JP2010123786A - Bonding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To bond an electronic component in an inert gas atmosphere even to a substrate which is large-sized and has many bonding positions with a small opening for insertion of a bonding head of a coating means by enabling the position of the opening to be changed. <P>SOLUTION: The bonding device employs following means. Firstly, the bonding device includes a bonding head 3, a bonding stage 6, the substrate coating means 8, 9 on the stage, and an inert gas supply means for supplying inert gas into them, and bonds the electronic component 1 to the different positions of the one substrate a plurality of times in the inert gas atmosphere. Secondary, the coating means include an outer peripheral member enclosing the substrate, an upper member covering the top of the substrate and also having an opening into which the tip of the bonding head is inserted, and a coupling means for bringing both into contact with each other. Thirdly, the contact state is canceled to move the upper member relatively to the outer peripheral member, and the position of the opening relative to the substrate on the bonding stage is changed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improvement of a bonding apparatus for bonding an electronic component to a substrate in an inert gas atmosphere, and has been developed mainly for a bonding apparatus for bonding an electronic component to a large substrate such as a collective substrate multiple times. It is a thing.

  Conventionally, when a small semiconductor chip such as a light emitter is bonded to a substrate, the diffusibility between the substrate and the semiconductor chip is degraded unless a high-temperature process is performed in a low oxygen concentration atmosphere, and an appropriate bonding strength is obtained. Therefore, there has been known a method of bonding by reducing the oxygen concentration in an inert gas atmosphere such as nitrogen gas.

  As shown in Patent Document 1, the method for reducing the oxygen concentration is provided with coating means (referred to as a reduction box in Patent Document 1) for covering the substrate around the bonding stage, and inactive inside the covering means. Gas (reducing gas in Patent Document 1) was supplied. In order to bond an electronic component to the substrate on the inner side covered with the covering means, an opening through which the tip of the bonding head can be inserted is opened above the covering means.

  Conventionally, since the size of the substrate was small and there was only one bonding location, the opening into which the bonding head is inserted can be made as small as possible. The tip of the bonding head and the opening into which it is inserted The oxygen sneak in between was an acceptable limit. However, recent boards have become collective boards and have become larger in size in consideration of productivity. In such a large aggregate substrate, since there are several bonding positions, the opening into which the tip of the bonding head is inserted cannot be made small, and oxygen wraparound between the opening and the bonding head tip can be prevented. I can't.

Japanese Patent Laid-Open No. 11-74314

  The present invention makes it possible to change the position of the bonding head tip insertion opening provided at the upper part of the covering means, and even if the opening into which the tip of the bonding head is inserted is made as small as possible, it is not as large as a collective substrate. It is an object of the present invention to provide a bonding apparatus capable of bonding an electronic component to a substrate having a number of bonding positions in an inert gas atmosphere.

The first invention employs the following means in the bonding apparatus in order to solve the above problems.
First, a bonding head for holding an electronic component, a bonding stage for supporting a substrate on which the electronic component is mounted, and an opening for covering the periphery and top of the substrate on the bonding stage and inserting the tip of the bonding head at the top. And a bonding apparatus for bonding an electronic component a plurality of times at different bonding positions on a single substrate in an inert gas atmosphere, comprising a covering means having a gas supply means for supplying an inert gas to the inside covered with the covering means. To do.

  Second, the covering means includes an outer peripheral member that surrounds the periphery of the substrate, an upper member that covers the upper portion of the substrate and has an opening for inserting the tip of the bonding head, and a coupling means that closely contacts the outer peripheral member and the upper member. With.

  Third, the close state between the outer peripheral member and the upper member is released, and the upper member is moved relative to the outer peripheral member, so that the position of the opening of the upper member relative to the substrate on the bonding stage can be changed.

  The second invention is the bonding according to the first invention, further comprising a moving means for moving the upper member relative to the outer peripheral member in accordance with the relative movement of the bonding head with respect to the bonding stage in accordance with the change of the bonding position on the substrate. Device.

  In the present invention, since the position of the insertion opening at the tip of the bonding head provided on the upper part of the covering means can be changed, the position of the opening can be moved to the target bonding position. Therefore, the opening into which the tip of the bonding head is inserted can be made as small as possible when bonding at one bonding position. For this reason, it has become a bonding apparatus that can easily bond electronic components in an inert gas atmosphere even to a large substrate such as a collective substrate having a large number of bonding positions.

  Since bonding is performed in an inert gas atmosphere, the use of flux is unnecessary, the cleaning process can be omitted, and the production cost can be reduced. In particular, in the case of a thin film electrode such as a light emitter, it was difficult to remove the flux even after cleaning. However, since the flux was unnecessary, not only the production cost was reduced but also the performance of the electronic product after bonding. Even high quality can be obtained.

Hereinafter, embodiments of the present invention will be described together with examples according to the drawings.
An outline of the flip chip bonder used in the present invention will be described. The flip chip bonder in the embodiment is an apparatus for bonding a semiconductor chip 1 as an electronic component to a collective substrate 2 having several bonding positions by a plurality of bonding operations. As the collective substrate 2 in the embodiment, a substrate in which the semiconductor chip 1 is bonded to four different locations is used.

