KR102037948B1 - Die bonding method and apparatus - Google Patents

Abstract

In a die bonding method and apparatus, a plurality of dies are attached onto the substrate by a die attach module after the substrate to which the dies are to be attached is transferred to a die attach region. Subsequently, after transferring the substrate to the die bonding region, the dies attached to the substrate in the die bonding region are heated to a predetermined temperature and press the dies on the substrate by pressing a die at a predetermined pressure using a die bonding module. Bond to As described above, the pressure required for the die bonding process may be greatly shortened by simultaneously pressing and pressing the plurality of dies.

Description

Die bonding method and apparatus

Embodiments of the present invention relate to die bonding methods and apparatus. More particularly, the present invention relates to a method and apparatus for picking up dies from a wafer consisting of a plurality of dies and bonding the dies onto a substrate such as a leadframe or a printed circuit board.

In general, a die bonding process may be used to pick up dies from a wafer consisting of a plurality of dies on which semiconductor integrated circuits are formed and bond them onto a substrate such as a leadframe or a printed circuit board.

As an example, an apparatus for performing such a die bonding process is disclosed in Korean Patent Publication No. 10-2007-0037824. The die bonding apparatus may include a pickup module for picking up a die from the wafer and moving the die to a die stage, and a bonding module for picking up a die aligned on the die stage and bonding the die on the substrate.

The substrate may be transferred to a die bonding region by a substrate transfer module and heated to a preset temperature in the die bonding region. The die bonding module may bond the die on the substrate by pressing the die on the heated substrate for a predetermined time.

In particular, the time required for bonding the die when the bump pad provided on the substrate and the bump pad provided on the die are heated to a reflow temperature and pressurized to a predetermined pressing force to thermo-compress the die on the substrate. This may take several to tens of seconds. In addition, unlike the above, even when a die attach film (DAF) is provided on the back surface of the die, pressurization may be required for a sufficient time for sufficient compression of the die attach film.

As a result, the time taken to sequentially bond a plurality of dies using the bonding module on the substrate can be greatly increased, which can be a major factor in premise productivity degradation. In particular, in the case of a multi-chip package (MCP) in which a plurality of dies are stacked to form a single semiconductor package, stacking of a relatively large number of dies is required, which greatly increases the overall die bonding time. Can be.

SUMMARY Embodiments of the present invention provide a die bonding method and a die bonding apparatus which can greatly reduce the time required for bonding a plurality of dies onto a substrate.

A die bonding apparatus according to an aspect of the present invention for achieving the above object is to transfer a substrate to a die attach region, the step of attaching a plurality of die on the substrate in the die attach region, die die substrate And transferring the dies attached to the substrate in the die bonding region to heat the dies attached to the substrate to a predetermined temperature and press each die at a predetermined pressure to bond the dies onto the substrate.

According to another aspect of the present invention, a die bonding apparatus includes a wafer stage for supporting a wafer divided into a plurality of dies, a die attach module for attaching the dies onto a substrate in a die attach region; A die bonding module for bonding the dies onto the substrate by heating dies attached to the substrate to a predetermined temperature in a die bonding region and pressing each die at a predetermined pressure; and attaching the substrate to the die attach region and the substrate. And a substrate transfer module for transferring to the die bonding area.

According to embodiments of the invention, the die attach region may be provided with a first heat plate for heating the substrate, the die attach module is a die attach unit for picking up and attaching the dies on the substrate It may include.

According to embodiments of the present invention, the die bonding region may be provided with a second heat plate for heating the substrate, wherein the die bonding module is provided with a plurality of bonding heads for pressing the dies, respectively. It may include a unit.

According to embodiments of the present invention, the pressing unit may include a pressing plate with the bonding heads and a pressing head on which the pressing plate is mounted, and may be moved in a vertical direction by a pressing driver.

According to embodiments of the present invention, the pressurizing driver may pressurize the dies for a preset time through the pressurizing unit.

According to the embodiments of the present invention as described above, the plurality of dies may be pressed onto the substrate in the die attach region, and then heated to a predetermined temperature in the die bonding region and sufficiently thermocompressed at a predetermined pressure for a predetermined time. have. In particular, the bonding quality of the dies may be greatly improved by pressing the dies at predetermined pressures on the substrate using a plurality of bonding heads.

As a result, the time required for the bonding process for the dies may be reduced by simultaneously performing the bonding process for the plurality of dies, as compared with the conventional technique of performing the bonding process for the dies individually for each die. It can be greatly shortened.

