JP6252687B2 - Manufacturing method of resin multilayer substrate - Google Patents

Description

  The present invention relates to a method for producing a resin multilayer substrate.

  For example, in Japanese Patent Application Laid-Open No. 2014-120722 (Patent Document 1), in order to obtain a light emitting device, predetermined components are mounted on a substrate in a state of a collective substrate, and the surface from the substrate surface to the side surfaces of these components is buried. After the reflection resin is disposed on the substrate, the reflection resin and the substrate are collectively cut along a predetermined cutting line. In this way, separation into individual products is performed. This separation process is also called “dividing into pieces”.

JP, 2014-120722, A

  Even in the method of manufacturing a light emitting device as described in Patent Document 1, it is considered that when chips are separated from the state of the collective substrate, material chips are generated. Not considered. Even when the singulation is performed using a blade or by laser processing, chips of material are scattered around the periphery.

  It is considered that the chips scattered around the individual pieces are scattered on the upper surface of individual products as a powdery object. If the chips are so scattered, the appearance of the product will deteriorate. Further, if chips overlap a positioning mark or the like provided in advance in the product, automatic positioning using this positioning mark may not be performed correctly. In addition, chips that have already been scattered on the surface of the product may re-float and scatter due to some impact and land at other undesired locations. If chips adhere to other parts of the product, the operation and characteristics of the other parts may be hindered.

  Then, an object of this invention is to provide the manufacturing method of the resin multilayer substrate which can reduce the inconvenience resulting from the chip which arises in the case of individualization and is scattered.

  In order to achieve the above object, a method for producing a resin multilayer substrate according to the present invention is a method of laminating a plurality of base materials mainly composed of a thermoplastic resin at a temperature equal to or higher than the softening temperature of the thermoplastic resin. A step of heating and pressing in a state where pressure is applied to obtain a collective substrate, a step of cutting out the individual substrate from the collective substrate, and a step of reusing the individual substrate above the softening temperature of the thermoplastic resin. Heating.

  According to the present invention, since the scattered chips are softened after being softened, they are integrated into an individual substrate, and as a result, it is possible to reduce inconveniences caused by scattered chips generated during the separation. Can do.

It is a flowchart of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 1st process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 2nd process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 3rd process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 4th process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 5th process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 6th process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 7th process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 8th process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is explanatory drawing of the 9th process of the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention. It is an enlarged view of the Z section in FIG. It is an enlarged view of the Z part after finishing the process of reheating above the softening temperature of a thermoplastic resin. It is explanatory drawing of the process performed with the manufacturing method of the resin multilayer substrate in Embodiment 2 based on this invention. It is an enlarged view of the upper surface edge part vicinity of the separate substrate in the middle step of the manufacturing method of the resin multilayer substrate in Embodiment 2 based on this invention. It is explanatory drawing of a mode that an adhesive sheet is pulled in the middle step of the manufacturing method of the resin multilayer substrate in Embodiment 3 based on this invention. It is a flowchart of the manufacturing method of the resin multilayer substrate in Embodiment 4 based on this invention. It is sectional drawing of the mode after mounting components by the manufacturing method of the resin multilayer substrate in Embodiment 4 based on this invention.

(Embodiment 1)
With reference to FIGS. 1-12, the manufacturing method of the resin multilayer substrate in Embodiment 1 based on this invention is demonstrated. FIG. 1 shows a flowchart of a method for manufacturing a resin multilayer substrate in the present embodiment.

  The method for producing a resin multilayer substrate in the present embodiment is a state in which pressure is applied at a temperature equal to or higher than the softening temperature of the thermoplastic resin to a laminate of a plurality of base materials mainly composed of a thermoplastic resin. Step S1 to obtain a collective substrate by heating and pressing in step S1, Step S2 of cutting out the individual substrate from the collective substrate, and Step S3 of reheating the individual substrate above the softening temperature of the thermoplastic resin Including.

  This will be described in more detail below. First, prior to step S <b> 1, a “layer obtained by laminating a plurality of base materials mainly composed of a thermoplastic resin” is prepared. The base material is not limited to a sheet shape, but may be any shape, but a sheet shape, that is, a resin sheet is usually used.

