KR100650944B1 - Flip-chip bonder for concentratly heating - Google Patents

Abstract

A flip chip bonder apparatus with a high density heater is provided to heat quickly an aiming portion and to prevent an unnecessary loss of the heat by using a light guide panel and a convex type lens. A flip chip bonder apparatus includes a heating tip(1) and a radiation type heating unit(4) for heating the heating tip under the heating tip. The flip chip bonder apparatus further includes a light guide panel and a convex type lens. The light guide panel(13) is installed on the radiation type heating unit in order to endow a radiative beam and a reflective beam with directional properties. The convex type lens(9) is installed on the light guide panel. The convex type lens is used for focusing the radiative beam onto the heating tip by refracting the radiative beam.

Description

Flip-chip bonder with high density heater {Flip-Chip bonder for concentratly heating}

1 is a perspective view showing a conventional flip chip bonder device having a radiant heating unit previously filed by the present applicant, and FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

3 is a cross-sectional view of a high density heating unit of a flip chip bonder according to a preferred embodiment of the present invention.

4 is a cross-sectional view illustrating a state in which a cooling fin 14 is additionally mounted on an inner case of a flip chip bonder according to a preferred embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: heating tip 1a: insulation

2: outer case 3: inner space

4: halogen lamp 5: reflector

6: body support 7: inlet

8: inner case 9: convex lens

10: cooling gas 11: lamp support

12: outlet

The present invention relates to a flip chip bonder device, and more particularly, by employing a light guide plate and a convex lens in the path of radiant light without improving the performance of a halogen lamp itself, to improve the high density rapid heating performance by concentrating radiant heat in a local area of the heating plate. Improving the productivity by forcibly introducing the cooling gas around the heating part after the bonding operation to rapidly cool the heating part, and heat insulation material is added to the periphery of the heating plate to facilitate rapid heating and rapid cooling of the heating plate The present invention relates to a flip chip bonder having a high density heater capable of preventing thermal damage of a peripheral device.

The heating method of a flip chip bonder of the general flip chip bonding method is a solder ball on an electrode pattern or an inner lead of a chip in a process of manufacturing an optical module or a semiconductor chip. Or it refers to a method of electrically connecting by making a protrusion such as a solder bump (Solder Bump) and placing a chip on the substrate (substrate) and heat bonding.

In other words, unlike the conventional wire bonding or soldering method, the flip chip bonding forms a metal pad on the surface of the device to be bonded with the substrate and pre-solds the solder bumps on one metal pad or both metal pads of the substrate or the device to be bonded. After forming, the solder material is heated and melted while the corresponding solder bumps of the substrate and the devices to be bonded are faced to each other so that the substrate and the devices are bonded to each other.

In the conventional flip chip bonding method, a method of heating and melting the solder material includes a thermocompression method and a laser compression method depending on the heating means. The thermocompression method includes solder bumps formed on a chip of a carrier substrate. After moving to the bonding position (Bonding Position) to face the solder bump formed in the designated position and pressurized while heating the chip from the back of the chip, the heating material to the melting point of the bonding material arranged between the solder bump of the chip and the solder bump of the substrate At the same time, by pressing at the same time between the two solder bumps.

In addition, the laser crimping method is similar to the thermal crimping method described above, and the solder bumps of the chip are moved to the bond position so as to face the designated solder bumps of the carrier substrate. It has also been disclosed in the Republic of Korea Patent Publication No. 2001-108103 by heating.

Meanwhile, in the various flip chip heating methods described above, the present applicant has a bonding device for heating the flip chip using a halogen lamp having a low thermal inertia and having a very short heating time as a heating means (Korean Patent Application No. 10-A). 2003-0051335) has been previously filed, which will be described with reference to FIGS. 1 and 2 as follows.

1 is a perspective view showing a conventional flip chip bonder device having a radiant heating unit filed by the present applicant, and FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1.

According to FIG. 1, a conventional flip chip bonder is a silicon substrate having an alignment groove (not shown) for alignment with a flip chip, and a heating plate 21 disposed on an upper surface thereof, and installed below the heating plate to heat the heating plate. In the flip chip bonder device having a heating unit 20, the heating unit generates heat and at the same time a halogen lamp 22 for generating infrared rays penetrating through the alignment grooves of the flip chip and the silicon substrate, and the halogen lamp It comprises a socket 24 for supplying power by inserting both terminals of the lamp and a reflector 23 for reflecting heat generated from the halogen lamp having a lamp mounting portion spaced apart from the lower side and both sides of the halogen lamp.

