JP7163047B2 - Mounting apparatus, mounting method, and semiconductor device manufacturing method using the same - Google Patents

Description

The present invention relates to a mounting method and mounting apparatus for mounting an electronic component having bumps on a substrate having electrodes. In particular, the present invention relates to a mounting apparatus and a mounting method for flip-chip mounting a semiconductor chip having bumps on a substrate having electrodes.

2. Description of the Related Art In the development of electronic equipment in recent years, there are various demands for electronic components to be mounted therein, and in order to meet these demands, rapid cycle development is being pursued. As part of this, as a method of mounting electronic components such as semiconductor chips on substrates, flip-chip mounting is becoming popular in order to meet demands for shortening transmission distances and miniaturization. Flip-chip mounting is a method of bonding bumps of an electronic component to electrodes of a substrate, and a method of using solder bumps as the bumps is often adopted (FIG. 12(a)).

Also in flip-chip mounting, bumps are being miniaturized and the pitch between bumps is being narrowed against the background of the demand for higher mounting density. On the other hand, in the method using solder bumps, solder S is used at the tip of the copper pillar (FIG. 12(b)). However, as the diameter of the copper pillar P decreases, the amount of solder S decreases. The proportion increases and adversely affects the reliability of the joint.

For this reason, along with the improvement in mounting density, there is a demand for a construction method that does not use solder. The method using a metal particle paste uses a metal particle paste in which metal nanoparticles such as silver nanoparticles with a particle size smaller than 1 μm are dispersed in a resin, and the metal nanoparticles are sintered at a temperature lower than the melting point. It is used to form a metallic bond.

In particular, if a copper nanoparticle paste in which copper nanoparticles are dispersed as described in Non-Patent Document 1 is used, copper is usually used as the material for the pillar P and the electrode E, so copper and copper The sintered copper will join, and the problem of intermetallic compound IMC can be solved.

A mounting process using metal particle paste is shown in FIGS. FIG. 13(a) shows a state in which a semiconductor chip C having pillar bumps PB is placed on a flat plate T coated with a metal particle paste NP having a predetermined thickness. In b) the underside of the pillar bumps PB is dipped into the metal particle paste NP. After that, when the semiconductor chip C is lifted, a state is obtained in which a predetermined amount of the metal particle paste NP is transferred to the tip side (lower side) of the pillar bump PB.

FIG. 14A shows a state in which a semiconductor chip C having a predetermined amount of metal particle paste NP transferred to the tip side of the pillar bumps PB is placed on the substrate W with the pillar bumps PB and the electrodes E of the substrate W aligned. is. The semiconductor chip C is gradually lowered from this state, and the state where the metal particle paste NP on the tip side of the pillar bump PB is in contact with the electrode E is shown in FIG. 14(b).

After that, it is necessary to heat and sinter the metal particle paste NP. As a method of heating the metal particle paste NP, in the state shown in FIG. and a method (so-called reflow) in which the substrate W on which the semiconductor chip C is temporarily fixed via the metal particle paste NP as shown in FIG. 14C is moved into the heating furnace 200 and heated.

JP 2007-208082 A

J Zurcher et al. , "Nanoparticle Assembly and Sintering Towards All-Copper Flip Chip Interconnects," in Proc. 65th IEEE Electronic Components and Technology Conf. (ECTC), San Diego, CA, May 26-29, 2015, pp, 1115-1121.

Since the metal nanoparticles in the metal particle paste NP are coated with a resin, their surfaces are difficult to oxidize. However, in the vicinity of the surface layer of the metal particle paste NP, the surfaces of the metal nanoparticles in contact with the atmosphere are in a state of being easily oxidized.

For this reason, in the process from FIG. 13(b) to FIG. 14(b), if the surface of the metal particle paste NP is exposed to the atmosphere for a long time, the metal particle paste contacting the electrode E in the state of FIG. 14(b) The metal nanoparticles on the NP surface are oxidized, leaving a metal oxide layer (which is an insulator) at the interface with the electrode E after sintering, which may adversely affect conductivity. In particular, since copper nanoparticles are easily oxidized, countermeasures against surface oxidation are essential.

