JP6151601B2 - Mounting device - Google Patents

Description

  The present invention relates to a mounting apparatus for mounting a chip component on a substrate on which a sealing resin is previously formed.

  One method of flip chip mounting in which chip components such as semiconductor chips are mounted on a substrate is a method in which a liquid resin is applied to the substrate or a film-like resin is applied and then the chip components are heated and bonded by a thermocompression bonding tool. There is a way. This mounting method has the merit that the substrate and the chip component can be bonded together and the sealing resin can be cured at once. However, the resin protruding from the chip component may contaminate the thermocompression bonding tool. For this reason, a method is known in which a film member is sandwiched between a thermocompression bonding tool and a chip component, and the film member is updated each time the chip components are sequentially mounted. In this method, since the chip component needs to be sucked and held by the thermocompression bonding tool via the film member, the film member at a position facing the chip suction hole of the thermocompression bonding tool needs to have a vent hole. is there.

  For this purpose, Patent Document 1 describes a mounting apparatus provided with a punching means for forming a vent hole in a film member at a position facing a chip suction hole of a thermocompression bonding tool. Further, Patent Document 2 describes a mounting device that uses a film member having a vent hole in advance and performs alignment so that the vent hole faces a suction hole of a thermocompression bonding chip.

Japanese Patent Laid-Open No. 2003-7771 JP 2006-66767 A

  By the way, in the mounting apparatus as described in Patent Document 1, when the thermocompression bonding tool is at a high temperature when the film member is updated to form the vent hole, the film member is easily stretched. It becomes difficult to drill. That is, as shown in FIG. 11, even if the needle push-in amount LP is normally penetrated by the needle of the perforating means, the film member does not penetrate and penetrate at a high temperature. For this reason, in order to form a through-hole reliably in a film member, it waits for the temperature of a thermocompression-bonding tool to fall, Then, it perforates. The time for waiting for the temperature of the thermocompression bonding tool to decrease is a loss of tact time of the mounting apparatus, which hinders productivity improvement. On the other hand, in the mounting apparatus as in Patent Document 2, it takes time to align the chip suction hole of the thermocompression bonding tool and the air hole of the film member every time the film member is updated. Furthermore, it may take time to align the film member due to heat deformation.

  Therefore, an object of the present invention is to provide a mounting apparatus that does not cause a tact time loss of a mounting process as much as possible when forming a vent hole in a film member sandwiched between a thermocompression bonding tool and a chip component.

In order to solve the above problems, the invention according to claim 1 is a mounting apparatus in which the chip component is thermocompression bonded to a substrate by a thermocompression tool that holds the chip component via a heat-resistant film member.
The thermocompression bonding tool has a suction hole for sucking and holding the chip component,
In order to adsorb the chip component to the thermocompression bonding tool through the film member, the mounting device includes a punching unit that forms a vent hole by pushing a needle into the film member at a position facing the adsorption hole. And
If the maximum elongation of the film member is CEmax,
The pressing amount LP (unit: mm) of the needle from the surface of the film member is 0.5 × D × (CEmax + 1) <LP <0.8 × with respect to the diameter D (unit: mm) of the suction hole. D × (CEmax + 1)
It is the mounting apparatus characterized by being set to the range of.

Invention of Claim 2 is the mounting apparatus of Claim 1, Comprising:
If the maximum elongation of the film member is CEmax,
The pressing amount LP (unit: mm) of the needle from the surface of the film member is 0.55 × D × (CEmax + 1) ≦ LP ≦ 0.7 × with respect to the diameter D (unit: mm) of the suction hole. D × (CEmax + 1)
It is the mounting apparatus characterized by being set to the range of.

