JP3850351B2 - Electronic component element mounting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for mounting an electronic component element such as a semiconductor element or a piezoelectric element on a circuit board by face-down bonding.
[0002]
[Prior art]
Conventionally, face-down bonding has been employed for mounting electronic component elements such as semiconductor elements and piezoelectric elements on a circuit board.
[0003]
If such a face-down bonding electronic component element of the mounting rows of it in, secure the circuit board in which a large number of circuit lines is provided on the stage, on one main surface thereof, have a plurality of Au bumps on a lower surface the flip-chip-type electronic component element, Au bumps mounted on the circuit board in the so that to contact the connection pads of the corresponding circuit wiring to Rutotomoni, the electronic component element in the bonding head to the circuit board side pressed, heat or ultrasonic vibration is applied to the Au bump in this state, mounting of the electronic component element is carried out by Rukoto to thermocompression bonding Au bumps to the connection pads.
[0004]
Further, in the conventional mounting process described above, after having taken out a plurality of circuit boards that are placed on the carrier one by one by using a vacuum suction or the like, which was fixed on the stage, mounting of the electronic component element After the work was completed, the circuit board was returned to the carrier again and transferred to the next process.
[0005]
[Problems to be solved by the invention]
By the way, in the conventional mounting method described above, a vacuum suction device is used for fixing the circuit board, and in order to cope with the recent miniaturization of the circuit board, the size of the suction hole provided on the support surface is reduced. It is necessary to design a small hole according to the size of the circuit board.
[0006]
However, if the suction hole of the vacuum suction device is reduced, the suction force will be significantly reduced, making it difficult to obtain the suction force necessary to firmly fix the circuit board. when applying ultrasonic vibration or the like during thermocompression bonding, misaligned between the electronic component element and the circuit board due to vibration, had the disadvantage of Rukoto becomes impossible to satisfactorily bond the Au bump .
[0007]
Therefore in order to solve the above drawbacks, when mounting electronic component devices, it has been proposed to press the one main surface of the circuit board by a bonding head and pressing of example mechanism with electronic component element.
[0008]
However, when the circuit board and the electronic component element are pressed at the same time, positional displacement may occur between the circuit board and the electronic component element due to an impact or the like when pressing these members. Since it is also applied to the circuit board, the amount of displacement between the circuit board and the electronic component element gradually expands due to ultrasonic vibration during the thermocompression bonding operation, and eventually the Au bump is accurately bonded to the connection pad. drawback to Rukoto is impossible is induced.
[0009]
Also with the miniaturization of recent electronic devices, have no longer to be controlled in a very precise bonding accuracy has been required, higher accuracy the positional relationship between the bonding head and the press of example jig for its ing.
[0010]
Further, in the conventional mounting method described above, the circuit boards are taken out from the carrier one by one and the electronic component elements are mounted, so that the working efficiency is extremely poor and it is difficult to improve the productivity of the electronic device. It was.
[0011]
The present invention has been made in view of the above drawbacks, and its object is capable you to satisfactorily bond the Au bump of the electronic component element to the connection pads of the circuit board, and the working efficiency and productivity Another object of the present invention is to provide a method for mounting an electronic component element that is superior to the above.
[0012]
[Means for Solving the Problems]
According to the electronic component element mounting method of the present invention, the circuit board partitioned into the mounting area and the non-mounting area on which the electronic component element is placed is individually accommodated in a plurality of recesses provided on one main surface of the carrier. a step you placed on the stage Te, a step of pressing down the non-mounting region of the upper surface of the circuit board with a press of example jig, remain to press said circuit board by the pressing jig, It said circuit board mounted on the mounting region to Rutotomoni holding an electronic component element having an Au bump on the lower surface at the bonding head, Au of the electronic component said electronic component element a top while pressing by the bonding head device the mounting method of the electronic component device comprising the steps you thermocompression bonding the Au bump to the connection pads of the circuit board by applying heat to the bumps, communicates with the outside of the vacuum pump on the bottom of the recess Suction holes are provided Rutotomoni, vacuum suction the circuit board on the bottom surface of the recess by mounting the suction on the hole, upon thermocompression bonding of the Au bumps, and the said bonding head and the push of example jig to the non-contact state and is characterized that you applying ultrasonic vibration from the bonding head relative to the Au bump.
