WO2022124780A1 - Bonding head and bonding device having same - Google Patents

Abstract

A bonding head comprises: a base block; an air block arranged on the base block; and a heating block arranged on the air block, and provided to generate heat and heat a chip, wherein the air block cools the heating block while using the air as a medium to suppress the transmission of the heat generated from the heating block to the base block.

Description

Bonding head and bonding device having same

Embodiments of the present invention relate to a bonding head and a bonding apparatus having the same. More particularly, embodiments of the present invention relate to a bonding head provided to pick up a chip and bond it to a substrate, and a bonding apparatus including the bonding head.

Recently, in order to respond to the demand for miniaturization of electronic components including semiconductor packages, a technology for forming a stacked chip package by stacking a plurality of electronic components has been developed.

The stacked chip package is a semiconductor package in which chips are stacked on a substrate. The stacked chip package is formed through a bonding process in which heat and pressure are applied while the chips and the substrate are stacked. A bonding apparatus is used to perform the bonding process.

The bonding apparatus supports the substrate with a chuck structure, places the chip on the substrate with a bonding head, and applies heat and pressure to the chip. Specifically, the bonding head bonds the chip to the substrate by heating the chip in a state in which the chip is in close contact with the upper surface of the substrate to melt bumps provided on the lower surface of the chip, and then cooling the chip again.

In general, the bonding head includes a heating block, a base block, and a ceramic member interposed between the heating block and the base block.

The heating block is made of a material having excellent thermal conductivity, such as silicon carbide having its own electrical resistance or aluminum nitride with a high melting point metal (tungsten, molybdenum) heating element embedded therein. Meanwhile, the ceramic member is made of a material having relatively low thermal conductivity compared to the heating block, such as aluminum oxide (Al ₂ O ₃ ).

The ceramic member is made of a material having relatively low thermal conductivity, such as aluminum oxide (Al ₂ O ₃ ). Accordingly, the ceramic member suppresses heat generated in the heating block from being transferred to the base block. Accordingly, the bonding head can implement a relatively fast heating rate. However, as the ceramic member made of aluminum oxide has a thermal conductivity of 28 to 32 W/(m·K), the ceramic member has a limit in suppressing heat generated in the heating block from being transferred to the base block. .

In addition, the ceramic member may retain heat therein. That is, the ceramic member made of aluminum oxide may have a relatively high specific heat as it has a relatively low thermal diffusivity.

That is, the ceramic member does not easily transfer the heat generated from the heating block to the base block, but may retain the heat that is not diffused therein. Therefore, when the bonding process of melting the bump provided on the lower surface of the chip and then cooling it again is performed, it is difficult for the bonding apparatus to rapidly cool the bump due to the heat retained by the ceramic member.

Furthermore, when a chip having a fine pitch between bumps is bonded to a substrate, a temperature adjacent to the melting point of the solder needs to be precisely controlled. Therefore, when overheating occurs in the solder, misalignment between the chip and the substrate may occur.

In the bonding apparatus, it is necessary to secure electrically stable bonding properties while maintaining a target shape of a solder ball or bumper connecting an electrical signal between a chip and a substrate. Therefore, the bonding apparatus needs to simultaneously implement a relatively fast heating rate and a cooling rate.

Embodiments of the present invention provide a bonding head capable of implementing a relatively excellent heating rate and cooling rate.

Embodiments of the present invention provide a bonding apparatus having the bonding head.

The bonding head according to embodiments of the present invention includes a base block, an air block disposed on the base block, and a heating block disposed on the air block to generate heat to heat the chip And, the air block is provided to cool the heating block while suppressing the transfer of heat generated in the heating block to the base block using air as a medium.

In an embodiment of the present invention, the air block cools the heating block using an upward airflow in which the air rises from the lower portion of the air block toward the lower surface of the heating block.

In one embodiment of the present invention, the air block, the body disposed on the base block and extending upward from the body, the heating block is spaced apart from the lower surface of the body to support the heating block columns The body may include an inlet and an outlet, and the inlet may include an inlet and an inlet passage communicating with the inlet.

Here, the discharge unit may include an outlet and a discharge passage that communicates the inlet and the outlet.

In addition, the separation distance between the outlet and the lower surface of the heating block may be in the range of 4 to 12 mm. The discharge passage may have a diameter of 5 to 15 mm. Furthermore, the diameter ratio of the inlet passage and the outlet passage may be 1:1 to 1:1.5.

Meanwhile, the inlet and the outlet may communicate in an “L” shape. In addition, at least one pair of the inlet and outlet may be provided. Alternatively, the inlet and outlet may be provided in two or more pairs, and each pair may be arranged at equal intervals.

In addition, the body may be made of SUS or Invar material.

Meanwhile, each of the columns may include one of a vacuum line formed therein to transmit a vacuum force to a structure positioned above the heating block and a wiring line for transmitting power to the heating block.

Here, the air block may further include a connecting bar connecting the columns and a flange extending in a radial direction from the connecting bar to guide the flow of the air.

In an embodiment of the present invention, the heating block may include a heating element that is built in and generates heat by power applied from the outside.

In one embodiment of the present invention, the heating block is provided to surround the heating element and the heating element provided therein as a whole, may include a cover made of aluminum nitride.

In one embodiment of the present invention, the lower surface of the heating block may have a larger exposed area than the non-exposed area.

In an embodiment of the present invention, the heating block has a surface roughness of 0.5 Ra or less and may have a first surface supporting the chip and a second surface facing the first surface and blasted.