Invention of Claim 3 is the mounting apparatus of Claim 1 or Claim 2, Comprising:
Air cooling means for cooling the thermocompression bonding tool, and a temperature sensor for measuring the temperature of the thermocompression bonding tool,
In the process of cooling the thermocompression bonding tool after thermocompression bonding the chip component to the substrate, it has a film member transport mechanism for transporting the film member ,
The mounting device is characterized in that, when the measured value of the temperature of the thermocompression bonding tool is lowered to a predetermined value, the punching means starts operating.

Invention of Claim 4 is the mounting apparatus of Claim 3, Comprising:
Temperature measurements of the thermal pressure bonding tool, wherein the perforation means starts operation, the continuous use heat resistant temperature than 30 ° C. lower temperature of the film member, the range of the film used continuously from 100 ° C. lower heat resistance temperature temperature member It is the mounting apparatus characterized by this.

Invention of Claim 5 is the mounting apparatus in any one of Claims 1-4, Comprising:
A mounting apparatus using a fluororesin for the film member.

Invention of Claim 6 is the mounting apparatus in any one of Claims 1-5, Comprising:
The thermocompression bonding tool includes a plurality of suction holes, and includes a punching unit that simultaneously forms a vent hole in the film member at a position facing each suction hole.

Invention of Claim 7 is the mounting apparatus of Claim 6, Comprising:
Mounting wherein a part of the plurality of suction holes of the thermocompression bonding tool is a through hole communicating with a vacuum exhaust function, and the remaining suction holes are non-through holes connected to the through hole and a groove. Device.

According to the first aspect of the present invention, in the mounting apparatus for thermocompression bonding the chip component to the substrate by a thermocompression tool that holds the chip component via a heat-resistant film member, the thermocompression tool includes the chip component. A suction hole for holding by suction is provided, and in order to suck the chip component to the thermocompression bonding tool through the film member, a needle is pushed into the film member at a position facing the suction hole to form a vent hole. A mounting device provided with punching means to form,
If the maximum value of the elongation rate of the film member is CEmax, the pressing amount LP of the needle from the surface of the film member with respect to the diameter D of the suction hole is set to 0.5 × D × (CEmax + 1) <LP By setting it in the range of <0.8 × D × (CEmax + 1), the air hole can be formed even if the film member is a stretchable material. That is, when a hole is made by pushing a needle into the film member, the film member can be penetrated even if it is easily stretched by receiving heat. For this reason, drilling is possible even when the temperature of the thermocompression bonding tool is high, and the time for waiting for the temperature reduction of the thermocompression bonding tool can be greatly shortened.

  According to the invention of claim 2, the pressing amount LP of the needle from the surface of the film member with respect to the diameter D of the suction hole is 0.55 × D × (CEmax + 1) ≦ LP ≦ 0.7 × D. By setting in the range of × (CEmax + 1), the air pressure hole can be surely formed in the film member at a high temperature of the thermocompression bonding tool, and the thickness of the thermocompression bonding tool is not increased more than necessary. Energy during heating and cooling of the tool can be reduced.

  According to the invention of claim 3, although the film member can be perforated even when the temperature of the thermocompression bonding tool is high, the temperature of the thermocompression bonding tool is lowered to a predetermined temperature in order to prevent the adverse effects caused by high temperature perforation. The drilling is performed from above, and it has a function to measure the temperature of the thermocompression bonding tool and a cooling function. As a result, it is possible to prevent perforation in a state where the temperature is too high, and to shorten the time for lowering to a predetermined temperature.

  According to the invention of claim 4, the temperature at which perforation is started can be determined to a value suitable for the material of the film member.

  According to the invention of claim 5, although it is excellent in heat resistance and adhesion resistance, it is possible to effectively utilize a film member using a fluororesin having a remarkable feature of being easily stretched by receiving heat.

  According to the sixth and seventh aspects of the present invention, the chip component can be securely held by the thermocompression-bonding tool because it is adsorbed at a plurality of locations even through the film member.