[0013]
The mounting method of the electronic component device of the present invention having the above structure, the which the bonding head and the press of example jig mechanically coupled and, upon mounting of the electronic component element, the push of example Osamu during ingredients from the start of the lowering operation until the start of pressing of the circuit board top surface, the bonding head and the press of example also downward movement of the jig to perform in conjunction Rutotomoni, the push of example jig after There has started the pressing of said circuit board upper surface is the electronic component device by continued downward movement only of the bonding head which is characterized and placed to Turkey on the circuit board.
[0014]
The mounting method of the electronic component device of the present invention, in the above-mentioned respective structures, to set independently and the pressing force of the bonding head against the pressing force of the pressing of example jig for said circuit board and the electronic component element It is characterized by this.
[0015]
The mounting method of the electronic component device of the present invention, in the above configuration, pressing the said when to mount the electronic component device held by the bonding head on the circuit board holding jig of the circuit board top surface is characterized in that the Ru said push of example jig and said to delay than when to start and control the operation of the bonding head is interlocked.
[0016]
According to the mounting method of the present invention, after the non-mounting region of the circuit board is first pressed with a press of example jig, the electronic component element because it has to be mounted in the mounting area of the circuit board, Au electronic component element When thermobonding the bump to the connection pad, the circuit board can be fixed firmly and firmly to effectively prevent the positional deviation between the circuit board and the electronic component element. Can be bonded well.
According to the mounting method of the present invention, upon thermocompression bonding of Au bumps, when to apply the ultrasonic vibration from the bonding head relative to the Au bump, the circuit board - a large misalignment will occur between the electronic component element without Rukoto can it to efficiently joined in a short time Au bump to the connection pads.
[0017]
Further, according to the mounting method of the present invention, the bonding head and the press of example jig mechanically by connecting, in conjunction partially vertical movement therebetween due to the mounting of the electronic component element by the row of Migihitsuji , the bonding head and pressing of example the relative position control of the tool accurately, yet will be able to line a Ukoto speed, precision without having to decrease the working efficiency even when using a small circuit board in secure bonding of the row Ukoto becomes possible.
[0018]
Still further according to the mounting method of the present invention, by enabling independently setting a pressing force of the bonding head against the pressing force and the electronic component element of the push of example jig with respect to the circuit board, the circuit board and the electronic component element On the other hand, a pressing force having a strength suitable for fixing the circuit board and thermocompression bonding of the Au bumps can be applied. Therefore, a case of utilizing the ultrasonic vibration to the thermocompression bonding of Au bumps also can adjust the pressing force of the push of example jig fixing strength required of the circuit board, the work of bonding There is also an advantage that it can be made good.
[0019]
According to still further implementation of the present invention, it has to be delayed than when to press the circuit board by the when to place the electronic component device held by the bonding head on the circuit board press of example jig from without having to generate positional deviation of the circuit board, the electronic component element can be reliably placed on the predetermined position of the circuit board.
[0020]
Still further according to the mounting method of the present invention, in the state in which housing the circuit board in the recess of the carrier, by mounting the electronic component element on a circuit board, it very efficiently rows mounting operation of the electronic component element Will be able to.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view of an electronic device manufactured by the mounting method of the present invention, wherein 1 is a circuit board, 3 is a connection pad, 4 is an electronic component element, and 5 is an Au bump.
[0022]
The circuit board 1 is formed in a rectangular shape by a ceramic material, a glass-ceramic material, or the like, and a rectangular shape for accommodating an electronic component element 4 to be described later is provided on the upper surface of the circuit board 1. A frame 2 having a shape is integrally attached along the outer periphery of the circuit board 1.