In one embodiment of the present invention, a suction plate provided on the heating block and provided to adsorb the chip is additionally provided, and the heating block is formed to pass through each in a vertical direction, and the chip and the suction plate are formed to pass through. and a first vacuum line and a second vacuum line for providing a vacuum force to respectively adsorb, and the suction plate may include a vacuum hole provided to communicate with the second vacuum line to provide a vacuum force to the chip. can

In one embodiment of the present invention, the heating block may be made of a ceramic material, and the air block may be made of a metal material.

The bonding head according to embodiments of the present invention includes an air block and a heating block disposed on the air block and provided to generate heat to heat the chip, and the air block uses air as a medium Thus, it is possible to cool the heating block at a cooling rate of 100° C./sec or more while suppressing the transfer of heat generated in the heating block to the lower portion of the air block.

A bonding apparatus according to embodiments of the present invention includes a chuck structure supporting a substrate and a bonding head provided to be movable above the chuck structure and bonding a chip to the substrate, wherein the bonding head is a base a block, an air block disposed on the base block, and a heating block disposed on the air block to generate heat to heat the chip, the air block using air as a medium It may be provided to cool the heating block while suppressing the transfer of heat generated in the heating block to the base block.

The bonding head according to the present invention includes an air block for thermally insulating the base block from the heating block by using air as a medium between the base block and the heating block, and cooling the heating block. The air block may suppress the transfer of heat for heating the chip to the base block. Furthermore, the heating block may be rapidly cooled using air supplied from the outside. The bump between the chip and the substrate can be quickly heated and cooled.

The bonding apparatus according to the present invention may stably bond the chip to the substrate using the bonding head and the chuck structure.

1 is a cross-sectional view for explaining a bonding head according to an embodiment of the present invention.

FIG. 2 is a plan view for explaining the air block shown in FIG. 1 .

3 is a front view for explaining the air block shown in FIG.

FIG. 4 is a plan view for explaining the heating block shown in FIG. 1 .

FIG. 5 is a cross-sectional view illustrating the heating block shown in FIG. 1 .

6 and 7 are graphs illustrating cooling time.

8 is a configuration diagram for explaining a bonding apparatus according to an embodiment of the present invention.

9 is a plan view of the chuck structure shown in FIG. 8 .

FIG. 10 is a plan view for explaining the chuck plate shown in FIG. 8 .

11 is a bottom view for explaining the chuck plate shown in FIG. 8 .

12 is an enlarged cross-sectional view of a portion A illustrated in FIG. 8 .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention should not be construed as being limited to the embodiments described below and may be embodied in various other forms. The following examples are provided to sufficiently convey the scope of the present invention to those skilled in the art, rather than being provided so that the present invention can be completely completed.

In embodiments of the present invention, when an element is described as being disposed or connected to another element, the element may be directly disposed or connected to the other element, and other elements may be interposed therebetween. it might be Conversely, when one element is described as being directly disposed on or connected to another element, there cannot be another element between them. Although the terms first, second, third, etc. may be used to describe various items such as various elements, compositions, regions, layers and/or portions, the items are not limited by these terms. will not

The terminology used in the embodiments of the present invention is only used for the purpose of describing specific embodiments, and is not intended to limit the present invention. Further, unless otherwise limited, all terms including technical and scientific terms have the same meaning as understood by one of ordinary skill in the art of the present invention. The above terms, such as those defined in ordinary dictionaries, shall be interpreted to have meanings consistent with their meanings in the context of the related art and description of the present invention, ideally or excessively outwardly intuitive, unless clearly defined. will not be interpreted.

Embodiments of the present invention are described with reference to schematic diagrams of ideal embodiments of the present invention. Accordingly, changes from the shapes of the diagrams, eg, changes in manufacturing methods and/or tolerances, are those that can be fully expected. Accordingly, the embodiments of the present invention are not to be described as being limited to the specific shapes of the areas described as diagrams, but rather to include deviations in the shapes, and the elements described in the drawings are entirely schematic and their shape It is not intended to describe the precise shape of the elements, nor is it intended to limit the scope of the present invention.

1 is a cross-sectional view for explaining a bonding head according to an embodiment of the present invention. FIG. 2 is a plan view for explaining the air block shown in FIG. 1 . 3 is a front view for explaining the air block shown in FIG.

1 to 3 , the bonding head 100 according to an embodiment of the present invention corresponds to a unit that picks up a chip 10 , transfers it onto a substrate, and bonds the chip on the substrate.

The bonding head 100 includes a base block 110 , an air block 120 , and a heating block 130 . Although not shown, the bonding head 100 may be provided to enable horizontal movement, elevating movement, rotation, inversion, and the like for the transfer of the chip 10 .

The base block 110 is made of a metal material. An example of the metal material may be stainless steel. The base block 110 may be mechanically connected to a driving unit (not shown) to transport the chip 10 .

The air block 120 is provided on the base block 110 . The air block suppresses transfer of heat generated from the heating block 130 to the base block 110 by using air as a medium or cools the heating block 130 .

The heating block 130 is disposed on the air block 120 . The heating block 130 is provided to heat the chip 110 by generating heat.

In more detail, the air block 120 suppresses heat transfer to the base block 110 or cools the heating block 130 using air as a medium.

That is, the air has a very low thermal conductivity of 0.025 W/(m·K) in a state of 1 atm and 293K (=20° C.). For comparison, aluminum oxide (Al ₂ O ₃ ), which is a material of a generally used ceramic member, has a thermal conductivity of 28 to 32 W/(m·K). Therefore, compared to a ceramic block made of aluminum oxide (Al ₂ O ₃ ) material, the air block 120 using the air as a medium according to embodiments of the present invention reduces the heat generated in the heating block 130 by about 1,100 times to 1,280 times blocking may have an excellent thermal blocking efficiency.

Meanwhile, the air block 120 may cool the heating block using a cooling fluid flowing toward the heating block 130 , for example, air or an inert gas.