  First, a resin sheet 12 with a conductor foil as shown in FIG. 2 is prepared. The resin sheet with conductor foil 12 is a sheet having a structure in which the conductor foil 17 is attached to one surface of the resin layer 2. The resin layer 2 is, for example, a thermoplastic resin. In the present embodiment, the resin layer 2 is mainly made of, for example, a thermoplastic type PI (polyimide). The material of the resin layer 2 may be PEEK (polyether ether ketone), PEI (polyether imide), PPS (poniphenylene sulfide), LCP (liquid crystal polymer), etc. in addition to the thermoplastic PI. Good. The conductor foil 17 is a metal foil made of Cu, for example. In the present embodiment, a metal foil having a thickness of 18 μm is used as the conductor foil 17. The material of the conductor foil 17 may be Ag, Al, SUS, Ni, Au other than Cu, or may be an alloy of two or more different metals selected from these metals. In the present embodiment, the conductor foil 17 has a thickness of 18 μm, but the conductor foil 17 has a thickness of, for example, about 3 μm to 40 μm. That is, the conductor foil 17 may be of a thickness that allows circuit formation.

  When preparing the resin sheet 12 with a conductive foil, a plurality of resin sheets 12 with a conductive foil may be prepared, and then individually as a plurality of resin sheets in one sheet of the resin sheet 12 with a conductive foil. A region in which an area to be cut out is set may be prepared.

  Next, the conductive foil 17 is patterned by a method such as photolithography. As shown in FIG. 3, the remaining part of the conductor foil 17 becomes the conductor pattern 7.

  Next, as shown in FIG. 4, the surface of the resin layer 2 opposite to the surface to which the conductor pattern 7 of the resin sheet 12 with conductor foil adheres is irradiated with a laser beam 13 so as to penetrate the resin layer 2. A via hole 11 is formed in the substrate. The laser beam 13 may be, for example, a carbon dioxide laser beam. The via hole 11 penetrates the resin layer 2 but does not penetrate the conductor pattern 7. Thereafter, smears (not shown) in the via holes 11 are removed as necessary. As the laser beam 13 for forming the via hole 11, it is preferable to use a laser beam that penetrates the resin layer 2 but does not penetrate the conductor foil. In addition, a method other than laser beam irradiation may be employed to form the via hole 11.

  As shown in FIG. 5, the interlayer connection conductor 6 is formed by filling the via hole 11 with a conductive paste by screen printing or the like.

  Here, the conductor pattern 7 is first formed by patterning, then the via hole 11 is formed, and the interlayer connection conductor 6 is formed. However, this order may be reversed. That is, the conductor pattern 7 may be formed by patterning after forming the via hole 11 and forming the interlayer connection conductor 6.

  The conductive paste filled to form the interlayer connection conductor 6 may be composed mainly of silver, but instead may be composed mainly of copper, for example. This conductive paste forms an alloy layer with the metal that is the material of the conductor pattern 7 at the temperature when the laminated resin layer is thermocompression bonded (hereinafter referred to as “thermocompression temperature”). It is preferable that the metal powder contains an appropriate amount. Since this conductive paste contains copper, that is, Cu as a main component for exerting conductivity, this conductive paste includes at least one of Ag, Cu, and Ni in addition to the main component, and Sn, Bi, Zn. It is preferable that at least one of them is included. Thus, the interlayer connection conductor 6 is formed as shown in FIG.

  As shown in FIG. 6, a plurality of substrates are collected. Here, a set of a plurality of base materials is shown as a base material group 19. Each substrate is in the form of a sheet including the resin layer 2. By laminating these base materials, a laminate 20 is obtained as shown in FIG. As step S1, as shown by an arrow 91 in FIG. 8, the laminate 20 is hot-pressed in a state where pressure is applied at a temperature equal to or higher than the softening temperature of the thermoplastic resin. The softening temperature of the thermoplastic resin is, for example, any temperature between 250 ° C. and 260 ° C. The “temperature above the softening temperature” used in the heating press in step S1 is, for example, 270 ° C. The pressure applied for the heating press in step S1 is, for example, 8.4 MPa. The time for this heating press is, for example, 1 hour.