[0023]
Circuit wirings and via holes (not shown) are provided in a predetermined pattern on the upper surface and inside of the circuit board 1 and the frame body 2, and an electronic component is disposed on the upper surface of the circuit board 1 located inside the frame body 2. A plurality of connection pads 3 to which the Au bumps 5 of the element 4 are thermocompression-bonded are provided.
[0024]
The circuit board 1 has one main surface (upper surface) partitioned into a mounting region in which the electronic component element 4 is mounted and a region other than that (non-mounting region). 2 and the electronic component element 4 and the like. When the circuit board 1 is mounted on an external wiring board such as a mother board, the circuit wiring of the circuit board 1 is electrically connected to a wiring conductor such as the mother board on the other main surface (lower surface) of the circuit board 1 . A terminal electrode (not shown) is provided.
[0025]
When the circuit board 1 is made of a glass-ceramic material, an insulating ceramic material such as cristobalite, quartz, corundum (α-alumina), mullite, cordierite or the like as a ceramic component, MgTiO ₃ , CaTiO ₃ , BaTiO ₃ , TiO ₂ or the like is used. Dielectric ceramic materials, magnetic ceramic materials such as Ni—Zn ferrite, Mn—Zn ferrite, etc., and glass components include B ₂ O ₃ , SiO ₂ , Al ₂ O ₃ , ZnO, alkaline earth oxides A glass frit is used, and a plurality of layers of a predetermined ceramic green sheet obtained by adding and mixing an organic solvent or the like to these ceramic materials or glass materials are laminated, press-molded, and fired at a higher temperature. As a result, the circuit board 1 and the frame 2 are integrally formed.
[0026]
Further, the circuit wiring and via holes provided on the upper surface and inside of the circuit board 1 and the frame 2 are through holes previously provided in the ceramic green sheets or between the ceramic green sheets when the circuit board 1 is formed. A conductive material containing, for example, a metal such as Ag, W, Ni, Au, or the like is interposed or filled therein, and these are fired at the same time as firing the ceramic green sheet.
[0027]
The thickness of the ceramic green sheet is set to 20 μm to 300 μm, for example, the thickness of the circuit wiring provided on the circuit board 1 or the like is set to 5 μm to 25 μm, for example, and the diameter of the via hole conductor filled in the via hole is 50 μm It is set to ˜300 μm.
[0028]
An electronic component element 4 is mounted on the inner surface of the frame 2 on one main surface of the circuit board 1 described above.
[0029]
As the electronic component element 4, an electronic component element such as a semiconductor element, a piezoelectric element, a filter, or a capacitor is used. On the lower surface of the electronic component element 4, gold (Au) or a metal mainly composed of gold is used. A plurality of Au bumps 5 are formed so as to form a substantially spherical shape.
[0030]
Such an electronic component element 4 is generally called a flip chip, and conventionally known face-down bonding, that is, a plurality of Au bumps 5 provided on the lower surface of the electronic component element 4 correspond to the circuit board 1. individually they are thermally bonded to the connection pads 3 is mounted on a predetermined position on the circuit board 1 by Rukoto be joined.
[0031]
The electronic device described above functions as an electronic device by being mounted on an external wiring board such as a mother board and being incorporated in an electronic device such as a mobile phone or a personal computer.
[0032]
Next, a method of mounting the electronic component element 4 of the electronic device described above on the circuit board 1 will be described with reference to FIGS. Incidentally, FIG. 2 is a sectional view of each step for explaining a mounting method according to an embodiment of the present invention, FIG. 3 is a push of example jig and bonding head of the mounting apparatus used for mounting method of the present invention FIG. 4 is a side view of a mounting apparatus used in the mounting method of the present invention.
[0033]
(1) First, as shown in FIG. 2A, a circuit board 1 having a frame 2 attached to one main surface is prepared and placed in a recess 12 of a carrier 11 disposed on a stage 10. you location.
[0034]
As described above, the circuit board 1 has one main surface partitioned into a mounting area where the electronic component element 4 is placed and a non-mounting area where the frame body 2 and the like are attached. Manufactured by the described manufacturing method.
