KR20080070217A - Method for flip chip bonding - Google Patents

Abstract

A method for bonding a flip chip is provided to improve the productivity and the joining reliability by quickly heating the flip chip and a bump using a laser beam. A method for bonding a flip chip comprises the steps of: arranging a semiconductor chip(110) and a substrate(120); correcting an irradiation position of laser according to the irradiation position of laser with the arranged semiconductor chip and the substrate; generating a laser beam(L) from a laser light source; irradiating the laser beam to an upper surface of the semiconductor chip; and joining a junction of the semiconductor chip and the substrate. Consequently, the productivity and the joining reliability are increased by applying a laser pressing method.

Description

Flip chip bonding method

1 is a block diagram showing a schematic configuration of a bonding apparatus for performing a conventional laser crimping method.

2 is a block diagram showing a configuration of a flip chip bonding apparatus according to an embodiment of the present invention.

3 is a perspective view illustrating a relationship between heating mechanisms of the semiconductor chip of FIG. 2.

4 is a diagram illustrating a change in irradiation center according to rotation of the first and second scan mirrors included in the flip chip bonding apparatus of FIG. 3.

5 is a flowchart illustrating a flip chip bonding method in another aspect of the present invention.

FIG. 6 is a detailed flowchart illustrating step S10 of FIG. 5.

FIG. 7 is a flowchart illustrating the operation (S20) of FIG. 5 in detail.

FIG. 8 is a detailed flowchart illustrating step S40 of FIG. 5.

9A to 9C are diagrams illustrating each step of performing the flip chip bonding method of FIG. 5.

10A to 10D are diagrams illustrating each step of performing step S20 of FIG. 6.

<Explanation of symbols for main parts of drawing>

100: flip chip bonding device 110: semiconductor chip

115: conductive bump 120: substrate

130: bonding head 132: pickup flow path

140: bonding stage 150: semiconductor chip heating mechanism

152: laser light source 154: focusing lens

155a: first scan mirror 155b: second scan mirror

156: lens for uniform line speed 162: laser drive unit

165: scan mirror driver L: laser beam

The present invention relates to a flip chip bonding method, and more particularly, to a flip chip bonding method in which the laser beam is irradiated at an accurate position by adjusting the beam width and the irradiation direction of the laser beam.

Recently, as electronic products have been miniaturized and highly functionalized, semiconductor chips, which form a core part of electronic products, have also become highly integrated and high performance. In the manufacture of semiconductor packages that protect these highly integrated and high-performance semiconductor chips from dust, moisture, or various external environments such as electrical and mechanical loads, the trend toward thin and short and multi-pinning is strengthened. have.

Therefore, the semiconductor package method is also difficult to cope with the trend of thin and short and multi-pin with the existing wire bonding method, and a variety of new ways to solve this problem are being sought. The method is a solder bump method.

In the solder bump method, a separate solder bump is formed on a pad, which is an input / output terminal of a semiconductor chip, and then the semiconductor chip is inverted and directly attached to a circuit pattern of a carrier substrate or a circuit tape. In this way, it is referred to as 'flip chip bonding' because the semiconductor chip is bonded upside down.

Conventional flip chip bonding methods are largely classified into a thermocompression method and a laser compression method. In the case of the thermocompression bonding system as shown in Japanese Patent Laid-Open No. 2002-141376, the semiconductor chip must be heated for a long time due to the high heat loss at the heat transfer site that appears when the semiconductor chip is heated. This long time heating results in a decrease in productivity as well as a long time to reach the junction temperature of the solder bumps, there is a problem that can not be applied to a material sensitive to high temperatures. In addition, the thermal compression method not only causes a problem of bonding accuracy in which the bonding position is slightly shifted due to the difference in thermal expansion coefficient between the semiconductor chip and the substrate, but also cracks in the slightly twisted portion due to shrinkage of the semiconductor chip and the substrate after cooling. There is a problem that damage such as a joint occurs.

The laser pressing method is a method in which solder bumps of a semiconductor chip are moved to a bond position to face a designated solder bump of a substrate, and then pressurized while heating the semiconductor chip from a rear surface of the semiconductor chip, and the semiconductor chip is heated using a laser. Because of the heating using such a laser there is an advantage that high productivity and low thermal expansion coefficient can be obtained in a short time.