It is a figure which shows the structure of the mounting apparatus which is embodiment of this invention. It is a figure for demonstrating the periphery part of the thermocompression-bonding tool of the mounting apparatus of FIG. It is a figure for demonstrating operation | movement of the mounting apparatus which is embodiment of this invention. It is a figure for demonstrating operation | movement of the mounting apparatus which is embodiment of this invention. It is a figure for demonstrating operation | movement of the mounting apparatus which is embodiment of this invention. It is a figure for demonstrating operation | movement of the mounting apparatus which is embodiment of this invention. It is a figure for demonstrating operation | movement of the mounting apparatus which is embodiment of this invention. It is a figure for demonstrating operation | movement of the mounting apparatus which is embodiment of this invention. It is a figure explaining the pushing amount for making a hole in a film member from a geometrical viewpoint. It is a figure which shows the example which does not have a hole in a film member by the pushing amount by geometric examination. It is a figure explaining that a hole is hard to be vacant when a film member is high temperature.

DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention will be described with reference to the drawings.
First, FIGS. 1-8 is a figure which shows the structure and operation | movement of the mounting apparatus 1 which is one Embodiment of this invention. FIG. 1 shows a process for forming a vent hole in a tape-like film member 14 when a chip component 11 shown in FIG. 3 to be described later is flip-chip bonded to a substrate 12 coated with a liquid resin 13. ing. Here, as the film member 14, a material having excellent heat resistance and excellent adhesion to chip parts and the like is selected, and polytetrafluoroethylene (PTFE), tetrafluoroethylene A fluororesin such as a perfluoroalkyl vinyl ether copolymer (PFA) is preferred. Further, the thickness is preferably about 20 to 50 μm in consideration of the thermal conductivity to the chip component while maintaining the mechanical strength.

  In FIG. 1, the bonding head 2 includes a thermocompression bonding tool 21, a heat insulating block 22, a holder 23, a head body 24, and a pressure mechanism 25. The film member transport mechanism 3 for transporting the film member 14 is configured by attaching a winding roll 32, a winding roll 33, and the like to a transport system frame 31. Further, the substrate 12 is held by suction by the substrate stage 51, and the position of the substrate can be moved in the XY and θ directions by a substrate stage moving means (not shown).

  The details of the punching means 4 are shown in FIG. 2 including the relationship with the periphery of the thermocompression bonding tool 21. In FIG. 2, the thermocompression bonding tool 21 is composed of an attachment tool 21A for attracting and holding the chip component 11, a heater 21H, and a temperature sensor 21T. The thermocompression bonding tool constituted by the attachment tool 21A, the heater 21H, and the temperature sensor 21T is sucked and held by the heat insulating block 22 so that it can be exchanged according to the shape of the chip part 11 to be sucked and held. Although a vacuum system for adsorbing the thermocompression bonding tool 21 is not shown, it is different from a vacuum system for adsorbing and holding a chip component 11 described later.

  A plurality of suction holes 20 are formed in the attachment tool 21A. The suction holes 20 are connected to a through suction hole 20H that is directly connected to a vacuum source (not shown), and through the through suction hole 20H and the groove 20C. The non-penetrating suction hole 20B is formed. The number of suction holes 20 is selected in the range of 9 to 25, although it depends on the size of the chip component 11 to be sucked and held. The number of needles 41 constituting the punching means 4 is the same as that of the suction holes 20. Further, when cooling the attachment tool 21A, the heater 21H is not only turned off, but also has a function of circulating external air through the air flow path 200.

  When forming the air hole in the film member 14, after the suction hole 20 and the needle 41 are aligned, the perforating means 4 is moved upward so that the needle 41 pushes the film member 14 in close contact with the surface of the attachment tool 21A. The film member 14 is penetrated by moving in the direction (Z direction) or by moving the engagement member including the attachment tool 21A downward. How to push the needle 41 at that time will be described later.