Therefore, as shown in FIG. 14(c), when sintering is performed in the heating furnace 200, the oxygen concentration in the heating furnace 200 is lowered, or the heating is performed while the heating furnace 200 is made to contain a reducing gas. It is also possible to restore conductivity by reducing the oxidized moieties.

However, when performing sintering in the heating furnace 200, it is necessary to move the substrate W on which the semiconductor chip C is temporarily fixed via the metal particle paste NP into the heating furnace 200. Since the semiconductor chip C may be displaced with respect to the substrate W, it is not preferable. In particular, when mounting a semiconductor chip C having small-diameter pillar bumps PB, even a slight misalignment adversely affects the performance of the semiconductor device after mounting.

The present invention has been made in view of the above problems. A mounting apparatus, a mounting method, and a method of manufacturing a semiconductor device using the same are provided, which are capable of performing reliable mounting under low pressure.

In order to solve the above problems, the invention according to claim 1 sinters the metal particle paste interposed between the bumps of the electronic component and the electrodes of the substrate to mount the electronic component on the substrate. A mounting device,
a stage capable of holding the substrate from the surface opposite to the surface on which the electrodes exist and moving the substrate in a surface direction; and a bonding head with a built-in heater, and a shape covering the stage, and an opening through which the bonding head can pass at a position facing the bonding head, with respect to the stage a stage cover that can move up and down by means of a nozzle; a nozzle that discharges gas into the stage cover; and a controller for controlling operations of the stage, the bonding head, and the nozzle.

The invention according to claim 2 is the mounting apparatus according to claim 1,
In the mounting apparatus, the paste transfer section is provided so as to move together with the stage.

The invention according to claim 3 is the mounting apparatus according to claim 1,
further comprising transport means for transporting the semiconductor chip to the bonding head;
It is a mounting apparatus in which the paste transfer section is provided in the conveying means.

The invention according to claim 4 is the mounting apparatus according to any one of claims 1 to 3,
The mounting apparatus further includes recognition means for acquiring positional information of the electronic component and the board .

The invention according to claim 5 is a mounting method for mounting an electronic component on a substrate using the mounting apparatus according to any one of claims 1 to 4,
a transfer step of transferring the metal particle paste to the bumps; an alignment step of aligning the electronic component and the substrate so that the bumps are arranged opposite to the electrodes; and a metal particle transferred to the bumps. Mounting comprising: an approaching step of bringing the electronic component closer to the substrate until the paste contacts the electrode and the distance between the bump and the electrode falls within a predetermined range; and a sintering step of heating the metal particle paste. The method.

The invention according to claim 6 is a mounting method for mounting an electronic component on a substrate using the mounting apparatus according to any one of claims 1 to 4,
a transfer step of transferring the metal particle paste to the bumps; an alignment step of aligning the electronic component and the substrate so that the bumps are arranged opposite to the electrodes; and a metal particle transferred to the bumps. an approaching step of bringing the electronic component closer to the substrate until the paste contacts the electrode and the distance between the bump and the electrode falls within a predetermined range; and a sintering step of heating the metal particle paste,
In the mounting method, at least in the sintering process, the nozzle emits an inert gas to reduce the oxygen concentration in the stage cover.

The invention according to claim 7 is a mounting method for mounting an electronic component on a substrate using the mounting apparatus according to any one of claims 1 to 4,
a transfer step of transferring the metal particle paste to the bumps; an alignment step of aligning the electronic component and the substrate so that the bumps are arranged opposite to the electrodes; and a metal particle transferred to the bumps. an approaching step of approaching the electronic component to the substrate until the paste contacts the electrode and the distance between the bump and the electrode falls within a predetermined range; and a sintering step of heating the metal particle paste. In the mounting method, in the sintering process, the nozzle emits a gas containing a reducing element to create a reducing atmosphere inside the stage cover.