The air corresponds to the process air provided in a general process facility. For example, the air may be provided at a flow rate of 120 L/min. and a pressure of 0.5 MPa at a temperature of room temperature (RT).

At this time, the air block 120 may cool the heating block 130 by using an upward airflow in which the air rises from the lower portion of the air block 120 toward the lower surface of the heating block 130 . . As the air of the updraft collides with the lower surface of the heating block 130 and then spreads in the radial direction, it is possible to effectively cool the entire area of the lower surface of the heating block 130 .

As a result, the air block 120 may cool the heating block 130 while suppressing transfer of the heat generated in the heating block 130 to the base block 110 .

In one embodiment of the present invention, the air block 120 includes a body 121 and columns 126 in which the inlet 122 and the outlet 124 are formed.

The body 121 is disposed on the base block 110 . That is, the body 121 may be located on the upper surface of the base block 110 .

The body 121 may be made of SUS or Invar material. Accordingly, since the body 121 has a relatively low coefficient of thermal expansion, deformation due to heat generated during a high-temperature chip bonding process may be suppressed.

The columns 126 extend upwardly from the body 121 . The columns 126 extend from, for example, four edges of the outer portions of the body 121 . The columns 126 may all have the same vertical height. Accordingly, the columns 126 are in contact with the lower surface of the heating block 130 . Accordingly, the columns 126 may support the heating block 130 so that the heating block 130 is spaced apart from the lower surface of the body 121 .

In addition, the columns 126 may be arranged at equal intervals to each other. In addition, the columns 126 may be arranged at an equal angle with respect to the body 121 . Meanwhile, the columns 126 may be arranged at any height and spacing according to the shape of the heating block 130 or the arrangement angle of the heating block 130 .

Air may flow in the space formed between the body 121 and the heating block 130 . Accordingly, the air block 120 can thermally insulate the adjacent base block 110 from the heating block 130 using air as a medium and cool the heating block 130 .

A maximum load of 150 N may be applied to the heating block 130 during the chip bonding process. At this time, the columns 126 are provided in plurality, for example, two or more, so that the air block 120 can support the load applied to the heating block 130 .

The body 121 includes an inlet 122 and an outlet 124 that communicate with each other to provide a flow path through which air flows.

The inlet 122 may be formed on one side of the body 121 . The inlet 122 provides a flow path through which air can be introduced into the body 121 . The inlet 122 includes an inlet 122a and an inlet passage 122b communicating with the inlet 122a and extending in a horizontal direction. That is, the inlet 122 may have a shape extending in a horizontal direction. However, the inlet passage 122b is not necessarily limited to extending in a horizontal direction, and may extend obliquely with respect to the upper surface of the body 121 .

The discharge part 124 may be formed in the center of the body 121 . The discharge unit 124 provides a flow path through which air can be discharged to the outside of the body 121 . The discharge part 124 includes a discharge port 124a and a discharge passage 124b communicating with the discharge port 124a and extending in a vertical direction or an inclined direction. The discharge passage 124b communicates with the end of the inlet passage 122b and the outlet 124a.

The discharge unit 124 is formed in the center of the body 121, so that the air discharged from the discharge unit 124 rises toward the center of the heating block 130, and then radiates from the center of the lower surface of the heating block 130. direction can spread. Accordingly, cooling efficiency of the heating block 130 may be increased.

Meanwhile, the inlet 122 and the outlet 124 may communicate in an “L” shape. Accordingly, as the fluid resistance through which the cooling air flows is reduced, the inlet 122 and the outlet 124 cause the cooling air to flow into the body 121 from the outside, and then to remove the introduced air from the center of the body 121 . It can be discharged upwards.

Also, the discharge passage 124b may have a diameter of 3 to 15 mm. When the exhaust passage 124b has a diameter of less than 3 mm, the flow of cooling air is not smooth, whereas when the exhaust passage 124b has a diameter of more than 15 mm, the exhaust passage 124b is The exhaust pressure of the air discharged from the outlet 124a via the air may be excessively reduced, so that the cooling efficiency of the heating block 130 may be reduced.

Meanwhile, the diameter ratio (Dout/Din) of the discharge passage 124b to the inflow passage 122b may be 1:1 to 1:1.5. Accordingly, the cooling air flowing in from the inlet 122a through the inlet passage 122b and the outlet passage 124b may flow more smoothly.

In one embodiment of the present invention, at least one pair of the inlet 122 and the outlet 124 is provided. For example, the inlet 122 and the outlet 124 may be provided in two or more pairs, and each pair may be arranged at equal intervals.

In particular, when the first vacuum line 134 for transferring the vacuum force to the chip 10 is formed in the center of the body 121 , the inlet 122 is formed around the first vacuum line 134 . ) and two pairs of the discharge unit 124 may be disposed to correspond to each other. Accordingly, the cooling air flowing in from the inlet 122 formed on both sides of the body 121 is provided uniformly over the entire lower surface of the heating block 130 at an increased flow rate through the outlet 124. can

Referring to FIG. 2 , four columns 126 may be provided at each of the four edge portions of the body 121 . In this case, the pair of columns 126 may provide a second vacuum line 126a formed therein to transmit a vacuum force to the structure positioned above the heating block 130 . Meanwhile, the columns 126 in which the second vacuum line 126a is formed may be positioned to face each other. An example of the structure may be a suction plate 140 that is replaceably disposed on the upper portion of the heating block. Accordingly, the suction plate 140 may be fixed to the upper surface of the heating block 130 using the vacuum force provided through the second vacuum line 126a.

Meanwhile, the other pair of the columns 126 may include a wiring line 126b that transmits power to the heating block 130 . The columns 126 in which the wiring lines 126b are formed may be positioned to face each other. Accordingly, the wiring line 126b transmits power to the heating element 132 (refer to FIG. 5 ) included in the heating block 130 , so that the heating element 132 is driven to generate heat.