  After the air holes are formed in the film member 14, as shown in FIG. 3, the chip component 11 is arranged immediately below the bonding tool 2 by the chip chip component conveying tool 61, and is attached to the thermocompression bonding tool 21 via the film member 14. Adsorbed and held. Thereafter, as shown in FIG. 4, the two-view camera 71 aligns the chip component 11 and the substrate 12. At the time of alignment, the substrate stage 51 that holds the substrate 12 by suction moves in the XY direction and the θ direction and is adjusted. When the alignment in FIG. 4 is completed, the bonding head 2 is lowered together with the film member transport mechanism 3 as shown in FIGS. 5 and 6, and the flip chip bonding is performed. In the joining step shown in FIG. 6, the heater 21H constituting the thermocompression bonding tool 21 is heated, and the heat is transmitted to the joining surface between the chip component 11 and the substrate 12, and the resin 13 that has been liquid is heat-cured, Joining is complete. In this process, the heater 21 stops the temperature rise, and after joining is completed, external air is introduced into the air flow path 200 shown in FIG. 2 to start cooling the attachment tool 21A.

  When the joining is completed, as shown in FIG. 7, the suction of the chip 11 by the attachment tool 21A is released, and the film member transport mechanism 3 and the bonding head 2 are raised. At this stage, the relative positions of the bonding head 2 and the film member transport mechanism 3 are different from those before, and a gap is generated between the surface of the attachment tool 21 </ b> A and the film member 14. In this state, the film member 14 sandwiched between the chip component 11 and the attachment tool 21A moves to the take-up roll 33 side, and a new film member 14 is supplied from the unwind roll 32 side to attach the attachment tool 21A. It is placed immediately below. When the new film member 14 is disposed immediately below the attachment tool 21A, the relative positions of the bonding head 2 and the punching means 4 are adjusted so that the film member 14 can be sucked and held by the attachment tool 21A as shown in FIG.

  In this way, the film member 14 is updated, and the punching means 4 is disposed immediately below the attachment tool 21A, and the position where the chip component is mounted next by moving the substrate is disposed below the bonding head. On the other hand, when the attachment tool 21A continues to be cooled and the temperature measured by the temperature sensor 21T falls to a predetermined temperature range, the needle 41 of the punching means 4 is pushed into the film member 14 to form a vent hole.

  The above is description of the structure and operation | movement of the mounting apparatus 1 in embodiment of this invention. Next, conditions for reliably forming a vent hole in the film member 14 facing the suction hole 20 of the attachment tool 21A by the mounting apparatus 1 will be described.

  First, a simple geometric study will be described with reference to FIG. In this examination, it is assumed that the thickness of the film member 14 is negligible with respect to the suction hole 20. Further, the maximum value of the elongation rate CE of the film member is defined as CEmax. The elongation rate mentioned here is (length of stretched) / (original length before stretched). When stretched twice the original length, “length of stretched” Is the same as the “original length before being stretched”, so the stretch rate is 1. Therefore, when the maximum value of the elongation rate is CEmax, there is a possibility that the length becomes (CEmax + 1) times the original length. Therefore, when the diameter of the suction hole is D, FIG. 9A shows a case where the film member 14 is pushed in with a rod-shaped one having a diameter D, but the push-in amount is (CEmax × D / 2) and the elongation is increased. Reaches the upper limit. FIG. 9B shows the case where the film member 14 is pushed in with a rod whose diameter is negligible compared to D, but the length of the two sides of the isosceles triangle is (CEmax + 1) × D / 2. The elongation of the film member reaches the upper limit before the pressing amount reaches (CEmax + 1) × D / 2. Further, since the film member actually extends in the two-dimensional direction, it cannot be considered that the film member extends to the upper limit of elongation in both two-dimensional directions. Therefore, in both cases of FIG. 9A and FIG. 9B, if the push-in amount is (CEmax + 1) × D / 2, the upper limit of the elongation of the film member 14 is exceeded, so the hole is surely opened. It is expected that.