 The operation sequence of the flip chip bonder configured as described above is the radiant light emitted by first turning on the flip chip (not shown) to be bonded to the heating plate 21 and then turning on the halogen lamp 22 which is the radiant heating unit 20. Silver is made of SiC material with excellent heat conductivity and heat absorption, and proceeds directly to the heating plate 21 having high radiation absorption rate and the heating plate fixing plate 25 designed to have low radiation absorption rate, or is reflected by hitting a reflector 23 processed into a mirror surface. The heating plate 21 proceeds.

The radiant light absorbed by the heating plate 21 is directly converted into heat due to the characteristics of the material. The speed is much higher than that of a device heated by conduction or convection. Thus, the heating plate 21 rapidly heats up the flip chip placed on the heating plate. By heating, it is possible to bond at the proper temperature.

In the conventional flip chip bonding apparatus, the heating plate fixing plate 20 separately installed for fixing the heating plate has an advantage that the radiant heat absorption coefficient is lower than that of the heating plate 21 so that the heating plate fixing plate 20 is not rapidly heated like the heating plate and thus unnecessary heat loss does not occur. Although it has a function of concentrating heat, it has a limitation in controlling heating rate and heating temperature in heating performance. Accordingly, there has been a technical problem to improve the performance and lifetime of halogen lamps for rapid heating of the heating part, which is a major variable to increase productivity. In addition, the incidental heat generated due to the limitation of the cooling effect by the natural cooling method affects the peripheral devices, which is a deterrent to precision bonding.

Therefore, it is possible to realize improved rapid heating performance without improving the performance of the existing halogen lamp itself, and to combine the rapid cooling performance by the forced cooling method to minimize the effect on the peripheral devices. It is desirable to develop a flip chip bonding device that can maximize productivity in a series of production processes.

In order to solve the above problems, an object of the present invention is to propose a flip chip bonder capable of high-speed heating by concentrating heat in a small region of a heating plate.

Another object of the present invention is to provide a flip-chip bonder that has a heating plate that is rapidly heated, thereby significantly reducing defects such as cold soldering and at the same time rapidly cooling around the heating plate, thereby improving work efficiency with cracked heat distribution. It aims to propose a device.

In order to solve the above technical problem, a flip chip bonder having a high density heater according to the present invention includes a heating tip (1) positioned at an upper surface of the chip so that the chip is placed and bonded to each other, and a lower side of the heating tip (1). In the flip chip bonder device is provided with a radiant heating unit 4 for heating the heating tip 1, the radiant light and the reflected light generated in the heating unit is located above the radiant heating unit 4 It includes a light guide plate 13 to have a straightness and a convex lens 9 which is located on the light guide plate and refracting the radiated light so that the radiation light passing through the light guide plate is concentrated at a position of the heating tip formed by a predetermined distance apart. Provided is a flip chip bonder device having a high density heater.

In addition, the heating tip is insulated by the heat insulating material is mounted on the side, the flip chip bonder is provided with a cooling gas 10 inlet on one side of the outer surface of the flip chip bonder and the outlet of the cooling gas 10 on the other side of the flip chip bonder. Cooling by forced circulation of the cooling gas 10, it is preferable that the cooling fins 14 are spaced apart at regular intervals on the outer surface of the flip chip bonder in order to increase the cooling efficiency by the cooling gas (10). .

The inner spaces 3a, 3b, and 3c on the path where the radiant light emitted from the radiant heating part 4 proceeds to the heating tip through the light guide plate 13 and the convex lens 9 are rapidly maintained by maintaining the vacuum state. Heating and rapid cooling can be achieved.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals in the drawings refer to like elements, and the size of each component in the drawings may be exaggerated for clarity and convenience of description.

3 is a cross-sectional view of the high density heating unit of the flip chip bonder according to the preferred embodiment of the present invention. 3, 4 and 5 are all shown in a cross-sectional view, which is a cross-sectional view based on the perspective view of FIG. 1 shown in the prior art so that the overall technology according to the present invention can be implemented by those skilled in the art by explaining the cross-sectional detail in detail. Of course, it can be described.

The heating unit includes an inner case 8 and an outer case 2, and a body having a hollow portion to allow the cooling gas 10 to flow in and out between the inner case 8 and a U curved below the inner case. Reflective plate 5 which is formed in a curved shape and is mirror-processed so that light can be reflected, Halogen lamp 4 located above the reflector to emit radiant light for heating, and Halogen lamp Refracting a light guide 13 positioned at an upper portion of the light guide 13 and providing a straightness to radiation emitted directly from the halogen lamp or reflected on the reflecting plate, and a light having a straightness through the light guide plate. And a convex lens 9 for concentrating on the small area and a heating tip 1 provided at a position corresponding to the small area.