1 is a flowchart illustrating a die bonding method according to an embodiment of the present invention.
FIG. 2 is a schematic diagram illustrating a die bonding apparatus suitable for performing the die bonding method illustrated in FIG. 1.
FIG. 3 is a schematic diagram illustrating the wafer stage and the die ejector illustrated in FIG. 2.
4 is a schematic diagram illustrating a die attach module and a die bonding module illustrated in FIG. 2.

Hereinafter, a head replacement apparatus and a die bonding system including the same according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing the drawings, similar reference numerals are used for similar elements. In the accompanying drawings, the dimensions of the structures are shown in an enlarged scale than actual for clarity of the invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

FIG. 1 is a flowchart illustrating a die bonding method according to an embodiment of the present invention, and FIG. 2 is a schematic diagram illustrating a die bonding apparatus suitable for performing the die bonding method illustrated in FIG. 1. FIG. 3 is a schematic diagram illustrating the wafer stage and the die ejector illustrated in FIG. 2, and FIG. 4 is a schematic diagram illustrating the die attach module and the die bonding module illustrated in FIG. 2.

1 to 4, the die bonding method and the die bonding apparatus 100 according to an embodiment of the present invention may include a plurality of dies 20 on a substrate 50 such as a lead frame or a printed circuit board. It can be preferably used for bonding.

The die bonding apparatus 100 includes a wafer stage 110 for supporting a wafer 10, a die attach module 140 for attaching the dies 20 to the substrate 50, and the substrate 50. It may include a die bonding module 160 for bonding the dies 20 attached to the substrate, a substrate transfer module 180 for transferring the substrate 50, and the like.

The wafer 10 may be provided in a divided state into a plurality of dies 20 through a dicing process. In particular, the wafer 10 may be attached to the dicing tape 30 in a completely cut or half cut state in the dicing process, and the dicing tape 30 is attached to the mounting frame 40 in the form of a circular ring. Can be mounted.

Although not shown, the die bonding apparatus 100 may include a load port for supporting the cassette 60 in which the wafers 10 are accommodated, and the wafer 10 may be formed through a separate wafer transfer mechanism. It may be moved onto the wafer stage 110.

The wafer stage 110 may be provided with a clamp 112 for holding the mounting frame 40, the dicing tape 30 is an expansion ring 114 provided on the wafer stage 110 Can be supported by. In particular, the expansion ring 114 may support an edge portion of the dicing tape 30, and the clamp 112 may lower the mounting frame 40 to expand the dicing tape 30. Can be moved.

Although not shown in detail, the wafer stage 110 may be provided with a clamp driver (not shown) for moving the clamp 112 in the vertical direction. The die may be extended by the dicing tape 30. The gap between the fields 20 can be secured sufficiently.

The lower part of the wafer stage 110 may be provided with a die ejector 120 for selectively raising the dies 20 to separate the dies 20 from the dicing tape 30, The die 20 lifted by the die ejector 120 may be picked up by the die transporter 125 and then transported. The wafer stage 110 may have an opening for the operation of the die ejector 120.

Although not shown in detail, the die transfer unit 125 may include a die pick-up unit for picking up the die 20 by vacuum suction and a driving unit for moving the die pick-up unit.

In addition, the die bonding apparatus 100 may include a die stage 130 on which the die 20 picked up by the die transfer unit 125 is placed. The die stage 130 may be used for alignment and appearance inspection of the die 20. For example, the die bonding apparatus 100 may include a separate image acquisition unit (not shown) for acquiring an image of the die 20 located on the die stage 125. Using the image, the alignment and appearance inspection of the die 20 can be performed. To this end, the die stage 130 may be configured to be rotatable, and may be configured to be movable in the vertical and horizontal directions for the transfer of the die 20.

Although the wafer stage 110, the die transfer unit 125, and the die stage 130 have been described as an example, the structure and arrangement of the components may be variously changed, and thus, the detailed structure of the components and The scope of the present invention will not be limited by the arrangement or the like.

The die attach module 140 may be used to pick up and attach the die 20 located on the die stage 130 onto the substrate 50. The die attach module 140 may include a die attach unit 142 for picking up and attaching the die 20 to the substrate 50. As an example, the die attaching unit 142 may include a collet for picking up the die 20 in direct contact with the die 20 by being provided under the die attaching head and the die attaching head. The die 20 may be picked up by a vacuum suction method. In addition, the die attach unit 142 may be moved by a separate driver. As an example, the die transfer unit 125 and the die attach module 140 may move the die 20 in the vertical and horizontal directions by a drive unit having a rectangular coordinate robot.