FIG. 1 is a block diagram showing a schematic configuration of a bonding apparatus 10 performing a conventional laser crimping method disclosed in US Pat. No. 5,500,502. Referring to FIG. 1, a semiconductor chip 1A having a bump 2A is seated on a pedestal 1, and a lead frame having a plurality of lead terminals 9 is disposed above the semiconductor chip 1A. It is. The laser beam 11 emitted from the laser irradiation means 3 is focused on the lead terminal 9 while passing through the shutter 25, the reflected light 5, and the condenser lens 7, so that the lead terminal 9 and the semiconductor chip 1A ) Is heated, and the lead terminal 9 and the semiconductor chip 1A thus heated by the laser beam are bonded to each other.

While the lead terminal 9 and the semiconductor chip 1A are heated, the temperature sensor 13 receives an infrared ray emitted from the lead terminal to generate an electrical signal. The electrical signal from the temperature sensor 13 is amplified by the amplifier 15 and then filtered by the filter circuit 17 to filter the high frequency components, and then digitally converted by the A / D converter 19 and then the computer 21. ) Is entered. The computer 21 determines the contact state between the lead terminal 9 and the bump 2A based on the input signal from the A / D converter 19, and the determination result is displayed on the display device 23 at the same time. After determining the bonding state of the computer 21, the shutter 3 of the laser is opened and closed.

However, in the conventional laser compression method, since the laser beam is focused by the condenser lens 7, bonding is possible only in a limited area. Therefore, the light energy of the region to which the laser beam is irradiated becomes nonuniform. The intensity distribution of the focused laser generally has a Gaussian profile so that the amount of light at the center of the light is high and the amount of light at the periphery is low. Therefore, when the laser light is irradiated based on the amount of light in the center during bonding, the amount of light in the peripheral part is insufficient, and when the laser light is irradiated in the peripheral part, the light amount in the center part is excessively high.

That is, since the laser beam width cannot be adjusted, the laser beam is not evenly irradiated on the upper surface of the semiconductor chip 9. When the laser beam 11 is not evenly irradiated on the upper surface of the semiconductor chip 9, it is impossible to evenly heat all the bumps 2A disposed on the semiconductor chip, resulting in uneven distribution of energy on one semiconductor chip 9. The problem that arises arises. This problem leads to problems such as distortion due to thermal deformation of the semiconductor chip 9, weakening of the bonding strength in the part that is not sufficiently heated during the bump, and increase of the heating time. It is emerging. In particular, when the size of the semiconductor chip 1A mounted on the substrate by the flip chip bonding apparatus is changed in various ways, it becomes more problematic.

In addition, in order to bond with respect to the whole area | region of the semiconductor chip 1A, bonding should be performed, moving the pedestal 1 precisely so that a laser beam may be irradiated to the position where bump 2A exists. However, as the size of the semiconductor chip 1A increases, the stroke of the pedestal 1 on which the semiconductor chip 1A is seated must increase. As a result, it is difficult to accurately drive the pedestal 1 and there is a problem that the size of the pedestal 1 is increased.

In addition, in order for the laser to be irradiated to the entire area of the semiconductor chip 1A accurately, the bonding position of the semiconductor chip and the substrate must be coincident, and the laser irradiation position should be exactly matched with the laser irradiation axis origin. However, in the conventional flip chip bonding method as described above, there is no separate process for matching the laser irradiation position and the semiconductor chip. Therefore, the laser irradiation position and the semiconductor chip may be inconsistent. In this case, the laser may not irradiate the upper surface of the semiconductor chip, and thus, the solid bonding of the semiconductor chip may not be performed. In addition, the laser may be irradiated to the substrate may cause a problem that the substrate is damaged.

The present invention is to solve the above problems, an object of the present invention is to provide a flip chip bonding method that can obtain a high productivity and bonding reliability by applying a laser compression method.

