Chip Scaled Package), In order to remove the defects caused by the adhesion of the droplets falling from the orifice 21a to maximize the yield and to pass the droplets falling from the orifice 21a and to charge the electrostatic charge by dropping the electrostatic force between the falling droplets A charger 22 disposed at a position where the enemy falls, to which a predetermined positive or negative voltage is applied; Of the charger 22 in order to deflect the electrostatically charged droplets by electric or magnetic forces so as to further prevent contact or partial fusion between the droplets electrically repelling and dropping by the electrostatic charge to completely separate the droplets from each other. High precision and high yield engineering ball production apparatus characterized in that it comprises a deflector (23) installed in the lower portion is applied a predetermined voltage. 6. The image capturing means (43) provided in the lower portion of the charger (22) for acquiring an image of droplets falling from the injection tank (21) and outputting an image signal or image data. A charger control section (22a) for controlling the amount of charged charges to the droplets falling by falling, and a deflector control section (23a) for controlling the deflecting amount by the deflector (23); Extracting a ball image from the obtained image signal or image data of the droplet, and obtaining data such as size, spherical degree, surface roughness, etc. from the ball image to determine whether it falls within the reference value range for size, spherical degree, surface roughness, , The deflector control unit 23a and the deflector 23 are controlled so as to fall into the gutter 51 by the deflector 23 to treat as defective when not in the reference value range, and also via the vibrator control unit 41. And a computer (45) for controlling the frequency, amplitude, and waveform mode of the vibration device (40). delete delete delete