Referring to FIG. 3 , the air block 120 further includes a connecting bar 127 and a flange 128 .

The connecting bar 127 interconnects the columns 126 . The connecting bar 127 interconnects the columns 126 so that the air block 120 can secure improved durability against the load applied to the air block 120 .

Meanwhile, the flange 128 extends radially from the connecting bar 127 . The flange 128 may have an inclined sectoral shape. The flange 128 may guide the flow of the air. For example, the flange 128 may guide the cooling air falling downward to not be directed toward the adjacent bonding head 100 .

FIG. 4 is a plan view illustrating the heating block illustrated in FIG. 1 , and FIG. 5 is a cross-sectional view illustrating the heating block illustrated in FIG. 1 .

4 and 5 , the heating block 130 includes a heating element 132 and a cover part 135 .

The heating element 132 is built into the heating block 130 . The heating element 132 generates heat by power applied from the outside. For example, power supplied through the wiring line 126b among the columns 126 is applied to the heating element 132 . Accordingly, the heating element 132 may be driven to generate heat.

The cover part 135 is provided to completely surround the heating element 132 . The cover part 135 may be made of aluminum nitride. The aluminum nitride material may have a thermal conductivity of about 170 W/m·k or more. Accordingly, the heat generated by the heating element 132 may be effectively transferred to the chip 10 through the cover part 135 .

The heating block 130 has a first vacuum line 134 and a second vacuum line 136 extending to the top surface to provide a vacuum force.

The first vacuum line 134 and the second vacuum line 136 are not connected to each other, and the vacuum force is applied to each other.

For example, the first vacuum line 134 passes through the upper and lower portions of the central portion of the heating block 130 .

The second vacuum line 136 passes through the upper and lower portions of the edge portion of the heating block 130 . In particular, the second vacuum line 136 may be connected to a groove 135 formed in a predetermined length on the upper surface of the heating block 130 . Accordingly, the vacuum force provided through the second vacuum line 134 may act in a wider area with respect to the structure positioned above the heating block 130 .

For example, the first vacuum line 134 and the second vacuum line 136 may extend to the base block 110 . As another example, the second vacuum line 136 may communicate with the outlet 126c formed in the column 126 included in the air block 120 without extending to the base block 110 (see FIG. 3 ). ).

In one embodiment of the present invention, the lower surface of the heating block 130 may have an exposed area larger than the non-exposed area. Accordingly, the air positioned in the air block 120 between the heating block 130 and the base block 110 suppresses the transfer of heat generated in the heating block 130 to the base block 110 . Further, the cooling air provided by the air block 120 having the inlet 122 and the outlet 124 contacts the exposed area of the lower surface of the heating block 130, so that the heating block 130 is more can be effectively cooled. For example, the exposed area may have 60% or more of the lower surface.

In one embodiment of the present invention, the heating block 130 has a surface roughness of 0.5 Ra or less and a first surface 131 supporting the chip and a blasted product facing the first surface 131 . It may have two sides 136 . That is, as the first surface 131 has a relatively low surface roughness, leakage of vacuum force may be suppressed with respect to the structure on which the heating block 130 is positioned on the upper surface. Meanwhile, since the second surface 136 is blasted, a contact area with the cooling air is increased. Accordingly, the heating block 136 can be cooled more quickly by using the cooling air.

While the conventional air block is made of a ceramic material, for example, Al ₂ O ₃ material, the body 121 included in the air block 120 may be made of SUS or Invar material. Since the air block 120 including the body 121 is made of a material having a relatively low coefficient of thermal expansion, distortion of the air block 120 can be prevented in the high-temperature bonding process.

Furthermore, when the ceramic block made of Al ₂ O ₃ material is interposed between the heating block 130 and the base block 110 , the heat generated in the heating block 130 may be retained in the ceramic block for a predetermined time. In this case, since the heat retained in the ceramic block affects the heating block 130 , it is difficult to raise or cool the heating block 130 to a desired temperature. In order to solve this, a long cooling time is required to cool the ceramic block.

On the other hand, as the air block 120 supports the heating block 130 while being spaced apart between the heating block 130 and the base block 110, the cooling air supplied from the outside is supplied to the heating block 130 and It can flow easily in the spaced apart space between the base blocks (110). As a result, the cooling rate for the heating block 130 may be increased.

The suction plate 140 is provided on the heating block 130 . The suction plate 140 is fixed to the upper surface of the heating block 130 by the vacuum force of the second vacuum line 136 . The suction plate 140 may be replaced by providing a vacuum force to the second vacuum line 136 or releasing the vacuum force. Accordingly, when the suction plate 140 is damaged or contaminated, it is possible to easily respond to damage or contamination of the suction plate 140 by selectively replacing only the suction plate 140 .

In addition, the suction plate 140 has a vacuum hole 142 . The vacuum hole 142 is connected to the first vacuum line 134 of the heating block 130 . Accordingly, the chip 10 placed on the suction plate 140 may be fixed by the vacuum force provided through the first vacuum line 134 .

In a state in which the chip 10 is fixed with the suction plate 140 , the bonding head 100 may move to stack the chip 10 on the substrate. Also, the chip 10 may be pressed toward the substrate with the suction plate 140 .

The inlet 122 and the outlet 124 formed in the air block 120 use air to cool the heating block 130 to cool the chip 10 . As the chip 10 is cooled, the bumps of the chip 10 may be cooled to form solder. At this time, the air block 120 having the inlet 122 and the outlet 124 can cool the temperature of the heating block 130 from about 400° C. to about 100° C. within 3 seconds.