The present invention comprises the steps of aligning the semiconductor chip and the substrate; Correcting the irradiation position of the laser so that the aligned semiconductor chip and the substrate and the irradiation position of the laser coincide with each other; Generating a laser beam from a laser light source; Irradiating the laser beam on an upper surface of the semiconductor chip; And heating and bonding a bonding portion of the semiconductor chip and the substrate.

In the present disclosure, the step of aligning the semiconductor chip and the substrate may include calculating a center coordinate and an angle of the substrate; Calculating a center coordinate and an angle of the semiconductor chip; And moving the semiconductor chip to a bonding position on the substrate by a difference of the calculated respective values.

In the present invention, the step of correcting the irradiation position of the laser to match the irradiation position of the aligned semiconductor chip and the substrate and the laser, calculating the distance between the semiconductor chip and the initial laser irradiation position; Calculating a slope between the semiconductor chip and the initial laser irradiation position; And rotating the scan mirror to correct the laser irradiation position by the calculated distance and inclination.

In one embodiment, the scan mirror comprises: a first scan mirror rotating about a first axis such that an angle at which the laser beam from the laser light source is refracted is continuously changed; Rotation about the second axis different from the first axis such that the angle at which the laser beam from the first scan mirror is refracted is continuously changed so that the irradiation center position of the laser beam is continuously changed on the upper surface of the semiconductor chip. It may include a second scan mirror.

In the present invention, the initial laser irradiation position may be formed around the laser optical axis origin of the bonding head.

In the present invention, the step of irradiating the laser beam on the upper surface of the semiconductor chip, two scan mirrors disposed in the optical path between the laser light source and the semiconductor chip can be made by continuously changing the refractive direction of the laser beam. have.

In the present invention, the irradiating the laser beam on the upper surface of the semiconductor chip may further include refracting the laser beam such that the laser beam passing through the scan mirror is irradiated on the upper surface of the semiconductor chip at the same line speed. Can be.

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

2 is a block diagram showing the configuration of a flip chip bonding apparatus 100 according to an embodiment of the present invention. As shown in FIG. 2, the flip chip bonding apparatus 100 according to an embodiment of the present invention includes a bonding stage 140, a bonding head 130, and a semiconductor chip heating mechanism 150. In this case, the semiconductor chip heating mechanism 150 includes a laser light source 152, a first scan mirror 155a, and a second scan mirror 155b.

The bonding stage 140 sequentially seats the substrate 120 transferred by a transfer means (not shown). In this case, although not shown, the bonding stage 140 has a plurality of adsorption flow passages penetrating to the upper surface in parallel, it can be fixed so as not to move the substrate 120 by using the adsorption force generated through the adsorption flow path. have. In addition, the bonding stage 140 may be provided with a heater. The heater preheats the substrate 120 fixed to the upper surface to a predetermined temperature to shorten the tact time.

The bonding head 130 moves up and down on the bonding stage 140. The bonding head 130 compresses the semiconductor chip 110 in a flip chip shape on the substrate 120 seated on the bonding stage 140. As an example of the bonding head 130, a pickup flow passage 132 is formed inside the bonding head 130 to pick up the semiconductor chip 110, and supplies negative pressure air through the pickup flow passage 132. The semiconductor chip 110 is picked up, and the semiconductor chip 110 is pressed onto the substrate 120 by removing the negative pressure air or supplying the positive pressure air through the pickup flow path 132.

A conductive bump 115 is formed on a lower surface of the semiconductor chip 110, more specifically, a lower surface of the electrode of the semiconductor chip 110. The conductive bump 115 includes an electrode of the semiconductor chip 110 and a substrate 120. It is fused between the terminals formed at the to mediate the coupling between the two.

On the other hand, the semiconductor chip heating mechanism 150 includes a laser light source 152, a first scan mirror 155a, and a second scan mirror 155b.

Here, the first scan mirror 155a is rotated about the first axis and refracts the laser beam L emitted from the laser light source 152. In this case, the angle at which the laser beam L is refracted is continuously changed by the rotation of the first scan mirror 155a.