  Thereby, the laminated body 20 is integrated to obtain a collective substrate 22 as shown in FIG. The heating press in the step S1 may be one in which all the substrates are laminated and then heated and pressed together, but each time one or a certain number of layers of the substrates are laminated, Then, a method of repeating the procedure of laminating the substrate of the next one layer or a certain number of layers and heating and pressing again may be used. Alternatively, a method may be used in which a temporary heating press is performed every time one or a certain number of layers of substrates are laminated, and a full-scale heating press is performed after the lamination of all layers of the substrates. .

  Furthermore, a solder resist layer (not shown) may be formed around the conductor pattern 7 exposed on the surface of the collective substrate 22. A plating film (not shown) may be appropriately formed so as to cover the surface of the conductor pattern 7 exposed on the surface of the aggregate substrate 22.

  As step S2, a step of cutting out the individual substrates 24 from the collective substrate 22 is performed. That is, the collective substrate 22 is cut. This cutting may be performed by a cutting tool such as a dicing blade, or by a non-contact method such as laser processing. In the step S2, one or more individual substrates 24 may be cut out from the collective substrate 22. Usually, a large number of individual substrates 24 are cut out from one collective substrate 22. The results of performing step S2 are shown in FIG. Not only is it cut at the center, but the end is also sized by cutting the margin. In FIG. 10, for convenience of explanation, two individual substrates 24 are cut out from one collective substrate 22, but actually, the number is not limited to two, and a larger number of individual substrates 24 may be cut out. . In the example shown in FIG. 10, step S <b> 2 is performed with the collective substrate 22 attached to the surface of the pressure-sensitive adhesive sheet 4, but the use of the pressure-sensitive adhesive sheet 4 is not essential. The collective substrate 22 may be cut as it is without being attached to the adhesive sheet 4. In the example shown in FIG. 10, the aggregate substrate 22 is cut so that the adhesive sheet 4 is not cut in a state where the aggregate substrate 22 is attached to the surface of the adhesive sheet 4. The thing with 24 adhered is obtained.

  When the step S2 is completed, the chips 5 are placed on the upper surface of the individual substrate 24 as shown in FIG. FIG. 11 shows an enlarged view of the Z portion in FIG. The individual substrate 24 has an upper surface 24a and a side surface 24b that newly appears as a result of the cutting performed in step S2. Chips 5 are placed on the end of the upper surface 24a. The chips 5 are scattered when the collective substrate 22 is cut. The chip 5 can be generated both when the cutting in the step S2 is performed by a blade and by laser processing or the like.

  In step S3, the individual substrate 24 is reheated at a temperature equal to or higher than the softening temperature of the thermoplastic resin. As a result, the chips 5 are melted. After the heating is stopped, the chips 5 harden again, but at this point, they are integrated with the upper surface 24a as shown in FIG. In this example, what was originally the chip 5 remains as the protrusion 15 on the upper surface 24a.

  In the present embodiment, since the step S3 of reheating at the softening temperature or higher of the thermoplastic resin is included after the step S2 of cutting out to the individual substrate 24, the scattered chips 5 are softened in the step S3. By re-solidifying after melting, it is integrated with the individual substrate 24 as shown in FIG. The integrated chip 5 no longer moves freely. The chips 5 integrated on the individual substrate 24 in the step S3 may remain as the protrusions 15, but may be almost or completely lost in shape. The protrusion 15 illustrated in FIG. 12 is merely an example, and the chips 5 do not need to remain as the protrusion 15 after step S3.

  According to the present embodiment, it is possible to reduce inconveniences caused by chips that are generated and scattered during singulation.

  Here, the description has been made by paying attention to the chips 5 scattered on the upper surface 24a of the individual substrate 24. However, even if there is chips adhering to the side surface 24b, the chips are similarly melted in the step S3, Since it integrates with 24, the inconvenience resulting from the chip | tip adhering to a side surface can also be reduced.

  In addition, when the time to heat-press in process S1 which obtains an aggregate substrate is set to 1st time T1, it is preferable to heat over 2nd time T2 shorter than 1st time T1 in process S3 to reheat. In the above example, the first time T1 is 1 hour. Since the second time T2 is shorter than the first time T1, for example, it is an arbitrary time within the range of 10 minutes to 20 minutes. By suppressing the reheating in step S3 to the second time T2, it is possible to avoid the individual substrate from being heated excessively. Further, useless heating is eliminated, and the time required for step S3 can be shortened.