  As shown in FIG. 1, the flip chip bonder includes a bonding head 3 having a bonding tool 4 that holds the semiconductor chip 1 by suction, a chip supply unit 5 that supplies the semiconductor chip 1 to the bonding tool 4, and a collective substrate 2. A substrate stage 6 as a bonding stage that is placed and bonded, a head Y-axis moving mechanism 7 that moves the bonding head 3 between a chip supply position of the chip supply unit 5 and a bonding position on the substrate stage 6; A nitrogen purge block 8, a nitrogen purge hood 9 and a hood Y-axis moving mechanism 10 serving as coating means in the present invention, and a nitrogen gas supply mechanism serving as gas supply means for supplying an inert gas in the present invention are provided.

  The bonding head 3 is provided on a moving plate 11 of a head Y-axis moving mechanism 7 for moving in the Y-axis direction (left-right direction in FIG. 1), a bonding tool 4 that holds the semiconductor chip 1 by suction, A bonding head body 13 mounted on the plate 11 via a head Z-axis moving mechanism 12 so as to be movable up and down, and disposed in the bonding head body 13 to move the bonding tool 4 in the θ-axis direction (rotation direction). A θ-axis moving mechanism and a pulse heater device for heating the semiconductor chip 1 held by the bonding tool 4 are provided. As a result, the bonding head 3 has a mechanism for moving along the Y axis, Z axis, and θ axis and heating the semiconductor chip.

  The bonding head 3 sucks and holds the semiconductor chip 1 on the bonding tool 4 at the supply position of the chip supply unit 5, moves and descends, mounts the semiconductor chip 1 on one bonding position of the collective substrate 2, and heats it. Join, cool and fix and complete the first bond. After that, it rises again and returns to the chip supply position, the next semiconductor chip 1 is sucked and held, and the operation of moving and bonding the next semiconductor chip 1 to a different bonding position on the collective substrate 2 is repeated. The bonding head 3 includes a top camera 14 that can move in the Y-axis direction and the Z-axis direction together with the bonding head 3.

  The substrate stage 6 is provided with a heating cartridge heater 15, a nitrogen gas supply path 16, a vacuum suction path for substrate adsorption (not shown), and a substrate vacuum hole 24 for substrate adsorption. The substrate stage 6 includes a stage X-axis moving mechanism 18 in the X-axis direction (a direction perpendicular to the Y-axis in the front-rear direction). A bottom camera 19 is provided between the chip supply unit 5 and the substrate stage 6 below the movement path of the bonding tool 4.

  On the substrate stage 6, a nitrogen purge block 8 constituting a part of the coating means in the present invention is provided. The nitrogen purge block 8 is formed on the substrate stage 6 as an outer peripheral member having a size that surrounds the periphery of the collective substrate 2, with an empty portion 20 having a size that allows the collective substrate 2 to be disposed at the center. In the nitrogen purge block 8, a vacuum groove 17 is formed for adhering the nitrogen gas jet 25 to the inner wall surface of the empty portion 20 and the nitrogen purge hood 9 on the upper surface. The vacuum groove 17 is connected to a vacuum suction source (not shown) by a suction passage 21, and the nitrogen gas outlet 25 is connected to a gas supply means such as a cylinder (not shown) to constitute a gas supply mechanism. The stage 6, the nitrogen purge block 8, and the nitrogen gas supply path 16 formed in the nitrogen gas ejection part 23 are connected.

  The nitrogen purge hood 9 is a plate-like body with a head insertion opening 22 into which the bonding tool 4 at the tip of the bonding head 3 is inserted at the center. The head insertion opening 22 is formed as small as possible to the extent that the bonding tool 4 of the bonding head 3 can be inserted. The nitrogen purge hood 9 can be tightly coupled to the upper surface of the nitrogen purge block 8 by the suction force of the vacuum groove 17, and further, the upper surface of the nitrogen purge block 8 is removed by the hood Y-axis moving mechanism 10 by releasing the adhesion. It can be moved in the Y-axis direction. A second-layer nitrogen gas ejection portion 23 is provided around the head insertion opening 22 of the nitrogen purge hood 9.

The operation of the flip chip bonder of the embodiment will be described below.
First, the semiconductor chip 1 is supplied by a wafer or a chip tray and is sucked and held by the bonding tool 4 of the bonding head 3. The semiconductor chip 1 sucked and held by the bonding tool 4 is subjected to image processing by the bottom camera 19 and the sucked state is recognized. On the other hand, in the collective substrate 2, the nitrogen purge hood 9 is retracted by the hood Y-axis moving mechanism 10 in a state where the suction force of the vacuum groove 17 is released, and the empty portion of the nitrogen purge block 8 installed on the substrate stage 6 is removed. The upper part of the substrate 20 is opened, and is carried into the empty portion 20 and fixed on the substrate stage 6 by the suction force of the substrate vacuum hole 24.