[0035]
On the other hand, the stage 10 is for supporting the carrier 11 on its upper surface, and an Au bump 5 of an electronic component element 4 to be described later is thermocompression bonded to the connection pad 3 of the circuit board 1 in the inside thereof . In order to generate the predetermined thermal energy required for heating, a heater is built in, and the Au bump 5 of the electronic component element 4 is heated at a temperature of, for example, 180 ° C. by such a heater.
[0036]
Carrier 11 you arranged on the stage 10 also is adapted to an electronic component device 4 is accommodated in a recess 12 provided on one main surface thereof (upper surface), the opening of the recess 12 is the circuit The size is slightly larger than that of the substrate 1. Specifically, the size is 0.2 mm larger than the outer shape of the circuit substrate 1 in the vertical direction and the horizontal direction.
[0037]
In this embodiment, a suction hole 20 connected to and communicating with an external vacuum pump or the like is provided on the bottom surface of the concave portion of the carrier 11, and the other main surface of the circuit board 1 (the lower surface in the figure) through this suction hole. The circuit board 1 is temporarily fixed at a predetermined position of the carrier 11 by vacuum suction.
[0038]
(2) Next, as shown in FIG. 2 (b), in press of example jig 13 of the mounting device presses the non-mounting region of the circuit board 1 to the lower (stage 10 side), crimping the electronic element 4 until the work is complete, it maintains this state.
[0039]
The push of example jig 13 is formed so as to form a similar rectangular frame body 2, in its central part, the electronic component element 4 held by the bonding head 14 in the step described later (3) A through hole 13 a for passing in the vertical direction is provided, and the non-mounting area of the circuit board 1, specifically, the upper surface of the frame body 2 is pressed.
[0040]
The load the frame 2 is to receive from the pressing of example jig 13 is set to, for example 1200Gf～2500gf, with such pressing force by the suction force of above and attach the circuit board 1 to a predetermined position in the recess 12 It will be.
[0041]
The press of example jig 13 and the bonding head 14 in such a mounting apparatus is mechanistically linked by a connecting arm 22, a vertical axis by pressing of example jig 13 and the bonding head 14 is a Z-axis driving unit 21 as the direction of vertical motion operates in conjunction part, specifically, between the push of example jig 13 starts to lowering operation to the start of the pressing of the circuit board top surface and the bonding head 14 downward movement of the push of example jig 13 is performed in conjunction with, press of example jig 13 is after the start of the pressing of the circuit board top surface continuously performed only downward movement of the bonding head 14, like this It has become so that you mounted on the circuit board 1 the electronic element 4 through a series of operations.
[0042]
The rows that Ukoto the mounting work of the electronic component device using such a mounting apparatus, accurately the relative position control of the bonding head 14 and the push of example jig 13, moreover to allow rows that Ukoto fast it becomes possible precise and reliable bonding lines of Ukoto without having to decrease the working efficiency even in the case of using the circuit board 1 compact.
[0043]
(3) Next, as shown in FIG. 2 (c), holding the electronic component element 4 by a bonding head 14, placed on the mounting area of the circuit board 1 that secure this by pressing of example mechanism 13 .
[0044]
Wherein the bonding head 14, the electronic component element 4 by the connected to the lower surface to an external vacuum pump and suction holes is provided that communicates, to vacuum suck the electronic component element 4 in such a bonding head 14 that holds the the lower end of the bonding head 14.
[0045]
The bonding head 14 is also vertically movable by the movable, to work with pressing of example jig 13 described above, i.e., a predetermined time has passed from the timing you press the circuit board 1 by pressing of example jig 13 Yes and later controls the lowering operation so placed on the electronic component element 4 a circuit board 1, this time, the electronic component device 4 whereas the circuit board 1 which firmly fixed by pressing of example jig 13 positioning to order Te, so that the alignment of the electronic component element 4 to the circuit board 1 is more accurately performed.
[0046]
Incidentally, the electronic component element 4 has a plurality of Au bumps 5 on the lower surface thereof, the circuit board 1 in the so that to contact these Au bumps 5 and the corresponding connection pads 3 of the circuit board 1 you aligned. The alignment of the electronic component element 4 employs a conventional well-known image recognition technique or the like, it row by Rukoto move the XY-axis driving unit 23 in the XY direction.