(Embodiment 2)
With reference to FIG. 13, the manufacturing method of the resin multilayer substrate in Embodiment 2 based on this invention is demonstrated. The manufacturing method of the resin multilayer substrate in the present embodiment is the same as the manufacturing method described in the first embodiment, but is different in the following points.

  In the method for manufacturing the resin multilayer substrate in the present embodiment, the individual substrate 24 is pressurized as shown in FIG. 13 over at least a part of the heating time in the reheating step S3. In the example shown in FIG. 13, with the plurality of individual substrates 24 fixed to the adhesive sheet 4, these are sandwiched between the molds 31 and 32 and pressed as indicated by an arrow 92. By pressurizing in this way, the vicinity of the upper end portion of the individual substrate 24 becomes flat as shown in FIG.

  In the present embodiment, since the individual substrate 24 is pressurized in the reheating step S3, the scattered chips 5 are softened in the step S3 and crushed in a molten state to be integrated with the upper surface 24a of the individual substrate 24. To do. Therefore, as shown in FIG. 14, there is almost no trace of the chips 5 present on the upper surface 24a.

  According to the present embodiment, it is possible to reliably reduce the inconvenience caused by the chips that are generated and scattered at the time of singulation more than in the case of the first embodiment.

  In addition, when the pressure applied at the time of heat-pressing in the step S1 for obtaining the aggregate substrate 22 is the first pressure P1, when the individual substrate 24 is pressurized in the step S3, the second pressure lower than the first pressure P1. It is preferable to pressurize with P2. If the first pressure P1 is 8.4 MPa, the first pressure P2 may be a pressure of 0.5 MPa or more and 1.0 MPa or less, for example. The purpose of the pressurization in the step S1 is to integrate the whole of the plurality of base materials, but the pressurization in the step S3 is intended to integrate the chips 5 on the upper surface 24a of the individual substrate 24. Because there is, even such a small pressure is enough. If pressure is applied at such a low second pressure P2, the degree to which the individual substrate is undesirably deformed can be suppressed.

  In addition, when the temperature at the time of heat-pressing in process S1 which obtains an aggregate substrate is set to 1st temperature H1, it is preferable to heat at 2nd temperature H2 lower than 1st temperature H1 in process S3 to reheat. Assuming that the first temperature H1 is 270 ° C., the second temperature H2 is a temperature obtained by adding 3 ° C. or more and 8 ° C. or less, for example, compared to the softening temperature of the thermoplastic resin. As described above, if the step S3 is performed at the second temperature H2 lower than that of the heating press in the step S1, the degree of undesired deformation of the individual substrate 24 can be suppressed.

  In the first and second embodiments, as shown in FIG. 10, step S <b> 2 is performed in a state where the aggregate substrate 22 is attached to the adhesive sheet 4. The cutting step S2 is preferably performed in a state where the collective substrate 22 is attached to the pressure-sensitive adhesive sheet 4 as described above. This is advantageous because it is possible to prevent the individual substrate 24 after being cut out from being undesirably displaced, dissipated, or dropped.

(Embodiment 3)
With reference to FIG. 15, the manufacturing method of the resin multilayer substrate in Embodiment 3 based on this invention is demonstrated. The manufacturing method of the resin multilayer substrate in the present embodiment is the same as the manufacturing method described in the first and second embodiments, but is different in the following points.

  In the present embodiment, as shown in FIG. 15, step S <b> 2 is performed with the collective substrate 22 attached to the adhesive sheet 4. In this Embodiment, process S3 to reheat is performed in the state which pulled the adhesive sheet 4 in the direction parallel to the surface of the adhesive sheet 4. FIG. That is, the individual substrate 24 is cut out while being pulled as indicated by an arrow 93 shown in FIG.