  However, even in the case where the pushing amount LP of the needle 41 in FIG. 10 is (CEmax + 1) × D / 2, there are rare cases in which the vent hole is not formed although the frequency is low. The cause of such a phenomenon is considered to be that when the needle 41 is pushed in, the film member 14 around the suction hole 20 extends and enters the suction hole 20.

  For this reason, the pushing amount LP of the needle 41 needs to exceed at least (CEmax + 1) × D / 2, and is preferably 1.1 times or more of (CEmax + 1) × D / 2. On the other hand, in order to increase the pushing amount LP, it is necessary to increase the thickness of the attachment tool 21A in FIG. 2. If the thickness is increased, transmission of heat generated from the heater 21H is hindered. Therefore, it is desirable that the pushing amount LP is less than 1.6 times (CEmax + 1) × D / 2, and preferably 1.4 times or less.

  That is, 0.5 × D × (CEmax + 1) <LP <0.8 × D × (CEmax + 1), and preferably 0.55 × D × (CEmax + 1) ≦ LP ≦ 0.7 × D × (CEmax + 1) ) Is desirable.

  Next, the temperature of the attachment 21A at the time of starting the perforating operation for pushing the needle 41 into the film member 14, but as described above, since the vent hole can be formed even when the elongation rate of the film member 14 is maximum, the film It seemed that it should be below the heat resistance temperature of the member 14. However, it has been found that by continuing the perforation work while the temperature of the film member 14 is high, the composition of the film member 14 is transferred to the needle 41 and laminated, and the laminate hinders the perforation work. Therefore, when the start temperature of the drilling operation was examined, it was found that a laminate was not formed if the temperature was lower by 30 ° C. or more than the heat resistance temperature of the film member 14. As a matter of course, it is possible to further lower the starting temperature of the drilling operation, but if the temperature is lower than 100 ° C., the vent hole can be formed by a method other than the present invention. In addition, although the above-mentioned heat-resistant temperature is a continuous use heat-resistant temperature and may measure the temperature of the film member 14 directly using an optical means etc., this invention is a temperature sensor installed in the thermocompression-bonding tool 21. Instead of the temperature of the film member 14 at a measurement temperature of 21T.

  Nine suction holes 20 were formed as the attachment tool 21A, and each suction hole 20 had a diameter D of 0.5 mm. As the film member 14, Teflon (registered trademark) which is a polytetrafluoroethylene (PTFE) resin having a thickness of 30 μm was used. Since the elongation of Teflon (registered trademark) is 2 to 4 (200% to 400%), CEmax is 4. Further, the heat resistance temperature for continuous use of Teflon (registered trademark) is 260 ° C. At the time of bonding, the attachment tool 21A was heated to 320 ° C. close to the melting point of Teflon (registered trademark) by the heater 21H, and then cooled.

In the course of cooling, the needle 41 was pushed into the film member, and whether or not the air holes could be formed, that is, whether or not the nine suction holes 20 were penetrated was examined. The pushing amount LP of the needle 41 was performed by changing α of α × D × (CEmax + 1).
Example 1
In the premise described above, D × (CEmax + 1) is 0.5 × (4 + 1) = 2.5 (mm), and therefore, when the pushing amount LP = 1.4 (mm) where α = 0.56. Table 1 shows the results of examining the relationship between the temperature of the attachment tool 21A and the pressing amount LP of the needle 41. In Table 1, the numerical value described in parentheses on the right side of “Attachment tool temperature” is the time required for the attachment tool after bonding to drop to each temperature. At 230 ° C., the cooling time of the attachment tool is 1.1 sec, but it can be seen that vent holes can be opened at all positions facing the suction holes 20.
(Example 2)
The same result as in Example 1 was obtained except that the pushing amount LP = 1.7 (mm) and α = 0.68, and the same result as in Example 1 was obtained.