[0047]
(4) Next, heat and ultrasonic vibration are applied to the Au bumps 5 of the electronic component element 4 while pressing the upper surface of the electronic component element 4 downward with the bonding head 14, thereby Au of the electronic component element 4. Join the bumps 5 to the connection pads 3 of the circuit board 1.
[0048]
At this time, the magnitude of the load received by the electronic component element 4 from the bonding head 14 is controlled to gradually increase. For example, application of ultrasonic vibration is started when the load on the electronic component element 4 reaches 10 gf. When the load reaches 50 gf, the application of ultrasonic vibration is terminated and the application of the pressing force by the bonding head 14 is canceled.
[0049]
On the other hand, the heat you applied to Au bumps 5 is adapted to be supplied from the heater that has been built into the stage 10, the pressing force and the ultrasonic vibration from such heat and bonding head 14 by simultaneously applying the fed versus the Au bumps 5, you efficiently thermocompression bonding in a short time relative to the connection pads 3 of Au bumps 5 to the circuit board 1.
[0050]
In this case, the circuit board 1 is satisfactorily fixed to a predetermined position on the carrier 11 than before to place the electronic component element 4 with pressing of example jig 13, when you put the electronic component element 4 the impact or Au bumps 5 from that does not occur a large positional deviation between the circuit board 1 electronic component element 4 such as by ultrasonic vibration when you thermocompression bonding, Au connection pads 3 of the bumps 5 of the circuit board 1 can it to satisfactorily joined to.
[0051]
Moreover, in this case, the pressing force of the bonding head 14 against the pressing force and the electronic component device 4 of the press of example jig 13 to the circuit board 1, since you are individually independently set, the circuit board 1 and A pressing force having a strength suitable for each fixing can be applied to the electronic component element 4. Therefore, even when ultrasonic vibration is applied to the circuit board 1 as in the present embodiment. If the pressing force is adjusted to an optimum strength by increasing the pressing force on the circuit board 1, misalignment between the circuit board 1 and the electronic component element 4 can be surely prevented, and bonding workability is improved. Can be made good.
[0052]
Further, where the one main surface of the career 11 (upper surface) is formed with a plurality of recesses 12 as shown in FIG. 5, a plurality of circuit board 1 is housed in the recess 12 of the career 11 are transferred to the stage 10 in a state, thereafter, it has become so that to mount the electronic component device 4 on the upper surface of the circuit board 1 arranged on the carrier 11. In this case, transfer defects hardly occur and the efficiency of bonding work can be improved.
[0053]
It should be noted that the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made without departing from the scope of the present invention.
[0054]
Moreover, you may make it seal the upper part of the frame 2 attached to one main surface of the circuit board 1 with the resin material or a cover body in the above-mentioned embodiment.
[0055]
Further although in the above-described embodiment was integrally attached to so that the frame body 2 on one main surface of the circuit board 1 for housing the electronic component element 4 inside, nonexistent circuit board of the frame 2 Even when the electronic component element is mounted thereon, the same effects as those of the above-described embodiment can be obtained.
[0056]
【The invention's effect】
According to the mounting method of the present invention, after the non-mounting region of the circuit board is first pressed with a press of example jig, the electronic component element because it has to be mounted in the mounting area of the circuit board, Au electronic component element When thermobonding the bump to the connection pad, the circuit board can be fixed firmly and firmly to effectively prevent the positional deviation between the circuit board and the electronic component element. Can be bonded well.
According to the mounting method of the present invention, upon thermocompression bonding of Au bumps, when to apply the ultrasonic vibration from the bonding head relative to the Au bump, the circuit board - a large misalignment will occur between the electronic component element without Rukoto can it to efficiently joined in a short time Au bump to the connection pads.