The second scan mirror 155b is rotated about a second axis different from the first axis, and irradiates the laser beam L emitted from the first scan mirror 155a onto the upper surface of the semiconductor chip 110. In this case, the laser beam L emitted from the first scan mirror 155a continuously changes the angle of refraction toward the upper surface of the semiconductor chip 110 as the second scan mirror 155b rotates. The irradiation center position of the laser beam L is continuously changed on the upper surface of the semiconductor chip 110.

When using one scan mirror, one direction, that is, one-dimensional scan, is possible. Therefore, when the size of the semiconductor chip 110 is large, it is not possible to scan uniformly as a whole. However, when the first scan mirror 155a and the second scan mirror 155b are used, two-dimensional scanning is possible, so that each portion of the upper surface of the semiconductor chip 110 can be scanned. Meanwhile, as shown in FIG. 3, at least one diffusion mirror 153 for diffusing the laser beam L may be further provided.

In this case, it is preferable that the first axis that is the rotation axis of the first scan mirror 155a and the second axis that is the rotation axis of the second scan mirror 155b form a right angle with each other. That is, as shown in FIG. 4, the first scan mirror 155a is rotated about the X axis as the X axis, and the laser beam L is irradiated in the Y axis direction. As the Y axis, the second scan mirror 155b may rotate about the Y axis so that the laser beam L is irradiated in the X axis direction. As a result, the laser beam L may scan while moving freely in the X-axis and Y-axis directions of the upper surface of the semiconductor chip 110, so that the laser beam L may be uniformly scanned on the upper surface of the semiconductor regardless of the size of the semiconductor chip 110. In particular, when the laser beam L is repeatedly scanned at high speed, the laser beam L irradiated on the upper surface of the semiconductor chip 110 may be uniformed by a time average effect.

2, the semiconductor chip heating mechanism 150 may further include a focusing lens 154. The focusing lens 154 is formed in an optical path between the laser light source 152 and the first scan mirror 155a to control the size of the laser beam L at the bonding position.

The focusing lens 154 may be a cylindrical lens installed to adjust the width of the incident laser beam, and may be configured to adjust the light beam width of the laser beam L in one direction. Therefore, even when the size of the semiconductor chip 110 is changed, the focusing lens 154 makes the width of the laser beam L equal to the width of the upper surface of the semiconductor chip 110, and the length of the size of the semiconductor chip 110. The direction is determined by the scan angles of the scan mirrors 155a and 155b, so that the laser beam L can be efficiently scanned.

In addition, when the size of the semiconductor chip 110 is changed, the offset value according to the alignment result of the semiconductor chip 110 and the bonded substrate 120 may be corrected. That is, since the stroke of the bonding stage 140 does not need to be changed as in the related art, the bonding stage 140 can be precisely controlled to drive.

In addition, a line speed uniform lens 156 may be disposed in the optical path between the scan mirrors 155a and 155b and the semiconductor chip 110. The linear velocity uniform lens 156 is disposed in an optical path between the second scan mirror 155b and the semiconductor chip 110, and the laser beam L is at the same angle to the upper surface of the semiconductor chip 110. It serves to refract the laser beam (L) to be irradiated with. That is, the laser beam L scanned through the scan mirrors 155a and 155b performs angular motion, and thus the linear velocity projected onto the semiconductor chip 110 is not constant. In this case, since the amount of light scanned on the semiconductor chip 110 is proportional to the linear velocity, if the laser beam L is irradiated onto the semiconductor chip 110 at the same angular velocity, the linear velocity of the laser beam L is changed, and as a result, As a result, the amount of light scanned on the surface of the semiconductor chip 110 is different for each position. In order to prevent this, the linear velocity uniform lens 156 may be disposed behind the scan mirror so that the linear velocity of the laser beam L on the surface of the semiconductor chip 110 is constant, thereby reducing the unevenness of light. It can be controlled effectively. In this case, at least the linear velocity uniform lens 156 may be disposed on the pickup flow path 132 formed inside the bonding head 130.

Meanwhile, the present invention may include an optical fiber 157 forming an optical path of the laser beam L from at least the laser light source 152 to the focusing lens 154. Alternatively, an optical fiber may be formed from the laser light source 152 to the first scan mirror 155a.