  In the present embodiment, since the pressure-sensitive adhesive sheet 4 is pulled in a direction parallel to the surface of the pressure-sensitive adhesive sheet 4 in the reheating step S3, the gap G between the individual substrates 24 is increased. Therefore, it is possible to prevent the individual substrates 24 from sticking to each other as much as possible. In particular, as described in the second embodiment, when the pressure is applied simultaneously with the heating in the reheating step S3, the thermoplastic resins of the individual substrates 24 are swelled to the sides by the pressurization in a softened state. Adjacent individual substrates 24 tend to stick together. In that respect, as described in the present embodiment, in the reheating step S3, by pulling the adhesive sheet 4, if the gap G is increased in advance, the individual substrates 24 can be prevented from sticking to each other as much as possible. it can.

  When pulling the pressure-sensitive adhesive sheet 4, it may be pulled from two opposite directions, but it is more preferable to pull from the four directions.

  In the present embodiment, for example, a number of fixing holes are provided in advance on the outer edge portion of the pressure-sensitive adhesive sheet 4, and the pressure-sensitive adhesive sheet 4 is formed by hooking these holes to some pins while the pressure-sensitive adhesive sheet 4 is pulled. The step S3 of reheating may be performed so that the pulled state can be maintained.

(Embodiment 4)
With reference to FIGS. 16-17, the manufacturing method of the resin multilayer substrate in Embodiment 4 based on this invention is demonstrated. The manufacturing method of the resin multilayer substrate in the present embodiment is similar to steps S1 to S3 as compared with the manufacturing method described in the first to third embodiments, but differs in the following points.

  FIG. 16 shows a flowchart of the method for manufacturing the resin multilayer substrate in the present embodiment. An example of the result of performing step S4 is shown in FIG. The method for manufacturing a resin multilayer substrate in the present embodiment includes a step S4 of mounting the component 3 on the individual substrate 24 after the step S3 of reheating. Here, for convenience of explanation, the arrangement of the conductor pattern 7 and the interlayer connection conductor 6 included in the individual substrate 24 is different from that shown in FIG. Thus, the conductor pattern 7 for mounting the component 3 is exposed on the upper surface of the individual substrate 24, and the component 3 is mounted using these conductor patterns 7 as external electrodes.

  In the present embodiment, the mounting of the component 3 on the individual substrate 24 is performed after the reheating step S3, so that the influence of heat in the step S3 can be prevented from reaching the component 3.

In addition, you may implement combining 1 or more of said each embodiment.
In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It is not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  2 resin layer, 3 parts, 4 adhesive sheet, 5 chips, 6 interlayer connection conductor, 7 conductor pattern, 11 via hole, 12 resin sheet with conductor foil, 13 laser beam, 15 protrusion, 17 conductor foil, 19 base material group , 20 laminate, 22 collective substrate, 24 individual substrate, 24a upper surface, 24b side surface, 31, 32 mold, 91, 92, 93 arrow.

Claims (6)

An integrated assembly board by heat-pressing in a state where pressure is applied at a temperature equal to or higher than the softening temperature of the thermoplastic resin to a laminate of a plurality of base materials mainly composed of a thermoplastic resin. Obtaining
Cutting out individual substrates from the aggregate substrate;
Look including a step of re-heating the individual substrate at the softening temperature or higher of the thermoplastic resin,
The cutting step is performed in a state where the aggregate substrate is attached to an adhesive sheet,
The process of reheating is a method for producing a resin multilayer substrate , wherein the pressure-sensitive adhesive sheet is pulled in a direction parallel to the surface of the pressure-sensitive adhesive sheet . When the time for heat pressing in the step of obtaining the aggregate substrate is the first time,
The method for producing a resin multilayer substrate according to claim 1, wherein in the reheating step, heating is performed for a second time shorter than the first time.   The method for producing a resin multilayer substrate according to claim 1 or 2, wherein the individual substrate is pressurized over at least a part of the heating time in the reheating step. When the first pressure is the pressure applied when heat pressing in the step of obtaining the aggregate substrate,
The method for producing a resin multilayer substrate according to claim 3, wherein when the individual substrate is pressurized, the pressure is increased with a second pressure lower than the first pressure. When the temperature at the time of hot pressing in the step of obtaining the aggregate substrate is the first temperature,
5. The method for producing a resin multilayer substrate according to claim 1, wherein in the reheating step, heating is performed at a second temperature lower than the first temperature. After said reheating step, the comprising the step of mounting the components on the individual substrate, the manufacturing method of the resin multilayer substrate according to any one of claims 1 to 5.

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