The bonding head 100 may further include a temperature sensor (not shown). The temperature sensor is provided inside the heating block 130 and senses the temperature of the heating block 130 . According to the detection result of the temperature sensor, it is possible to control on/off of power provided to the heating element 132 , injection of a cooling fluid in the cooling line 150 , and a refrigerant temperature and circulation. Meanwhile, the temperature sensor may be provided on the second surface or the suction plate 140 opposite to the first surface in contact with the suction plate 140 among the surfaces defining the heating block 130 .

The bonding head 100 transfers the chip 10 and heats the chip 10 with the heating block 130 in a state in which the chip 10 is brought into close contact with the substrate to melt the bump of the chip 10 . Thereafter, the bonding head 100 cools the chip 10 via the heating block 130 using the cooling air supplied from the air block 120 . Accordingly, a bonding process of bonding the chip 10 to the substrate is performed. Since the bonding head 100 rapidly heats and cools the chip 10 , it is possible to form solder of excellent quality and good shape between the substrate and the chip 10 .

6 and 7 are graphs illustrating cooling time.

6 and 7, a temperature cycle experiment comprising a temperature raising step of raising the temperature of the heating block from 100°C to 450°C, a holding step of maintaining the temperature for 5 seconds, and a cooling step of cooling from 450°C to 100°C again This was done. In this case, the time required for cooling from 450°C to 100°C in the cooling step is defined as the cooling time.

6 shows the cooling time according to the change in the separation distance between the lower surface of the heating block and the end of the outlet included in the air block.

Referring to FIG. 6 , it can be seen that when the separation distance is within the range of 4 to 12 mm, cooling time of less than 3 seconds is required. When the separation distance exceeds 12 mm, the cooling time exceeds 3 seconds because the air injected from the outlet does not effectively reach the lower surface of the heating block. On the other hand, when the separation distance is less than 4 mm, it can be confirmed that the cooling time exceeds 3 seconds because the air adjacent to the outlet is heated by the radiation phenomenon of heat generated from the heating block. Thereby, the heating block can be cooled at a cooling rate of 100° C./sec or more.

7 shows the cooling time according to the change in the diameter of the discharge passage included in the air block.

Referring to FIG. 7 , it can be seen that when the inlet passage formed in the air block has a diameter of 3 mm or more, it takes less than 10 seconds to cool down. When the diameter is less than 3 mm, it can be seen that the cooling efficiency is reduced as the cooling time exceeds 10 seconds.

8 is a configuration diagram for explaining a bonding apparatus according to an embodiment of the present invention. 9 is a plan view of the chuck structure shown in FIG. 8 . FIG. 10 is a plan view for explaining the chuck plate shown in FIG. 8 . 11 is a bottom view for explaining the chuck plate shown in FIG. 8 . 12 is an enlarged cross-sectional view of a portion A illustrated in FIG. 8 .

8 to 12 , the bonding apparatus 300 includes a bonding head 100 and a chuck structure 200 .

The bonding head 100 transfers the chip 10 onto the chuck structure 200 and bonds it to the substrate 20 , and includes a base block 110 , an air block 120 , a heating block 130 and the It includes a suction plate 140 . Although not shown, the bonding head 100 may be provided to enable horizontal movement, vertical movement, rotation, inversion, etc. for transferring the chip 10 .

A detailed description of the bonding head 100 is omitted because it is substantially the same as the bonding head 100 illustrated in FIGS. 1 to 5 .

In addition, the bonding head 100 may be disposed such that the suction plate 140 faces downward for bonding the chip 10 and the substrate 20 .

The chuck structure 200 supports the substrate 20 . In this case, a circuit pattern may be formed on the substrate 20 .

The chuck structure 200 includes a heating plate 210 , a chuck plate 220 , a guide ring 230 , a clamp 240 , a power cable 250 , and a temperature sensor 260 .

The heating plate 210 has a substantially circular plate shape, and contains a heating element 212 that generates heat by power applied from the outside.

The heating element 212 may be provided to form a predetermined pattern on the inner surface of the heating plate 210 . Examples of the heating element 212 include an electrode layer, a heating coil, and the like.

The heating plate 210 has a third vacuum line 214 and a fourth vacuum line 215 extending to the top surface. The third vacuum line 214 and the fourth vacuum line 215 may extend from a lower surface or a side surface of the heating plate 210 to the upper surface, respectively. The third vacuum line 214 and the fourth vacuum line 215 are not connected to each other, respectively. The third vacuum line 214 is connected to a vacuum pump (not shown), and provides a vacuum force for adsorbing the substrate 20 . The fourth vacuum line 215 is connected to a vacuum pump (not shown), and provides a vacuum force for adsorbing the chuck plate 220 .

The heating plate 210 has an alignment pin 216 on its top surface. The alignment pins 216 are for aligning the chuck plate 220 of the heating plate 210 , and a plurality of alignment pins 216 may be provided. The alignment pin 216 may be disposed on an edge of the upper surface of the heating plate 210 .

In addition, the heating plate 210 has a groove 218 formed along the upper surface edge. The groove 218 may be used to fix the guide ring 230 .

The chuck plate 220 has a substantially disk shape and is placed on the heating plate 210 . The chuck plate 220 supports the substrate 20 on its upper surface.

The chuck plate 220 has the fifth vacuum line 222 connected to the third vacuum line 214 for adsorbing the substrate 20 .

The fifth vacuum line 222 has a vacuum groove 222a and a plurality of vacuum holes 222b.

The vacuum groove 222a is formed in the lower surface of the chuck plate 220 . For example, the vacuum groove 222a may have a shape in which concentric grooves and radially extending grooves are combined with respect to the center of the lower surface of the chuck plate 220 or may have a circular groove shape. . At this time, the vacuum groove 222a does not extend to the edge of the lower surface of the chuck plate 220 in order to prevent leakage of the vacuum force.