  The substrate stage 6 is moved by the stage X-axis moving mechanism 18, the nitrogen purge hood 9 is moved by the hood Y-axis moving mechanism 10, and the head insertion opening 22 is arranged at a predetermined bonding position on the collective substrate 2. Thereafter, the top camera 14 performs image processing on the collective substrate. It is image processing for bonding position alignment.

  At this time, the purge nitrogen gas is passed through the heated nitrogen gas supply path 16 inside the substrate stage 6 to heat the nitrogen gas. The heated nitrogen gas is jetted from four directions toward the collective substrate 2 from a nitrogen gas jet port 25 provided in the inner peripheral portion of the nitrogen purge block 8. By heating the nitrogen gas in this way, the semiconductor chip 1 and the collective substrate 2 are prevented from being cooled by the injection of the nitrogen gas. The nitrogen gas is heated by disposing a nitrogen gas supply path 16 in the vicinity of the cartridge heater 15 for heating the substrate stage 6 so that no special heating means is required. Thereafter, the bonding head 3 is lowered and the bonding tool 4 is inserted into the empty portion 20 from the head insertion opening 22. At this time, a nitrogen purge hood 9 is provided above the nitrogen purge block 8 and is fixed by the suction force of the vacuum groove 17, so that oxygen can be prevented from being circulated. Thereafter, the oxygen concentration in the empty portion 20 of the nitrogen purge block 8 is measured, and when it reaches an appropriate value, the position is corrected according to the image processing, the bonding tool 4 is further lowered, and the semiconductor chip 1 is assembled to the collective substrate. 2 to be bonded. When correcting the position, the suction force of the vacuum groove 17 is released, and the hood Y-axis moving mechanism 10 is operated in accordance with the movement of the bonding head 3 in the Y-axis direction. The hood 9 is moved. Further, since the second layer nitrogen gas ejection portion 23 is provided around the head insertion opening portion 22 of the nitrogen purge hood 9, nitrogen gas is also ejected from here, and the bonding tool 4 and the head insertion opening portion 22 are in contact with each other. Oxygen wraparound from the gap is more reliably prevented.

  After the first semiconductor chip 1 is bonded at a predetermined position, the bonding head 3 moves up and returns to the chip supply position to hold the next semiconductor chip 1 by suction. At this time, in order to move the head opening 22 to the second bonding position, the nitrogen purge hood 9 is moved in the Y-axis direction by the hood Y-axis moving mechanism 10 or by the stage X-axis moving mechanism 18. The substrate stage 6 is moved in the X-axis direction, or these combined operations are performed.

  In the embodiment, the nitrogen gas is heated and supplied. However, the supply pressure of the nitrogen gas through the nitrogen gas supply path 16 can be switched between high and low. The heated nitrogen gas can be blown from 25 and sprayed at a high pressure after bonding to cool the bonding tool 4, the substrate stage 6, the semiconductor chip 1 and the collective substrate 2.

The perspective explanatory view showing the outline of the flip chip bonder according to the embodiment Explanation front view showing covering means and gas supply mechanism on substrate stage Plane explanatory diagram of the nitrogen purge block Plane explanatory diagram of nitrogen purge hood

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Semiconductor chip 2 ... Collective substrate 3 ... Bonding head 4 ... Bonding tool 5 ... Chip supply part 6 ... Substrate stage 7 Head Y axis moving mechanism 8 Nitrogen purge block 9 Nitrogen purge hood 10 ... Hood Y axis moving mechanism 11 ... Moving plate 12 ... Head Z axis moving mechanism 13 ... Bonding head body 14 ... Top camera 15 ... Cartridge heater 16 ... Nitrogen gas supply path 17 ... Vacuum groove 18 ... Stage X Axis movement mechanism 19 ... Bottom camera 20 ... Empty part 21 ... Suction passage 22 ... Head insertion opening 23 ... Nitrogen gas ejection part 24 ... Substrate vacuum hole 25 ... Hydrogen gas injection port

Claims (2)

A bonding head for holding electronic components;
A bonding stage that supports a substrate on which electronic components are mounted;
Coating means having an opening for covering the periphery and top of the substrate on the bonding stage and inserting the tip of the bonding head at the top;
Gas supply means for supplying an inert gas to the inside covered with the covering means,
A bonding apparatus that bonds electronic components to different positions on a single substrate in an inert gas atmosphere multiple times.
The covering means includes an outer peripheral member that surrounds the periphery of the substrate, an upper member that covers the upper portion of the substrate and has an opening for inserting the tip of the bonding head, and a coupling means that closely contacts the outer peripheral member and the upper member.
A bonding apparatus characterized in that the close state between the outer peripheral member and the upper member is released and the upper member is moved relative to the outer peripheral member to change the position of the opening of the upper member relative to the substrate on the bonding stage.
2. The bonding apparatus according to claim 1, further comprising a moving means for moving the upper member relative to the outer peripheral member in accordance with the relative movement of the bonding head relative to the bonding stage in accordance with the change of the bonding position on the substrate.

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