Meanwhile, the present invention may further include a scan mirror driver 165 and a laser driver 162. The scan mirror driver 165 drives the first and second scan mirrors, and the laser driver 162 drives the laser light source 152. That is, the scan mirror driver 165 drives the scan mirrors 155a and 155b so that the laser beam L irradiated onto the semiconductor chip 110 is scanned with the same size as the semiconductor chip 110, and the laser driver ( The 162 drives the laser light source 152 with the required power by the time required for the laser beam L. The scan mirror driver 165 and the laser driver 162 may be controlled by the driving controller 160.

In this case, it is preferable that the laser beam L used is an infrared ray having a wavelength that can pass through the semiconductor chip 110. The laser beam L is formed of silicon (Si) so as to pass through the semiconductor chip 110. A laser diode having a special wavelength of about 1064 nm and having a wavelength close to red can be selected. That is, the laser beam L is irradiated on the opposite side of the surface on which the conductive bumps 115 are formed in the semiconductor chip 110 so that the energy of the laser heats the semiconductor chip 110 and the conductive bumps 115. In addition, the flip chip bonding method of the laser crimping method uses the laser beam L when connecting the conductive bumps 115 formed on both sides of the semiconductor chip 110 or the connection pad of the substrate 120 as well as on both sides. The semiconductor chip 110 and the conductive bumps 115 may be heated.

Meanwhile, as shown in FIG. 2, in the flip chip bonding apparatus 100 according to the exemplary embodiment of the present invention, at least one reflective lens 158 may be disposed to refract the laser beam in a desired direction.

5, 6, and 8 are flowcharts illustrating a flip chip bonding method according to another exemplary embodiment of the present invention. In addition, each step of the flip chip bonding method is illustrated in FIGS. 9A to 9C. 10A to 10D illustrate a step S10 of aligning a semiconductor chip and a substrate in the flip chip bonding method.

Referring to FIG. 5, the flip chip bonding method includes aligning a semiconductor chip and a substrate (S10), and correcting an irradiation position of a laser so that the irradiation positions of the aligned semiconductor chip and the substrate match the laser (S20). And emitting a laser beam from a laser light source (S30), irradiating the laser beam to the upper surface of the semiconductor chip such that the irradiation center position of the laser beam is continuously changed on the upper surface of the semiconductor chip (S40), And bonding the semiconductor chip and the substrate while heating the semiconductor chip (S50).

Hereinafter, each step of the flip chip bonding method will be described in detail with reference to FIGS. 5 to 8, 9A to 9C, and 10A to 10D.

First, referring to FIGS. 6 and 9A, an operation S10 of aligning a semiconductor chip and a substrate is performed.

In detail, as shown in FIG. 9A, the substrate 120 is disposed on the bonding stage 140 heated to a set temperature. In this case, position information may be obtained using an alignment mark formed on the substrate 120 in a vision system (not shown) (S11).

The semiconductor chip 110 is vacuum-adsorbed to the bottom surface of the bonding head 130 through the pickup flow passage 132 inside the bonding head 130. Also in this case, the alignment mark formed on the semiconductor chip 110 may be recognized by a vision system (not shown) to obtain position information of the semiconductor chip 110 (S12).

Then, by using the measured position information of the substrate 120 and the semiconductor chip 110, the bonding head 130 that has adsorbed the semiconductor chip 120 is moved to a place corresponding to the bonding position of the substrate 120 ( S13). In detail, FIG. 10A illustrates a state before the correction between the substrate 120 and the semiconductor chip 110 is performed, and FIG. 10B illustrates a correction between the substrate 120 and the semiconductor chip 110. It is a figure which shows the state in which the bonding position 121 on 120 and the semiconductor chip 110 adsorb | sucked by the bonding head 130 are arrange | positioned so that it may correspond. That is, a relative position offset between the substrate 120 and the semiconductor chip 110 is calculated from the measured position information of the substrate 120 and the semiconductor chip 110. Then, the bonding head 130 moves in parallel in the XY direction by the calculated value, and the bonding head 130 rotates relative to the laser optical axis origin 135 to bond the substrate 120 as shown in FIG. 10B. Position 121 and semiconductor chip 110 are arranged to coincide. After the correction is made as described above, the bonding head 130 is lowered to contact the conductive bumps 115 of the semiconductor chip 110 on the electrodes 125 of the substrate 120.