 The bonding apparatus according to the present invention is for a flip chip bonder requiring an ultra-high precision alignment of about 1 mm. Since the flip chip bonding is performed at a high temperature of 300 degrees or more, accurate alignment and fast heating time are essential to maintain accuracy. It is a joining device whose drawing is 1 mm or less. The heating section of the present invention uses a halogen lamp with fast heating performance. The halogen lamp fixing part 11 is located at the bottom of the halogen lamp to support the halogen lamp.

A reflector plate positioned below the halogen lamp and fixed to the inner case at the end thereof may be a shape suitable for reflecting upward the heat of the halogen lamp radiated downward. In the present invention, it may have a U-shaped curved surface curved downward or a hemispherical curved surface as a modified embodiment.

The light guide is a thin and transparent plate which serves to guide light provided from a light source in a predetermined direction, and is mainly a light guide panel 13 manufactured by injection molding acrylic (PMMA), or other optical isomers A polarizing plate 13 is used, which is an optical mechanism that is made of a thin film and selectively transmits or refracts the transmitted light to selectively transmit linearly polarized light in a specific direction. As described above, the light guide member is positioned at an upper portion of the halogen lamp and mounted inside the inner case to allow light generated directly from the halogen lamp and light reflected from the reflector to pass therethrough.

In addition, the polarizing plate may be made of natural stone such as tourmaline or amethyst, or a polaroid having high light transmittance by using a single crystal called herapathite as a thin film. Of course, it is preferable that various other equivalents are possible.

In addition, the reflective plate 5 is polished to polish the surface of the metal material in order to reflect the radiant light traveling in the opposite direction to the upper direction by mirror processing, or aluminum or zirconia having a low radiation absorption rate and thermal conductivity. It may be manufactured using a zirconia material, and a lamp fixing part 11 is inserted in the center of the reflector to improve the durability of the device by fixing the halogen lamp. In addition, the lamp fixing part minimizes and fixes the space, and the other space can be utilized as a reflector curved surface on which the light generated from the halogen lamp is reflected.

The upper portion of the light guide plate is provided with a convex lens to collect the light straight from the light guide plate in one place. As it passes through the convex lens, it is known that the parallel light serves to focus at a point called a focal point. The convex lens is mounted on the inner wall of the inner cable at both ends. At the top of the lens is a heating tip, where the heating tip is located where the focus of the convex lens is located. In the present invention, the focus of the convex lens is preferably positioned at the bottom of the heating tip, but the focus of the convex lens may be positioned at the center of the heating tip.

In addition, as shown in FIG. 4, an inlet 7 is formed at one side of the outer case adjacent to the heating tip to allow the cooling gas 10 to be introduced into the hollow part, and the inlet at the other side of the outer case. Cooling gas 10 introduced through the flow through the periphery of the inner case is formed in the outlet 12 so as to cool the heating portion and to be discharged to the outside by a rapid heating followed by rapid cooling in a series of bonding operations Productivity can be maximized.

In addition, the cooling fins 14 may be additionally installed on the outer circumferential surface of the inner case to widen the heat transfer area in contact with the cooling gas 10 and the inner case so that the heating part may be cooled more effectively. Instead of the direct cooling method in which the gas 10 and the cooling fins 14 are directly contacted and cooled, an indirect cooling method may be employed, and the shape of the cooling fins 14 may be variously modified in the skill level of those skilled in the art. will be.

Here, it is preferable that a heat insulator 1a is inserted into the body so as to be provided around the heating tip to fix the heating tip and at the same time to insulate the heating tip, in which heat generated by heating of the heating tip by a halogen lamp is flip-chip. In order to concentrate more on the purpose of rapid heating and to minimize the heat transfer to the peripheral devices.

In addition, the heat insulator is installed like a wrap around the heating tip, but is installed in various forms through an optimized design on the remaining side except for the light receiving area where the radiant light is concentrated and the heating area where the flip chip is located. The material also has a low thermal conductivity, so that inorganic asbestos, glass, quartz, diatomaceous earth, pearlite, etc., which can be used at high temperatures Can be used.

On the other hand, the speed of light in a specific medium is the value of the speed of light multiplied by the inverse of the refractive index. In the vacuum state, the refractive index is "1", which maximizes the speed of the radiant light. By preventing the phenomenon, radiant light can be effectively used at less loss and minimum internal heat generation.