The invention according to claim 8 is the mounting method according to any one of claims 5 to 7,
In the mounting method, the electronic component is pressed against the substrate in the sintering step.

According to a ninth aspect of the present invention, there is provided a method of manufacturing a semiconductor device, wherein a semiconductor chip is used as the electronic component, and the semiconductor chip is mounted on a substrate by the mounting method according to any one of the fifth to eighth aspects.

According to the present invention, when bonding the bumps of the semiconductor chip and the electrodes of the substrate using the metal particle paste, reliable mounting with excellent mounting position accuracy and conductivity of the joints can be realized.

It is a figure which shows the mounting apparatus which concerns on embodiment of this invention. It is a figure explaining the stage and bonding head of the mounting apparatus which concern on embodiment of this invention. It is a block diagram showing the control configuration of the mounting apparatus according to the embodiment of the present invention. (a) is a diagram showing a state in which a paste transfer portion is arranged directly below the semiconductor chip in the transfer step according to the embodiment of the present invention; (c) is a diagram showing a state after the metal particle paste is transferred to the pillar bumps of the semiconductor chip in the transfer step. (a) is a view showing a state before alignment in the alignment process according to the embodiment of the present invention; (b) is a view showing a state after alignment in the same alignment process; (a) is a diagram for explaining the process of approaching the semiconductor chip to the substrate in the approaching step according to the embodiment of the present invention; (c) is a diagram showing a state after the sintering process according to the embodiment of the present invention is completed. It is a figure explaining the state at the time of the mounting apparatus which concerns on embodiment of this invention performing a transfer process. (a) It is a figure which shows the external appearance of the mounting apparatus based on the modification of embodiment of this invention, (b) It is a figure which shows the structure of the mounting apparatus which concerns on the modification of embodiment of this invention. (a) It is a figure explaining the conveying means which conveys a semiconductor chip directly under a bonding head, (b) It is a figure which shows the structural example of the said conveying means. (a) A mounting apparatus according to another embodiment of the present invention, showing a state before the bonding head holds the semiconductor chip. (b) The same mounting apparatus, after the bonding head holds the semiconductor chip. It is a figure which shows a state (c) It is a figure explaining the transfer process using the paste transfer part provided in the conveyance means in the same mounting apparatus. It is a figure which shows an example of the paste transfer part provided in the conveyance means. (a) is a diagram illustrating bonding in flip chip mounting, and is a cross-sectional view of a bonding portion using a solder bump; (b) is a diagram illustrating the bonding, using a pillar bump having solder at the tip; 1 is a cross-sectional view of a welded joint; FIG. (a) A diagram for explaining the process of transferring the metal particle paste to the pillar bumps of the semiconductor chip, showing a state in which the semiconductor chip is placed on top of the metal particle paste. FIG. 13C is a diagram showing a state in which the semiconductor chip is immersed in the particle paste; (a) A diagram showing a state in which the semiconductor chip is placed on the substrate in the step of mounting the semiconductor chip having the metal particle paste transferred to the pillar bumps on the substrate. FIG. 4C is a diagram showing a state in which pillar bumps are connected to electrodes;

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a mounting apparatus 1 according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of main parts of the mounting apparatus 1, and FIG. A mounting apparatus 1 mounts a semiconductor chip C, which is an electronic component, on a substrate W. , a paste transfer unit 9 and a control unit 10 . The semiconductor chip C has pillar bumps PB as shown in FIG. 13(a), and the substrate W has electrodes E as shown in FIG. 14(a). When mounting the semiconductor chip C on the substrate W, the semiconductor chip C is mechanically fixed on the substrate W while the pillar bumps PB and the electrodes E are electrically connected.

In this embodiment, copper is assumed as the material of the pillar bumps PB and the electrodes E, but the material is not limited to this. Any other metal material may be used as long as the conductivity and mechanical properties are suitable for the application, and the pillar bumps PB and the electrodes E may be made of different materials. Furthermore, a nickel or gold thin film may be formed on the surfaces of the pillar bumps PB and/or the electrodes E by plating or the like.