Next, referring to FIGS. 7, 9A, and 10A to 10D, a step (S20) of correcting the irradiation position of the laser is performed so that the aligned semiconductor chip and the substrate and the irradiation position of the laser coincide.

If the laser irradiation position 137 is irradiated only in the form of the semiconductor chip 110 based on the laser optical axis origin 135 without correcting the laser irradiation position 137, the semiconductor chip 110 may not be irradiated with the upper surface of the semiconductor chip 110. The substrate 120 may be damaged without being bonded. Further, when the laser is irradiated with the coordinates of the first semiconductor chip 110, the laser does not irradiate at the correct position because the XY offset of the semiconductor chip 110 coincides but the rotation angles do not coincide.

Therefore, in order to irradiate the laser evenly over the entire bonding position 121 of the actual semiconductor chip 110 and the substrate, the laser irradiation position 137 should be corrected by rotating the scan mirrors 155a and 155b.

That is, as shown in FIGS. 10B and 10C, the distance between the semiconductor chip 110 and the initial position of the laser irradiation position 137 so that the laser optical axis origin 135 coincides with the center of the semiconductor chip 110. (S21) Here, the initial laser irradiation position is formed around the laser optical axis origin of the bonding head.

10C and 10D, the inclination between the longitudinal extension line of the semiconductor chip and the extension line in the longitudinal direction of the initial laser irradiation position such that the laser irradiation position 137 and the semiconductor chip 110 coincide with each other. Is calculated. (S22)

In addition, the parallel and rotational movements of the laser irradiation position are performed by the scan mirror driver 165 rotating the scan mirrors 155a and 155b at an appropriate angle according to the control of the drive controller 160 (S23). By rotating the two scan mirrors 155a and 155b mutually, the laser irradiation position 137 is moved in parallel in the XY direction (that is, the arrow direction in FIG. 10B), and also about the laser optical axis origin 135. The laser irradiation position 137 is rotated.

By such a configuration, the bonding position 121 of the substrate 120 and the semiconductor chip 110 coincide with each other, and the laser irradiation position 137 coincides with the bonding position 121 and the semiconductor chip 110. do. Therefore, by irradiating the laser at the correct position, it is possible to obtain the effect that firm bonding is performed and damage to the substrate is prevented.

In this state, as shown in FIG. 9B, the step S30 of irradiating the laser beam L from the laser light source 152 to the outside and the laser beam L irradiated from the laser light source 152 are irradiated. Irradiating the upper surface of the semiconductor chip 110 so that the center position is continuously changed from the upper surface of the semiconductor chip 110 (S40).

In this case, referring to FIG. 3 along with FIG. 9B, the laser beam L from the laser light source 152 may be guided by the optical fiber and pass through the focusing lens 154, and pass through the focusing lens 154. While the size of the laser beam (L) is determined (S41).

The laser beam L passing through the focusing lens 154 is irradiated onto the upper surface of the semiconductor chip 110 while passing through the scan mirrors 155a and 155b. At this time, the scan mirrors 155a and 155b rotate about one axis, and the scan mirrors 155a and 155b rotate on the upper surface of the semiconductor chip 110 of the laser beam L as the scan mirrors 155a and 155b rotate. The irradiation center is continuously changed (S42).

In this case, the laser beam L passing through the focusing lens 154 may be continuously irradiated to the upper surface of the semiconductor chip 110 while continuously moving in two directions. For this purpose, as illustrated in FIG. Two can be arranged. That is, as shown in FIG. 2, the laser beam L passing through the focusing lens 154 scans continuously in the Y-axis direction while passing through the first scan mirror 155a, and the first scan mirror 155a. The laser beam L is continuously scanned in the X-axis direction while passing through.

On the other hand, since the size of the semiconductor chip 110 is already set in the drive controller 160 at the time of alignment mark recognition, the scan mirror driver 165 performs the scan mirrors 155a and 155b under the control of the drive controller 160. ) To the proper angle. In addition, the driving controller 160 controls the laser driver 162 to generate the laser beam L with the required power for the required time.