[0057]
Further, according to the mounting method of the present invention, the bonding head and the press of example jig mechanically by connecting, in conjunction partially vertical movement therebetween due to the mounting of the electronic component element by the row of Migihitsuji , the bonding head and pressing of example the relative position control of the tool accurately, yet will be able to line a Ukoto speed, precision without having to decrease the working efficiency even when using a small circuit board in secure bonding of the row Ukoto becomes possible.
[0058]
Still further according to the mounting method of the present invention, by enabling independently setting a pressing force of the bonding head against the pressing force and the electronic component element of the push of example jig with respect to the circuit board, the circuit board and the electronic component element On the other hand, a pressing force having a strength suitable for fixing the circuit board and thermocompression bonding of the Au bump can be applied. Therefore, a case of utilizing the ultrasonic vibration to the thermocompression bonding of Au bumps also can adjust the pressing force of the push of example jig fixing strength required of the circuit board, the work of bonding There is also an advantage that it can be made good.
[0059]
According still further to the mounting method of the present invention, it has to be delayed than when to press the circuit board by the timing electronic component device held by the bonding head you placed on the circuit board press of example jig from without having to generate positional deviation of the circuit board, the electronic component element can be reliably placed on the predetermined position of the circuit board.
[0060]
Still further according to the mounting method of the present invention, in the state in which housing the circuit board in the recess of the carrier, by mounting the electronic component element on a circuit board, it very efficiently rows mounting operation of the electronic component element Will be able to.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an electronic device manufactured by a mounting method of the present invention.
FIGS. 2A to 2D are cross-sectional views for each process for explaining a mounting method according to an embodiment of the present invention. FIGS.
3 is a plan view showing the positional relationship between the press of example jig and bonding head of the mounting apparatus is used to implement the method of the present invention.
FIG. 4 is a diagram showing a configuration of a mounting apparatus used in the mounting method of the present invention.
FIG. 5 is an external perspective view of a carrier used in the mounting method of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Circuit board 2 ... Frame 3 ... Connection pad 4 ... Electronic component element 5 ... Au bump 10 ... Stage 11 ... Carrier 12 ... Recess 13 ... press of example jig 14 ... bonding head 21 ... Z-axis driving unit 22 ... connecting arm 23 ... XY drive unit

Claims (4)

A step you placed on the stage by individually housed electronic element more in the recess provided with a circuit board which is divided into one main surface of the carrier to the mounting region is placed and a non-mounting region,
A step of pressing down the non-mounting region of the upper surface of the circuit board with a press of example jig,
Remain to press said circuit board by the pressing jig, the circuit board mounted on the mounting region to Rutotomoni holding an electronic component element having an Au bump on the lower surface at the bonding head, the electronic component element process and you thermocompression bonding the Au bumps by applying heat to the Au bump of the electronic component device while pressing by the bonding head top surface connection pads of the circuit board
A method for mounting an electronic component element including:
While providing a suction hole that communicates with an external vacuum pump part on the bottom surface of the recess, the circuit board is placed on the suction hole to vacuum-suck to the bottom surface of the recess,
Upon thermal bonding of the Au bump, while the said bonding head and the push of example jig in a non-contact, electron characterized that you applying ultrasonic vibration from the bonding head relative to the Au bump Component element mounting method. Wherein and the bonding head and the press of example jig mechanically coupled and, upon mounting of the electronic component element, the push of example jig pressing the circuit board top surface from the start of the lowering operation until the start, the bonding head and the press of example also downward movement of the jig to perform in conjunction Rutotomoni, after the pressing of example jig starts to press the circuit board top face, of the bonding head mounting method of the electronic component device according to claim 1, lowering operation only by continuation characterized and placed to Turkey the electronic component element on the circuit board. Electronic component according to claim 1 or claim 2, characterized in that you set independently and the pressing force of the bonding head pressing force of the pressing of example jig for said circuit board and for the electronic component element Device mounting method. The push of example jig and to delay than the timing said held by the bonding head electronic component wherein the timing you placed on the circuit board element pressing jig you start the pressing of the circuit board top surface mounting method of the electronic component device according to any one of claims 1 to 3, characterized in that Ru is interlocked to control the operation of the bonding head.

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