The base 2 is a main structure that constitutes the mounting apparatus 1 . The base 2 is configured to have sufficient rigidity. A base 2 supports a support frame 3 and a stage 4 .

The support frame 3 supports the pressing unit 5 . The support frame 3 is configured to extend from the vicinity of the stage 4 of the base 2 in the Z direction.

The stage 4 moves the substrate W while holding it from the side opposite to the side where the electrodes E are present. The stage 4 is composed of a Y-direction driving unit 4a, an X-direction driving unit 4b, and a suction table 4c. The stage 4 is mounted on the base 2, and configured so that the X-direction drive unit 4b can move the suction table 4c in the X direction, and the Y-direction drive unit 4a can move (the X-direction drive unit 4b and) the suction table 4c in the Y direction. It is Further, as shown in FIG. 2, the suction table 4c has a substrate suction hole 4H for sucking the substrate W. there is By operating the vacuum pump 8 and the valve 4V provided in the flow path leading to the vacuum pump 8, the inside of the substrate suction hole 4H can be depressurized, and the substrate W can be held by suction on the suction table 4c.

With the above configuration, the stage 4 can move the substrate W sucked by the suction table 4c on the base 2 in the in-plane directions of the substrate W, ie, the X direction and the Y direction.

The pressure unit 5 is for moving the bonding head 6 . The pressurizing unit 5 is configured to generate a driving force in the axial direction of the ball screw by rotating the ball screw with a servomotor (not shown). The pressurizing unit 5 is configured to generate a driving force (pressurizing force) in the Z direction in which the axial direction of the ball screw is perpendicular to the substrate W. As shown in FIG. The pressurizing unit 5 is configured to arbitrarily set the load Pz in the Z direction by controlling the output of the servomotor. From the viewpoint of positional deviation during bonding, it is desirable that the bonding head 6 be configured to be movable only in the Z direction.

In this embodiment, the pressurizing unit 5 is composed of a servomotor and a ball screw, but is not limited to this, and may be composed of a pneumatic actuator, a hydraulic actuator, or a voice coil motor. Moreover, the pressure unit 5 may have a function of rotating the bonding head 6 in the θ direction.

The bonding head 6 transmits the driving force of the pressure unit 5 to the semiconductor chip C and heats the semiconductor chip. The bonding head 6 comprises an attachment tool 61, a heater 62, a heat insulation block 63, and a head body 64, as shown in FIG.

An electronic component suction hole 6</b>H is provided in the attachment tool 61 , and the electronic component suction hole 6</b>H communicates with the vacuum pump 8 via an in-head channel 6</b>E formed in the bonding head 6 . Here, the vacuum pump 8 and the valve 6V provided in the flow path leading to the vacuum pump 8 are operated to depressurize the inside of the electronic component suction hole 6H, and the semiconductor chip C is moved from the side opposite to the side where the bumps are present to the attachment tool 61. can be adsorbed and held. Further, the heater 62 incorporates an electric heating member such as a ceramic heater, and may incorporate a temperature sensor for heater temperature control.

The bonding head 6 is attached to a ball screw and nut (not shown) that constitute the pressure unit 5 . That is, the bonding head 6 (the attachment tool 61 thereof) is arranged so as to face the stage 4 (the suction table 4c thereof) in parallel. That is, the semiconductor chip C can be brought closer to the substrate W by moving the bonding head 6 in the Z direction by the pressure unit 5 .

The image recognition means 7 acquires the positional information of the semiconductor chip C and the substrate W from images. The image recognition means 7 image-recognizes the alignment marks on the upper surface of the substrate W held by the stage 4 and the alignment marks of the semiconductor chip C held by the bonding head 6 to identify the substrate W and the semiconductor chip C. It is configured to acquire position information (in the XY plane).

The paste transfer portion 9 stores metal particle paste NP having a predetermined thickness, and has a saucer shape in which at least all the pillar bumps PB of the semiconductor chip C are immersed to the same depth. A predetermined amount of the metal particle paste NP having a predetermined thickness is supplied by a paste supply means (not shown). As a specific paste supply means, a stencil printing mechanism, a dispenser, or the like is used.