On the other hand, the laser beam L refracted by the scan mirrors 155a and 155b has a uniform linear velocity toward the upper surface of the semiconductor chip 110 by the linear velocity uniform lens 156 (S43). At a uniform line speed, the laser beam L is continuously scanned while varying the center of irradiation on the upper surface of the semiconductor chip 110 (S44). At this time, if the laser beam L is repeatedly scanned at a high speed, the amount of laser light irradiated onto the semiconductor chip 110 may be made uniform by a time average effect.

In this state, the laser beam L is transmitted to the semiconductor chip 110 and converted into thermal energy in the conductive bump 115 on the semiconductor chip 110 and the substrate 120, and the semiconductor chip 110 and the substrate ( The output of the laser beam L heats the conductive bumps 115 while the conductive bumps 115 installed in the 120 are in contact with each other. In addition, since the bonding head 130 applies a constant pressure in the vertical direction to the semiconductor chip 110, the conductive bumps 115 are heated and pressurized by the laser beam L to bond the substrate 120 to the electrodes ( S50).

Then, as shown in FIG. 9C, when the irradiation of the laser beam L through the bonding head 130 stops the cooling of the conductive bumps 115, the temperature of the semiconductor chip 110 is lowered and thereby the conductive bumps. When the 115 is solidified, the suction vacuum of the semiconductor chip 110 is released and the bonding head 130 is raised to complete flip chip bonding.

Meanwhile, the substrate and the semiconductor chip may be flip chip bonded using a thermosetting resin (not shown) applied on the substrate 120. In this case, when the thermal bonding between the semiconductor chip 110 and the terminal portions of the substrate 120 occurs and successively the thermosetting resin is cured at the same time by the heating of the semiconductor chip 110 and the substrate 120 at the same time in the adhesive surface outside It is more effective because there is no need for a separate step for sealing the gap between the semiconductor chip 110 and the substrate 120 to prevent the corrosion effect.

As described above, according to the flip chip bonding method of the present invention and the flip chip bonding apparatus employing the same, high productivity and bonding even when a relatively temperature sensitive substrate is used because the flip chip and the bump can be heated quickly using a laser. It is effective to obtain reliability.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (7)

Aligning the semiconductor chip with the substrate; Correcting the irradiation position of the laser so that the aligned semiconductor chip and the substrate and the irradiation position of the laser coincide with each other; Generating a laser beam from a laser light source; Irradiating the laser beam on an upper surface of the semiconductor chip; And And bonding the semiconductor chip and the bonding portion of the substrate while heating. The method of claim 1, Aligning the semiconductor chip and the substrate, Calculating a center coordinate and an angle of the substrate; Calculating a center coordinate and an angle of the semiconductor chip; And And moving the semiconductor chip to a bonding position on the substrate by a difference of the calculated respective values. The method of claim 1, Correcting the irradiation position of the laser to match the irradiation position of the laser and the aligned semiconductor chip, the substrate, Calculating a distance between the semiconductor chip and the initial laser irradiation position; Calculating a slope between the semiconductor chip and the initial laser irradiation position; and And rotating the scan mirror such that the laser irradiation position is corrected by the calculated distance and inclination. The method of claim 3, wherein The scan mirror, A first scan mirror rotating about a first axis such that an angle at which the laser beam from the laser light source is refracted is continuously changed; Rotation about the second axis different from the first axis such that the angle at which the laser beam from the first scan mirror is refracted is continuously changed so that the irradiation center position of the laser beam is continuously changed on the upper surface of the semiconductor chip. Flip chip bonding method comprising a second scan mirror. The method of claim 3, wherein And the initial laser irradiation position is formed around the laser optical axis origin of the bonding head. The method of claim 1, Irradiating the laser beam on the upper surface of the semiconductor chip, And two scan mirrors arranged in an optical path between the laser light source and the semiconductor chip by continuously changing the refraction direction of the laser beam. The method of claim 6, Irradiating the laser beam on the upper surface of the semiconductor chip, And refracting the laser beam such that the laser beam passing through the scan mirror is irradiated onto the semiconductor chip at the same line speed.

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