While the chuck plate 220 is placed on the heating plate 210 , the vacuum groove 222a is defined by the upper surface of the heating plate 210 to form a space. Also, the vacuum groove 222a is connected to the third vacuum line 214 .

The vacuum holes 222b penetrate the chuck plate 220 and extend from the lower surface where the vacuum groove 222a is formed to the upper surface of the chuck plate 220 . The vacuum holes 222b are arranged to be spaced apart from each other. For example, the vacuum holes 222b may be arranged in a concentric circle shape or a radial shape.

Accordingly, the fifth vacuum line 222 is connected to the third vacuum line 214 , and the substrate 20 may be adsorbed by a vacuum force provided through the third vacuum line 214 .

Meanwhile, a distance between the vacuum holes 222b positioned at the outermost side of the chuck plate 220 may be relatively narrower than a distance between the vacuum holes 222b positioned at the innermost side of the chuck plate 220 . Specifically, the angle between the vacuum holes 222b positioned at the outermost shell may be half of the angle between the vacuum holes 222b positioned inside the outermost shell. For example, the angle between the vacuum holes 222b positioned at the outermost angle is about 15 degrees, and the angle between the vacuum holes 222b positioned inside the outermost shell can be about 30 degrees. have.

Accordingly, the vacuum force through the vacuum hole 212b may be stably provided even at the edge of the chuck plate 220 . Therefore, even at the edge of the chuck plate 220 , the substrate 20 may be in close contact with the chuck plate 220 , thereby preventing the substrate 20 from being lifted.

In addition, the chuck plate 220 has a vacuum groove 223 provided on its lower surface to be connected to the fourth vacuum line 215 so as to be vacuum-adsorbed by the heating plate 210 .

The vacuum groove 223 is formed in the lower surface of the chuck plate 220 . For example, the vacuum groove 223 may have a shape in which concentric grooves and radially extending grooves are combined with respect to the center of the lower surface of the chuck plate 220 , or may have a circular groove shape. . In this case, the vacuum groove 223 does not extend to the edge of the lower surface of the chuck plate 220 to prevent leakage of the vacuum force. Also, as shown in FIG. 5 , the vacuum groove 223 may be formed not to be connected to the fifth vacuum line 222 .

While the chuck plate 220 is placed on the heating plate 210 , the vacuum groove 223 is defined by the upper surface of the heating plate 210 to form a space. Also, the vacuum groove 223 is connected to the fourth vacuum line 215 .

The vacuum groove 223 is connected to the fourth vacuum line 215 , and the chuck plate 220 is in close contact with the heating plate 210 by vacuum force provided through the fourth vacuum line 215 . and can be fixed. Therefore, the substrate 20 on the chuck plate 220 may be supported flatly by minimizing distortion or bending of the chuck plate 220 .

The heating plate 210 and the chuck plate 220 may maintain a close contact state by the vacuum force provided through the fourth vacuum line 215 and the vacuum groove 223 . Therefore, a separate fastening member for fastening the heating plate 210 and the chuck plate 220 is unnecessary.

Also, the heating plate 210 and the chuck plate 220 may be separated and replaced by releasing the vacuum force provided through the third vacuum line 214 and the fourth vacuum line 215 . Therefore, the maintenance of the chuck structure 200 can be performed quickly.

On the other hand, when the upper surface of the heating plate 210 and the lower surface of the chuck plate 220 have flatness exceeding about 10 μm, respectively, between the heating plate 210 and the chuck plate 220 . Minor gaps may exist. Accordingly, the vacuum force may leak between the heating plate 210 and the chuck plate 220 .

The upper surface of the heating plate 210 and the lower surface of the chuck plate 220 each have a flatness of about 10 μm or less, preferably 7 μm or less. In this case, the heating plate 210 and the chuck plate 220 may be in close contact, and the vacuum force may be prevented from leaking through the space between the heating plate 210 and the chuck plate 220 .

The chuck plate 220 transfers heat generated by the heating plate 210 to the substrate 20 . In this case, the substrate 20 may be maintained at a temperature of about 140° C. to 150° C. to facilitate bonding of the chip (not shown) and the substrate 20 .

The heating plate 210 may be made of a ceramic material. An example of the ceramic material may be aluminum nitride (AlN). Since the aluminum nitride has high thermal conductivity, the heating plate 210 may uniformly transfer heat generated by the heating element 212 . Also, the heating plate 210 may uniformly heat the substrate 20 by making the temperature distribution of the chuck plate 220 uniform.

The chuck plate 220 may be formed by adding titanium to a ceramic material. For example, in the chuck plate 220 , titanium may be added to the aluminum oxide (Al ₂ O ₃ ). When titanium is added to the aluminum oxide (Al ₂ O ₃ ), the thermal conductivity of the chuck plate 220 may be further reduced.

When the titanium is added in an amount of less than about 10 parts by weight based on 100 parts by weight of the aluminum oxide in the chuck plate 220 , the increase in the porosity of the chuck plate 220 is insignificant and the thermal conductivity of the chuck plate 220 is pure. It may be similar to aluminum oxide.

When the amount of titanium exceeds about 20 parts by weight based on 100 parts by weight of the aluminum oxide in the chuck plate 220 , the porosity of the chuck plate 220 is excessively increased and thermal conductivity is greatly reduced. In addition, since the sintering density of the chuck plate 220 is reduced, the strength of the chuck plate 220 may be reduced, and vacuum force may be lost through the pores of the chuck plate 220 .