In the mounting apparatus 1 shown in FIG. 1, the paste transfer unit 9 is arranged to be connected to the suction table 4c. It is configured to be movable in the X direction by the unit 4b.

The controller 10 is connected to the stage 4, the nozzle 41, the pressure unit 5, the bonding head 6, and the image recognition means 7, as shown in FIG. Also, the vacuum pump 8 may be independent from the control section 10 or may be connected to the control section 10 . The control unit 10 may have a configuration in which a CPU, a ROM, an HDD, etc. are connected via a bus, or may be configured from a one-chip LSI. The control unit 10 stores various programs and data for acquiring and controlling signals from the connection destination.

The control section 10 is connected to the stage 4 and individually controls the Y-direction driving unit 4a and the X-direction driving unit 4b. Further, the control unit 10 controls whether or not the substrate W is adsorbed by the adsorption table 4c by controlling the valve 4V. Therefore, the controller 10 can arbitrarily change the position of the substrate W in the XY plane by controlling the Y-direction suction unit 4a, the Y-direction suction unit 4b, and the valve 4V.

The controller 10 is connected to the pressure unit 5 and can control the height of the pressure unit 5 in the Z direction and the load Pz. If the pressure unit 5 has a function of rotating the bonding head 6 in the .theta. direction, the controller 5 may control the rotation angle of the bonding head in the .theta. direction.

The controller 10 is connected to the bonding head 6 and can control the heater 62 to a predetermined temperature. Further, the control unit 10 controls whether or not the semiconductor chip C is sucked by the attachment tool 61 by controlling the valve 6V.

The control unit 10 is connected to the image recognition means 7, controls the position of the image recognition means 7, and can acquire the position information of the substrate W and the semiconductor chip C from the image information.

When the control unit 10 is connected to the vacuum pump 8, it controls the vacuum pump 8 to operate before starting the mounting operation. Therefore, whether or not the substrate W and the semiconductor chip C are attracted is controlled by opening and closing the valves 4V and 6V.

The process of mounting the semiconductor chip C on the substrate W using the mounting apparatus 1 described with reference to FIGS. 1 to 3 will be described below with reference to FIGS. 4 to 6. FIG.

First, FIG. 4 is a diagram for explaining the transfer process. 4A shows a state in which the attachment tool 61 of the bonding head 6 sucks and holds the semiconductor chip C transported by transport means (not shown), and the paste transfer section 9 is arranged directly below the semiconductor chip C. FIG. there is Here, the paste transfer section 9 is arranged directly below the semiconductor chip C as shown in FIG. . Incidentally, when adjusting the position of the paste transfer portion 9 directly below the semiconductor chip C, the image recognition means 7 may be used.

After arranging the paste transfer section 9 directly below the semiconductor chip C as shown in FIG. 4A, the control section 10 controls the pressure unit 5 to lower the bonding head 6 by a predetermined length. By this operation, the pillar bumps PB of the semiconductor chip C are immersed in the metal particle paste NP stored in the paste transfer section 9 .

Here, the metal particle paste NP targeted by the present invention is obtained by dispersing metal particles containing metal nanoparticles having a particle size of less than 1 μm in a resin binder. In this embodiment, it is assumed that the pillar bumps PB of the semiconductor chip C and the electrodes E of the substrate W are made of copper. Other metal nanoparticles such as silver nanoparticles, tin nanoparticles, and indium nanoparticles may be used depending on the application as a semiconductor element after mounting and the conditions such as the heating temperature during sintering. As the binder resin, epoxy resin is generally used, but polyimide resin, acrylic resin, etc. may also be used. may

After the immersion, when the control unit 10 controls the pressure unit 5 to raise the bonding head 6, the metal particle paste NP is transferred to the individual pillar bumps PB of the semiconductor chip C as shown in FIG. 4(c). state.