(Comparative Example 1)
This is the result when the pushing amount LP = 0.9 and α = 0.36, and the upper limit temperature at which the vent holes can be opened at all positions facing the suction holes 20 is as low as 150 ° C. The time required for the attachment tool to drop to this temperature was 2.7 sec, which was 1.6 sec longer than those in Examples 1 and 2.

  As described above, in Example 1 and Example 2, the attachment cooling time is shortened by 1.6 sec as compared with Comparative Example 1, but in this example, the tact time for mounting one chip component is reduced. Since the time other than the attachment cooling is less than 10 seconds, the tact time can be shortened by 10% or more, which proves effective in productivity.

  INDUSTRIAL APPLICABILITY The present invention is suitable for a mounting apparatus that performs bonding by sandwiching a film member between a thermocompression bonding tool and a chip component, and particularly for a mounting apparatus that needs to form air holes in the film member in order to suck and hold the chip component. is there.

DESCRIPTION OF SYMBOLS 1 Mounting apparatus 2 Bonding head 3 Film member conveyance mechanism 4 Perforation means 11 Chip component 12 Substrate 13 Resin 14 Film member 20 Suction hole 20B Non-through suction hole 20C Groove 20H Through suction hole 21 Thermocompression bonding tool 21A Attachment tool 21H Heater 21T Temperature sensor 22 Heat insulation block 23 Holder 24 Head body 25 Pressure mechanism 31 Transport system frame 32 Unwinding roll 33 Winding roll 41 Needle 51 Substrate stage 61 Chip component transport tool 71 Two-field camera 200 Air flow path

Claims (7)

In a mounting apparatus for thermocompression bonding the chip component to a substrate by a thermocompression bonding tool that holds the chip component via a heat-resistant film member,
The thermocompression bonding tool has a suction hole for sucking and holding the chip component,
In order to adsorb the chip component to the thermocompression bonding tool through the film member, the mounting device includes a punching unit that forms a vent hole by pushing a needle into the film member at a position facing the adsorption hole. And
If the maximum elongation of the film member is CEmax,
The pressing amount LP (unit: mm) of the needle from the surface of the film member is 0.5 × D × (CEmax + 1) <LP <0.8 × with respect to the diameter D (unit: mm) of the suction hole. D × (CEmax + 1)
A mounting apparatus characterized by being set in a range of The mounting apparatus according to claim 1,
If the maximum elongation of the film member is CEmax,
The pressing amount LP (unit: mm) of the needle from the surface of the film member is 0.55 × D × (CEmax + 1) ≦ LP ≦ 0.7 × with respect to the diameter D (unit: mm) of the suction hole. D × (CEmax + 1)
A mounting apparatus characterized by being set in a range of The mounting apparatus according to claim 1 or 2,
Air cooling means for cooling the thermocompression bonding tool, and a temperature sensor for measuring the temperature of the thermocompression bonding tool,
In the process of cooling the thermocompression bonding tool after thermocompression bonding the chip component to the substrate, it has a film member transport mechanism for transporting the film member ,
The mounting apparatus, wherein the punching means starts operating when a measured value of the temperature of the thermocompression bonding tool is lowered to a predetermined value. The mounting apparatus according to claim 3,
Temperature measurements of the thermal pressure bonding tool, wherein the perforation means starts operation, the continuous use heat resistant temperature than 30 ° C. lower temperature of the film member, the range of the film used continuously from 100 ° C. lower heat resistance temperature temperature member A mounting apparatus characterized by that. The mounting apparatus according to any one of claims 1 to 4,
A mounting apparatus using a fluororesin for the film member. The mounting device according to any one of claims 1 to 5,
A mounting apparatus comprising: a thermo-compression tool having a plurality of suction holes, and a perforating means for simultaneously forming a vent hole in the film member at a position facing each suction hole. The mounting apparatus according to claim 6,
Mounting wherein a part of the plurality of suction holes of the thermocompression bonding tool is a through hole communicating with a vacuum exhaust function, and the remaining suction holes are non-through holes connected to the through hole and a groove. apparatus.