According to an embodiment of the present invention, the die attach module 140 may move the die 20 from the die stage 130 to the die attach region 150, wherein the die attach region 150 may be formed in the die attach region 150. A first heat plate 152 may be provided to heat the substrate 50 to a predetermined first temperature.

The first heat plate 152 may facilitate attachment of the die 20 by preheating the substrate 50. For example, the substrate 50 may be heated so that the bump pads provided on the substrate 50 and the bump pads provided on the die 20 may be pressed together. In particular, the first heat plate 152 may heat the substrate 50 to such an extent that binder materials included in the bump pads of the substrate 50 and / or the die 20 are bonded to each other. The attachment module 140 may press-fit the die 20 to the substrate 50 at a predetermined pressure. At this time, it is preferable that the bump pads of the substrate 50 and the die 20 are not electrically connected to each other.

As described above, the die attach module 140 may attach the die 20 to the substrate 50 within a relatively short time, and the plurality of dies 20 may be attached to the substrate 50. The die attach steps as described above may be repeatedly performed.

Meanwhile, the die bonding apparatus 100 may include a substrate transfer module 180 for transferring the substrate 50. The substrate transfer module 180 may include transfer rails 182 for supporting and guiding portions of both sides of the substrate 50, grippers 184 and grippers 184 for holding the substrate 50. A gripper transfer unit (not shown) for moving along the transfer rails 182 may be included. As an example, the distance between the transfer rails 182 may be configured to be adjustable according to the width of the substrate 50. Since the substrate transfer module 180 as described above is disclosed in detail in Korean Patent Application No. 10-2012-0138121 filed by the present applicant, further description thereof will be omitted.

On both sides of the substrate transfer module 180, the loader 192 in which the first magazine 190 containing the substrates 50 to be subjected to the die bonding process is disposed and the substrates 50 in which the die bonding process is completed are An unloader 197 in which the second magazine 195 to be stored may be disposed may be provided.

That is, the substrate transfer module 180 transfers the substrate 50 from the first magazine 190 to the second magazine 195 via the die attach region 150 and the die bonding region 170. Can be used to transfer.

The die bonding region 170 may be provided with a second heat plate 172 for heating the substrate 50 to a predetermined second temperature. The substrate transfer module 180 may move the substrate 50 to which the dies 20 are attached onto the second heat plate 172 of the die bonding region 170. The substrate 50 may be heated to the second temperature by 172.

For example, the second heat plate 172 may heat the substrate 50 above the reflow temperature of the bump pads of the substrate 50 and the die 20. In this case, the die bonding module 160 may sufficiently press the dies 20 on the substrate 50 by pressing the dies 20 to a predetermined pressure, whereby the substrate 50 ) And the bump pads of the die 20 may be electrically connected to each other. In particular, the die bonding module 160 may maintain a pressurized state with respect to the dies 20 for a predetermined time for sufficient thermal compression of the dies 20.

In addition, when an adhesive material or an underfill material is provided between the substrate 50 and the dies 20 as an example, the adhesive material or underfill material may be sufficiently cured by the heating and pressing.

The die bonding module 160 may include a pressing unit 162 provided with a plurality of bonding heads 164 to press each of the dies 20, and the pressing unit 162 may include a pressure driving unit. It can be moved in the vertical direction by 169.

The pressing unit 162 may include a pressing plate 165 with the bonding heads 164 and a pressing head 167 with the pressing plate 165 as shown in FIG. 4. Each of the bonding heads 164 may protrude from the lower surface of the pressing plate 165 to correspond to the size of the die 20.

In particular, the pressure plate 165 may be mounted to the pressure head 167 to be replaced. This is to counteract when the size of the dies 20 bonded on the substrate 50 is changed. As an example, the pressure plate 165 may be mounted to the pressure head 167 using a magnetic force by the permanent magnet 168. In this case, the pressing head 167 may be provided with a permanent magnet 168 as shown, the pressing plate 165 may be made of a magnetic material.