FIG. 5 is a diagram for explaining the alignment process. In the alignment process, first, the control unit 10 controls the Y-direction driving unit 4a and the X-direction driving unit 4b of the stage 4 to move the substrate W in the horizontal direction, and the mounted portion of the substrate W is aligned with the semiconductor chip C. After arranging in the vicinity directly under the pillar bump PB, alignment is performed so that the electrode E is arranged directly under the pillar bump PB. When performing alignment using the image recognition means 7, image recognition may be performed between FIGS. 5(a) and 5(b). is not preferred. Therefore, before the transfer process, position confirmation is performed using the image recognition means 7 so that the electrode E is arranged directly below the pillar bump PB, and alignment based on the position information stored at that time is performed after the transfer process. may

5(b), the controller 10 controls the pressure unit 5 to lower the bonding head 6 (FIG. 6(a)), and the metal particle paste NP transferred to the pillar bumps PB. is brought into contact with the electrode E (FIG. 6(b)), and when the distance between the pillar bump PB and the electrode E is within a predetermined range, the lowering of the bonding head 6 is stopped. The process until the bonding head 6 is lowered and stopped is the approaching process. When measuring the distance between the pillar bump PB and the electrode E, the distance may be measured using optical means. A method of estimating the distance from the repulsive force may also be used.

After that, from the state of FIG. 6B, the heater 62 of the bonding head 6 is heated to heat and sinter the metal particle paste NP, which is the sintering step. At this time, the sintering temperature varies depending on the characteristics of the metal particle paste NP. The temperature of heater 62 is controlled.

Even if sintering is performed by heating the heater 62 while maintaining the position at which the bonding head 6 stopped descending in the approaching step, the sintered metal particle paste NP ensures electrical connection between the pillar bumps PB and the electrodes E. can. However, during the sintering process, the binder resin of the metal particle paste NP shrinks and degasses. A sintered body may be formed in a large amount, and sufficient electrical conductivity and mechanical strength may not be obtained. Therefore, in the sintering process, pressure may be applied to the bonding head 6 by the pressurizing unit 5 so that the metal particle paste NP is sintered while the pillar bumps PB and the electrodes E gradually approach each other. By applying an appropriate pressure to the bonding head 6 during sintering, the contact area between the metal particles after sintering increases and the spatial density increases, so that electrical conductivity and mechanical strength can be improved.

After the metal particle paste NP is sintered, the semiconductor chip C is released from the attachment tool 61, and then the control unit 10 controls the pressure unit 5 to raise the bonding head 6 (FIG. 6(c)). ). The semiconductor chip C is then mounted on the substrate W, and a semiconductor device is manufactured through processes such as separation of the substrate W as necessary.

In the mounting method of the present embodiment using the mounting apparatus 1 as described above, in a state in which the semiconductor chip C is adsorbed to the attachment tool 61 of the bonding head 6, the metal particle paste NP is transferred to the pillar bumps PB, and then transferred to the pillar bumps PB. The process up to contact between the transferred metal particle paste NP and the electrode E of the substrate W can be performed in a short time. Therefore, oxidation of (the metal particles of) the metal particle paste NP in contact with the electrodes E can be suppressed, and the pillar bumps PB and the electrodes E can be joined with good conductivity.

Moreover, by sintering the metal particle paste NP in a state in which the semiconductor chip C and the substrate W are aligned, mounting with excellent positional accuracy can be performed.

As described above, by using the mounting apparatus 1 shown in FIG. 1, the oxidation of (the metal particles of) the metal particle paste NP in contact with the electrode E can be suppressed. FIG. 8 shows a mounting device 101 as a modified example. FIG. 8(a) shows the appearance of the mounting apparatus 101, and FIG. 8(b) shows the internal configuration hidden in the appearance of FIG. 8(a).

As can be seen from FIG. 8B, the basic configuration of the mounting apparatus 101 is the same as that of the mounting apparatus 1 shown in FIG.