When about 10 to 20 parts by weight of the titanium is added based on 100 parts by weight of the aluminum oxide in the chuck plate 220, the chuck plate ( The porosity of 220 increases and the thermal conductivity of the chuck plate 220 also decreases. In this case, the sintered density of the chuck plate 220 may be about 3.5 to 3.7 g/cm 3 , which is slightly lower than the sintered density of pure aluminum oxide of about 3.9 g/cm 3 , so that the strength of the chuck plate 220 is not lowered. When the sintered density of the chuck plate 220 is less than about 3.5 g/cm 3 , the strength of the chuck plate 220 is low and there is a risk of damage. Since the chuck plate 220 is not pure aluminum oxide, it is difficult for the sintered density of the chuck plate 220 to exceed about 3.7 g/cm 3 .

Accordingly, the chuck plate 220 may be formed by adding about 10 to 20 parts by weight of titanium based on 100 parts by weight of the aluminum oxide.

When the thermal conductivity of the chuck plate 220 is less than about 5 W/m·k, the thermal conductivity of the chuck plate 220 is relatively low. Accordingly, the heat generated by the heating plate 210 may not be sufficiently transferred to the substrate 20 , or it may take a lot of time to transfer the heat generated from the heating plate 210 to the substrate 20 . . However, even if the bonding head thermocompresses the substrate 20 and the chip at a high temperature of about 450° C. for bonding the chip, rapid heating of the chuck plate 220 may be prevented.

When the thermal conductivity of the chuck plate 220 exceeds about 20 W/m·k, the thermal conductivity of the chuck plate 220 is relatively high. Accordingly, the heat generated by the heating plate 210 may be excessively transferred to the substrate 20 , so that the bump between the substrate 20 and the chip may be crushed. In addition, when the bonding head thermocompresses the substrate 20 and the chip at a high temperature of about 450° C., the chuck plate 220 is heated relatively rapidly so that a bump between the substrate 20 and the chip is formed. It can be crushed better.

When the thermal conductivity of the chuck plate 220 is about 5 to 20 W/m·k, the chuck plate 220 transmits heat generated from the thermal plate 210 to the substrate 20 so that the bumps are not crushed. It can be conveyed appropriately. In addition, even if the bonding head thermocompresses the substrate 20 and the chip at a high temperature of about 450° C. for bonding the chip, the chuck plate 220 may be prevented from being rapidly heated. Accordingly, it is possible to prevent the bump between the substrate 20 and the chip from being crushed.

Therefore, even if the substrate 20 is always preheated for bonding the substrate 20 and the chip, it is possible to prevent the pump between the substrate 20 and the chip from being crushed. Therefore, a bonding defect between the substrate 20 and the chip can be prevented.

Meanwhile, the chuck plate 220 may be made of only aluminum oxide (Al ₂ O ₃ ) having a lower thermal conductivity than the aluminum nitride.

The chuck plate 220 has a receiving groove 224 for receiving the alignment pin 216 . The receiving groove 224 may be formed at a position corresponding to the alignment pin 216 of the heating plate 210 . For example, the receiving groove 224 may also be disposed on the edge of the chuck plate 220 .

When the chuck plate 220 is seated on the upper surface of the heating plate 210 , the alignment pins 216 of the heating plate 210 may be inserted into the receiving groove 224 of the chuck plate 220 . have. Accordingly, the heating plate 210 and the chuck plate 220 may be accurately aligned.

Although it has been described in the above that the heating plate 210 is provided with an alignment pin 216 and the chuck plate 220 is provided with the receiving groove 224, the heating plate 210 is provided with the receiving groove, Alignment pins may be provided on the chuck plate 220 .

In addition, the chuck plate 220 has a groove 226 formed along an edge of the upper surface. The groove 226 may be used to seat the clamp 240 .

The guide ring 230 is caught in the groove 218 formed along the upper edge of the heating plate 210 and guides the circumference of the heating plate 210 .

Specifically, the guide ring 230 has a locking jaw 232 , and the guide ring 230 is mounted on the heating plate 210 as the locking jaw 232 is caught in the groove 218 .

Meanwhile, the upper surface of the guide ring 230 and the upper surface of the heating plate 210 may be positioned at the same height. In this case, the chuck plate 220 may be easily seated on the upper surface of the heating plate 210 while the guide ring 230 is mounted on the heating plate 210 .

In addition, when the upper surface of the guide ring 230 is positioned higher than the upper surface of the heating plate 210 , the guide ring 230 is seated on the upper surface of the heating plate 210 when the chuck plate 220 is seated on the upper surface of the heating plate 210 . ) can be used as a sorting criterion.

The clamp 240 is fixed to the guide ring while covering the edge of the upper surface of the chuck plate 220 . The clamp 240 may be fixed to the guide ring 230 by a fastening screw 242 .

For example, a plurality of clamps 240 may be provided to partially cover an edge of an upper surface of the chuck plate 220 . As another example, the clamp 240 may have a substantially ring shape and may entirely cover an edge of the upper surface of the chuck plate 220 .

Since the clamp 240 is fixed to the guide ring 230 while covering the upper surface edge of the chuck plate 220 , the clamp 240 may press the chuck plate 220 downward. Accordingly, the clamp 240 may attach the chuck plate 220 to the heating plate 210 .

The clamp 240 has a stopping protrusion 244 , and the stopping protrusion 244 may be placed in the groove 226 of the chuck plate 220 . Accordingly, the upper surface of the clamp 240 and the upper surface of the chuck plate 220 may be positioned at the same height. Therefore, when the substrate 20 is stably transferred to the upper surface of the chuck plate 220 without interference of the clamp 240 , it can be seated.

The guide ring 230 and the clamp 240 may be made of a material having a lower thermal conductivity than that of the heating plate 210 . For example, the guide ring 230 and the clamp 240 may be made of an aluminum oxide (Al ₂ O ₃ ) material. In addition, the guide ring 230 and the clamp 240 may be made of the same material as the chuck plate 220 .