Meanwhile, the pressure driving unit 169 may press the dies 20 at a predetermined pressure as described above, and in particular, the pressure applied to the dies 20 may be constant during the time. Can be controlled. For example, the pressure driving unit 169 may be configured using an air bearing, an air sonic module, a voice coil motor (VCM), etc. in order to constantly control the pressure.

Hereinafter, a die bonding method according to an embodiment of the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 1, first, the substrate 50 is transferred to the die attaching region 150 in step S100, and the plurality of dies 20 are placed on the substrate 50 positioned in the die attaching region 150 in step S102. Attach. For example, the substrate 50 is mounted on the first heat plate 152 of the die attach region 150 from the first magazine 190 by the substrate transfer module 180 on the transfer rails 182. It may be moved to, and may be preheated to a first temperature by the first heat plate 152.

Meanwhile, the die transfer unit 125 picks up the die 20 from the wafer 10 and moves the die 20 onto the die stage 130, and the die attach module 140 moves the die (from the die stage 130). 20 may be picked up and attached to the substrate 50. The step S102 may be repeatedly performed until all of the dies 20 are attached to the substrate 50.

In addition, unlike the above, the die attach module 140 may pick up the die 20 from the wafer 10 and then attach the die 20 onto the substrate 50. The attachment module 140 may pick up the die 20 from the wafer 10 and then put down the picked up die 20 on the die stage 130. After inspection and / or alignment of the die 20 is completed, the die 20 on the die stage 130 may be attached onto the substrate 50.

In operation S104, the substrate 50 is transferred to the die bonding region 170. The substrate 50 may be transferred from the first heat plate 152 of the die attaching region 150 onto the second heat plate 172 of the die bonding region 170 by the substrate transfer module 180. Can be.

Subsequently, in operation S106, the dies 20 attached to the substrate 50 are heated to a preset second temperature and pressurized to a predetermined pressure, respectively, to thereby press the dies 20 onto the substrate 50. Heat-compress sufficiently. In detail, the substrate 50 may be heated to the second temperature by the second heat plate 172, and the dies 20 may be heated at a predetermined pressure by the die bonding module 160. It can be sufficiently pressurized for a set time.

As described above, the substrate 50 having the die bonding process completed may be accommodated in the second magazine 195 by the substrate transfer module 180.

According to the embodiments of the present invention as described above, the plurality of dies 20 are pressed onto the substrate 50 in the die attach region 150 and then heated to a predetermined temperature in the die bonding region 170. And sufficient thermal compression at a predetermined pressure for a predetermined time. In particular, the bonding quality of the dies 20 may be greatly improved by pressing the dies 20 at predetermined pressures on the substrate 50 using the plurality of bonding heads 164.

While the foregoing has been described with reference to preferred embodiments of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

10 wafer 20 die
30: dicing tape 40: mounting frame
50: substrate 60: cassette
100: substrate supply apparatus 110: wafer stage
120: die ejector 125: die transfer unit
130: die stage 140: die attach module
150: die attach region 152: first heat plate
160: die bonding module 162: pressurization unit
164: bonding head 165: pressure plate
167: pressure head 169: pressure drive unit
170: die bonding area 172: second heat plate
180: substrate transfer module 182: transfer rail
184: Gripper

Claims (6)

delete A wafer stage for supporting a wafer divided into a plurality of dies;
A die attach module for attaching the dies on the substrate in a die attach region;
A die bonding module for bonding the dies on the substrate by heating dies attached to the substrate to a predetermined temperature in a die bonding region and pressing each die at a predetermined pressure; And
A substrate transfer module for transferring the substrate to the die attach region and the die bonding region,
The die bonding module includes a pressing unit having a plurality of bonding heads for pressing the dies respectively, the pressing unit including a pressing plate having the bonding heads and a pressing head on which the pressing plate is mounted. The pressing head is a permanent magnet is built-in, the pressing plate is a die bonding apparatus, characterized in that mounted to the pressing head by the magnetic force of the permanent magnet. 3. The die attach region of claim 2, wherein the die attach region is provided with a first heat plate for heating the substrate, and the die attach module includes a die attach unit for picking up and attaching the dies to the substrate. Die bonding apparatus. The die bonding apparatus of claim 2, wherein a second heat plate for heating the substrate is provided in the die bonding region. 5. The die bonding apparatus according to claim 4, wherein the pressing unit is moved in the vertical direction by the pressing driver. The die bonding apparatus of claim 5, wherein the pressure driving unit presses the dies for a predetermined time through the pressing unit.

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