The stage cover 40 is a cover that covers the stage 4 and has an opening 40H on the upper surface facing the bonding head 6 . Here, it is desirable that the gap between the bonding head 6 and the opening 40H (the edge thereof) is 5 mm or less, while the opening 40H has a shape that allows the bonding head 6 to pass therethrough without hindrance when it moves up and down. The substrate W can be moved in and out of the stage cover 40 by providing an opening/closing portion on the side surface of the stage cover 40, or by raising the entire stage cover 40 to move the substrate W in and out. .

The nozzle 41 discharges gas into the interior covered with the stage cover 40, and the controller 10 controls opening/closing of a valve (not shown) to determine whether or not the gas is discharged. Also, a valve capable of controlling the flow rate or pressure may be used.
The mounting method using this mounting apparatus 101 includes a transfer process, an alignment process, an approaching process, and a sintering process, as in the case of using the mounting apparatus 1. At least in the sintering process, the nozzle 41 is filled with an inert gas. By releasing the oxygen concentration in the stage cover 40, the oxygen concentration in the stage cover 40 is reduced, the oxidation of (the metal particles of) the metal particle paste NP can be further suppressed, and the bonding reliability is improved by improving the conductivity and mechanical strength. can be increased. A rare gas such as argon or xenon is also effective as the inert gas, but it is preferable to use relatively inexpensive nitrogen gas. The discharge of the inert gas by the nozzle 41 is not limited to the sintering process, and may be performed in each process of the transfer process, the alignment process, and the approaching process.

Alternatively, a reducing gas may be used as the gas discharged from the nozzle 41 . The reducing gas is preferably an inert gas containing a small amount of reducing gas such as chlorine or fluorine. At least in the sintering process, the nozzle 41 emits reducing gas, so that the inside of the stage cover 40 becomes a reducing atmosphere, and an effect of reducing the oxide film of (the metal particles of) the metal particle paste NP can also be expected. Furthermore, if the reducing gas is released into the stage cover 40, it is possible to use oxide nanoparticles (for example, copper oxide nanoparticles) instead of metal nanoparticles as the metal particle paste NP. . However, since the reducing gas may adversely affect the structural materials used in the mounting device 101 and the human body, it should be handled with care.

By the way, when supplying the semiconductor chip C to the attachment tool 61 of the bonding head 6, a chip slider 17 as shown in FIG. 9(a) is generally used. The chip slider 17 slides along the transport rail while holding the semiconductor chip C in the transport means 11 shown in FIG. 9(b). If the semiconductor chip is placed directly under the tool 61, then the bonding head 6 descends and the attachment tool 61 holds the semiconductor chip C by suction.

Therefore, as another embodiment of the present invention using this mechanism, a paste transfer section 19 (having the same form as the paste transfer section 9 of the mounting apparatus 1) is attached to the transfer section slider 18 that performs the same operation as the chip slider 17. An example of mounting is shown in FIG.

10(a) shows a state in which the chip slider 17 holding the semiconductor chip C moves along the transport rail 16 and arranges the semiconductor chip C directly below the attachment tool 61, and FIG. 10(b) shows the state in which the attachment tool 61 shows the state after the semiconductor chip C is sucked and held and lifted. After the state shown in FIG. 10B, the transfer section slider 18 moves along the transport rail 16, and the paste transfer section 19 is arranged directly below the attachment tool 61 (the semiconductor chip C held by it). is shown in FIG. 10(c). Thereafter, the metal particle paste NP is transferred to the pillar bumps PB of the semiconductor chip C by lowering and raising the bonding head 6 as shown in FIGS. 4(a) to 4(c). Thereafter, mounting is completed by performing the positioning process, the approaching process, and the sintering process in the same manner as described with reference to FIGS.

It is also possible to enlarge the chip slider 17 and mount the paste transfer portion 19 together with the semiconductor chip C. It is not preferable from the viewpoint of the process to be mounted on the For this reason, it is preferable to use a conveying means 12 capable of independently moving the chip slider 17 and the paste transfer section 18 as shown in FIG.