Therefore, the interior spaces 3a, 3b, and 3c on the path where the radiated light emitted from the halogen lamp passes through the light guide plate 13 and the convex lens 9 to the heating tip are preferably maintained in a vacuum state.

5 is a cross-sectional view of another embodiment configured to be utilized as a general iron which is a small hammer-like device mainly used for soldering by the lower heating bonding method and the upper heating bonding method as in the preferred embodiment of the present invention.

That is, in addition to the method of bonding the flip chip to the upper surface of the heating tip as described above, in addition to pressing the bonding portion of the flip chip from the top to the bottom through another embodiment of the present invention by pressing at the same time to bond the electrical components It can be used in the production process of heat pressing method.

Hereinafter, an operation state of the heating unit of the flip chip bonding apparatus according to the preferred embodiment of the present invention will be described.

When the flip chip to be bonded is placed on the heating tip 1, the halogen lamp 4 fixed by the halogen fixing part 11 is turned on, and the radiated light emitted through the halogen lamp is directly reflected by the radiation and the reflector. The reflected and scattered radiation is directed toward the light guide plate in the upward direction in the interior space 3.

The light propagated in the upward direction passes through the light guide plate 13 and has a straightness and is incident perpendicularly to the convex lens, and is concentrated at a focal point formed at a predetermined distance while passing through the convex lens 9. As such, the heating tip 1 is positioned at the point where the focal point is formed, and thus, more improved radiated light can be obtained without improving the performance of the halogen lamp.

In addition, in order to remove the heat generated in the body by the operation of the halogen lamp is provided with an inlet (7) through which the cooling gas 10 can be introduced around the circumference of the insulated heating tip, through which the cooling gas 10 is It flows into the hollow part between an outer case and an inner case by the method of forced ventilation.

As such, the cooling gas 10 forced into the inlet of the outer case flows around the heating tip and flows along the inner case of the main body to cool the heating unit, and then the temperature is raised to be forced out through the outlet so that the heating unit is naturally cooled. It is cooled by the forced cooling method instead of the rapid cooling method.

As described above, the device has the advantage of being able to concentrate the radiant light rapidly compared to the prior art, which can rapidly heat a small area. This advantage reduces heat loss and prevents damage to mechanical objects around. In addition, it has the effect of reducing the capacity of the heat source, which will also benefit economically.

While the invention has been described and illustrated in connection with a preferred embodiment for illustrating the principles of the invention, the invention is not limited to the construction and operation as shown and described. Rather, it will be apparent to those skilled in the art that many changes and modifications to the present invention are possible without departing from the spirit and scope of the appended claims. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention.

As described above, the flip chip bonder device according to the present invention is not only capable of high-speed heating due to heat concentration in a small area, and also has a function of condensing radiant light, thereby providing an effect of preventing unnecessary heat loss.

In addition, it is possible to prevent the problem caused by heat in the peripheral device by adopting the insulation of the heating chip and the efficient forced cooling method, and has the advantage of improving the work efficiency by enabling rapid heating and rapid cooling.

Claims (5)

The flip tip is provided with a heating tip 1 positioned on an upper surface of the chip to be placed and bonding, and a radiant heating part 4 installed below the heating tip 1 to heat the heating tip 1. In the chip bonder, The light guide plate 13 positioned above the radiant heating unit 4 to allow the radiation light and the reflected light generated from the heating unit to have a straightness, and the light guide plate positioned above the light guide plate and spaced apart from the light guide plate by a predetermined distance. And a convex lens (9) for refracting radiant light so as to be concentrated at a position where the heating tip is formed. The method of claim 1, The heating tip is a flip chip bonder having a high-density heater, characterized in that the heat insulating material is mounted on the side (1a). The method of claim 1, The interior spaces 3a, 3b, 3c on the path where the radiant light emitted from the radiant heating part 4 proceeds to the heating tip through the light guide plate 13 and the convex lens 9 are characterized in that the vacuum state. Flip chip bonder with high density burner made. The method of claim 1, Cooling gas 10 inlet on one side of the outer surface of the flip chip bonder device and a cooling gas 10 outlet on the other side of the outer side of the flip chip bonder is cooled by the forced circulation of the cooling gas (10). Flip chip bonder with high density burner. The flip chip having a high density heater according to claim 3, wherein the cooling fins (14) are spaced apart at regular intervals on the outer surface of the flip chip bonder to increase the cooling efficiency by the cooling gas (10). Bonder device.

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