Since the thermal conductivity of the guide ring 230 and the clamp 240 is lower than the thermal conductivity of the heating plate 210 , the guide ring 230 and the clamp 240 pass through the side surface of the heating plate 210 . Heat loss can be prevented.

The power cable 250 extends to the inside of the heating plate 210 and is connected to the heating element 212 , and provides power for the heating element 212 to generate heat.

The temperature sensor 260 extends from the outside to the inside of the heating plate 210 and measures the temperature of the heating plate 210 heated by the heating element 212 . The temperature of the heating element 212 may be controlled using the temperature measured by the temperature sensor 260 . The temperature of the heating plate 210 may be adjusted by controlling the temperature of the heating element 212 .

An example of the temperature sensor 260 may be a thermocouple.

The chuck structure 200 transfers heat generated by the heating plate 210 to the substrate 20 through the chuck plate 220 . The substrate 20 may be always heated to a constant temperature by the heat transferred by the chuck plate 220 . Accordingly, the chip 10 can be effectively bonded to the substrate 20 .

The bonding device 300 fixes the substrate 20 using the chuck structure 200 and rapidly heats and cools the chip 10 with the bonding head 100 in a state in which it is heated to a predetermined temperature. and bonding the chip 10 to the substrate 20 . Accordingly, it is possible to form solder of excellent quality and good shape between the chip 10 and the substrate 20 . In addition, the efficiency of a process of bonding the chip 10 to the substrate 20 using the bonding apparatus 300 may be improved.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the following claims. You will understand that you can.

Embodiments of the present invention may be applied to a bonding head provided to pick up a chip and bond it to a substrate, and a bonding apparatus including the bonding head. In the above, preferred embodiments of the present invention have been exemplarily described, but the scope of the present invention is not limited to such specific embodiments, and can be appropriately changed within the scope described in the claims.

Claims (21)

1. base block;

   an air block disposed on the base block; and

   A heating block disposed on the air block and provided to generate heat to heat the chip;

   The air block is a bonding head, characterized in that for cooling the heating block while suppressing the transfer of heat generated in the heating block to the base block by using air as a medium.
2. The bonding head according to claim 1, wherein the air block cools the heating block using an upward airflow in which the air rises from a lower portion of the air block toward a lower surface of the heating block.
3. According to claim 1, wherein the air block,

   a body disposed on the base block; and

   Columns extending upward from the body and supporting the heating block so that the heating block is spaced apart from the lower surface of the body;

   The body includes an inlet and an outlet,

   The inlet portion bonding head, characterized in that it comprises an inlet port and an inlet passage communicating with the inlet port.
4. 4. The bonding head according to claim 3, wherein the outlet portion includes an outlet and a discharge passage communicating the inlet and the outlet.
5. The bonding head according to claim 4, wherein a distance between the outlet and the lower surface of the heating block is in the range of 4 to 12 mm.
6. 5. The bonding head according to claim 4, wherein the discharge passage has a diameter of 5 to 15 mm.
7. The bonding head according to claim 4, wherein the diameter ratio of the inlet passage and the outlet passage is 1:1 to 1:1.5.
8. The bonding head according to claim 4, wherein the inlet and the outlet communicate in an “L” shape.
9. The bonding head according to claim 4, wherein the inlet and outlet are provided as at least one pair.
10. The bonding head according to claim 4, wherein the inlet portion and the outlet portion are provided in two or more pairs, and each pair is arranged at equal intervals.
11. The bonding head according to claim 3, wherein the body is made of SUS or Invar material.
12. 4. The method of claim 3, wherein each of the columns includes one of a vacuum line formed therein to transmit a vacuum force to a structure positioned above the heating block and a wiring line configured to transmit power to the heating block. bonding head with
13. According to claim 3, The air block,

    a connecting bar connecting the columns to each other; and

    The bonding head further comprises a flange extending in a radial direction from the connecting bar and guiding the flow of the air.
14. air block; and

    A heating block disposed on the air block and provided to generate heat to heat the chip;

    The air block is a bonding head, characterized in that for cooling the heating block at a cooling rate of 100 ℃ / sec or more while suppressing the transfer of heat generated in the heating block to the lower portion of the air block using air as a medium.
15. The bonding head according to claim 1, wherein the heating block includes a heating element built therein and generating heat by power applied from the outside.
16. The bonding head according to claim 1, wherein the heating block includes a heating element provided therein and a cover portion that is provided to surround the heating element as a whole, and made of aluminum nitride.
17. The bonding head according to claim 1, wherein the lower surface of the heating block has an exposed area larger than an unexposed area.
18. The bonding head according to claim 1, wherein the heating block has a surface roughness of 0.5 Ra or less and has a first side supporting the chip and a second side facing the first side and being blasted.
19. The method of claim 1, further comprising a suction plate provided on the heating block and provided to adsorb the chip,

    The heating block includes a first vacuum line and a second vacuum line that are formed to pass through each other in a vertical direction and provide a vacuum force to respectively adsorb the chip and the suction plate,

    wherein the suction plate includes a vacuum hole provided to communicate with the second vacuum line to provide a vacuum force to the chip.
20. The bonding head according to claim 1, wherein the heating block is made of a ceramic material, and the air block is made of a metal material.
21. a chuck structure supporting the substrate; and

    a bonding head provided to be movable above the chuck structure and bonding a chip to the substrate;

    The bonding head,

    base block;

    an air block disposed on the base block; and

    A heating block disposed on the air block and provided to generate heat to heat the chip;

    The air block is a bonding device, characterized in that it is provided to cool the heating block while suppressing the transfer of heat generated in the heating block to the base block using air as a medium.

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