By the way, it is necessary to avoid the metal particle paste NP from adhering to the semiconductor chip C itself in the transfer process. The present invention is not limited to the pillar bumps PB as long as it is possible to transfer the .

REFERENCE SIGNS LIST 1 mounting device 2 base 3 frame 4 stage 4a Y-direction drive unit 4b X-direction drive unit 4c suction table 4E exhaust channel 4H substrate suction hole 5 pressure unit 6 bonding head 6H electronic component suction hole 7 image recognition means 8 vacuum pump 9, 19 paste transfer unit 10 control unit 11, 12 transport means 16 transport rail 17 chip slider 18 supply unit slider 40 stage cover 40H opening 41 nozzle 61 attachment tool 62 heater 200 heating furnace C semiconductor chip (electronic component)
E Electrode NP Metal particle paste PB Pillar bump W Substrate

Claims (9)

A mounting device for mounting an electronic component on a substrate by sintering a metal particle paste interposed between a bump of the electronic component and an electrode of the substrate,
a stage capable of holding the substrate from a surface opposite to the surface on which the electrodes are present and moving the substrate in a planar direction;
a bonding head having a function of holding the electronic component from the surface opposite to the surface on which the bumps are present and driving the electronic component toward the substrate, and having a built-in heater;
a stage cover that has a shape that covers the stage, has an opening through which the bonding head can pass at a position facing the bonding head, and is vertically movable with respect to the stage;
a nozzle for discharging gas into the stage cover;
a paste transfer unit accommodated in the stage cover for transferring the metal particle paste to the bumps of the electronic component held by the bonding head;
A mounting apparatus comprising a controller for controlling operations of the stage, the bonding head, and the nozzle. The mounting apparatus according to claim 1,
A mounting apparatus provided so as to move the paste transfer section together with the stage. The mounting apparatus according to claim 1,
further comprising transport means for transporting the semiconductor chip to the bonding head;
A mounting apparatus in which the paste transfer section is provided in the conveying means. The mounting apparatus according to any one of claims 1 to 3,
A mounting apparatus further comprising recognition means for acquiring positional information of the electronic component and the board. A mounting method for mounting an electronic component on a substrate using the mounting apparatus according to any one of claims 1 to 4,
a transfer step of transferring the metal particle paste to the bump;
an alignment step of aligning the electronic component and the substrate so that the bumps are arranged to face the electrodes;
an approaching step of bringing the electronic component closer to the substrate until the metal particle paste transferred to the bump contacts the electrode and the distance between the bump and the electrode falls within a predetermined range;
and a sintering step of heating the metal particle paste. A mounting method for mounting an electronic component on a substrate using the mounting apparatus according to any one of claims 1 to 4,
a transfer step of transferring the metal particle paste to the bump;
an alignment step of aligning the electronic component and the substrate so that the bumps are arranged to face the electrodes;
an approaching step of bringing the electronic component closer to the substrate until the metal particle paste transferred to the bump contacts the electrode and the distance between the bump and the electrode falls within a predetermined range;
A sintering step of heating the metal particle paste,
The mounting method, wherein at least in the sintering process, the nozzle emits an inert gas to reduce the oxygen concentration in the stage cover. A mounting method for mounting an electronic component on a substrate using the mounting apparatus according to any one of claims 1 to 4,
a transfer step of transferring the metal particle paste to the bump;
an alignment step of aligning the electronic component and the substrate so that the bumps are arranged to face the electrodes;
an approaching step of bringing the electronic component closer to the substrate until the metal particle paste transferred to the bump contacts the electrode and the distance between the bump and the electrode falls within a predetermined range;
a sintering step of heating the metal particle paste, and at least in the sintering step, the nozzle emits a gas containing a reducing element to create a reducing atmosphere inside the stage cover. The mounting method according to any one of claims 5 to 7,
A mounting method in which the electronic component is pressed against the substrate in the sintering step. A method of manufacturing a semiconductor device, wherein a semiconductor chip is used as the electronic component, and the semiconductor chip is mounted on a substrate by the mounting method according to any one of claims 5 to 8.

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