JP2019169592A - Module manufacturing method - Google Patents

Abstract

To provide a module manufacturing method using a shielding material so that a shield film is not formed on a terminal surface of a module element body.SOLUTION: When forming a shield film on a module body 1 having a wiring board 2, a sealing resin layer 3, and an external connection terminal 4, by providing a shielding material 5 in advance, it becomes possible to prevent adhesion of the shield film to the external connection terminal 4 by preventing the shield film from wrapping around a bottom surface of the module body 1 when forming a shield film by sputtering, so that a highly reliable module can be manufactured. In addition, when loading to a sputtering apparatus, by providing the shielding material 5, an adhesion area to a product alignment plate 6 is reduced, so that pickup after sputtering becomes easy.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a module having a shield film.

  In recent years, with the increase in the number of components in electronic devices such as smartphones and the reduction in size and height of electronic devices, noise interference between used electronic components has become a problem. For this reason, it is required to form a shield film also in the communication module product. Generally, a sputtering apparatus is used for forming the shield film. For example, as shown in FIG. 7, a component main body 101 having a plurality of bumps 102 on the bottom surface, a holder 103 composed of a laminated body of a holder main body 103b and a heat conductive sheet 103a, and an adhesive sheet 104 are attached to this. There has been proposed a film forming apparatus in which a protective film 106 is formed by being mounted on a work holding body 105 constituted by being stacked and mounted on a sputtering apparatus.

  At this time, the pressure-sensitive adhesive sheet 104 is pressed by a plurality of bumps 102 provided on the bottom surface of the component main body 101, and is locally deformed while closely contacting the bottom surface of the component main body 101 so as to enter between the bumps 102. . That is, by embedding the bumps 102 in the adhesive sheet 104, the component main body 101 is fixed to the adhesive sheet 104, and the protective film 106 is formed on the side surface and the top surface of the component main body 101 by sputtering. Further, the adhesive sheet 104 is in close contact with the bottom surface of the component main body 101, thereby preventing the film forming material from flowing around the bottom surface of the component main body 101 when being sputtered and the film forming material adhering to the bumps 102. Is also prevented.

International Publication No. 2017/038466 (see paragraphs 0024 to 0048, FIG. 6 etc.)

  However, in order to completely embed the bumps 102 in the adhesive sheet 104 and bring the adhesive sheet 104 into close contact with the bottom surface of the component main body 101, it is necessary to increase the adhesive layer of the adhesive sheet or to select a soft material for the adhesive sheet. There is. If it does so, an adhesive will adhere to the side surface of the component main body 101, and the protective film 106 may not be formed in a part of side surface of the component main body 101. FIG. In addition, a gap may be generated between the bottom surface of the component body 101 and the adhesive sheet 104 due to variations in the size of the bumps 102 and alignment when embedded in the adhesive sheet 104. There is a problem that wraparound occurs. It is very difficult to select the material of the pressure-sensitive adhesive sheet 104 and specify the process conditions so that the bump 102 is completely embedded in the pressure-sensitive adhesive sheet 104 and the adhesive does not adhere to the side surface of the component main body 101, and the design rule is sacrificed. There is a problem of becoming.

  The present invention has been made in view of the above problems, and by covering the external connection terminals of the module with a shielding material, it is possible to prevent a shield film from being formed on the back surface of the module and the external connection terminals. An object is to provide a method for manufacturing a module.

  In order to achieve the above-described object, a module manufacturing method of the present invention includes a wiring board, a component mounted on one main surface of the wiring substrate, and a resin provided on the one main surface that covers the component. A preparation step of preparing a module body including a plurality of external connection terminals provided on the other main surface of the wiring board, and a shielding material forming step of forming a shielding material on the other main surface of the wiring substrate; A plate fixing step for fixing the surface of the module body on which the shielding material is formed to a film forming plate; and a shield film for forming a shield film on the module body fixed to the film forming plate by sputtering. And a shielding material removing step for removing the shielding material, wherein the shielding material forms a shielding film at a predetermined position of the module body in the shielding film forming step. In the shielding material forming step, among the plurality of external connection terminals, at least between the external connection terminal located on the edge side of the wiring board and the edge of the wiring board. The shielding material is disposed so as to cover at least a part of the external connection terminal located on the edge side, and the height of the shielding material from the other main surface of the wiring board is the height of the external connection terminal. The shielding material is formed so as to be higher than the height from the other main surface of the wiring board.

  According to this configuration, since the external connection terminal is covered with the shielding material and then fixed to the film forming plate, it is possible to suppress the formation of the shield film on the external connection terminal. At this time, since the pressure-sensitive adhesive sheet provided on the film-forming plate can give a degree of freedom to the thickness and hardness of the pressure-sensitive adhesive, the manufacturing cost can be suppressed by selecting an inexpensive material. .

  Further, in the shielding material forming step, the shielding material may be formed so as not to reach the edge of the wiring board.

  According to this configuration, when removing the shielding material, it is possible to suppress the occurrence of burr in the shielding film.

  In the shielding material forming step, after placing the semi-cured resin on the other main surface of the wiring board, the module is pressed against a flat plate to fix the shielding material to the film formation plate. The surface may be flat.

  According to this configuration, since the adhesion surface of the module element to the adhesive sheet is flat, the module element can be easily fixed to the film forming plate.

  Moreover, in the said shielding material formation process, you may form the said shielding material by arrange | positioning solid film-like resin to the said other main surface of the said wiring board, and exposing and developing.

  According to this configuration, the shielding material can be easily formed.

  In the shielding material forming step, the shielding material may be formed so as to cover substantially the entire surface of the other main surface of the wiring board.

  According to this configuration, since the external connection terminal can be completely covered with the shielding material, it is possible to more reliably prevent the shield film from being formed on the external connection terminal.

  According to the present invention, when the shield film is formed, covering the external connection terminal with the shielding material reliably prevents the shield film from going around the bottom surface of the module body and shields the external connection terminal. A method for manufacturing a highly reliable module that can prevent the formation of a film can be provided at a low process cost.

It is sectional drawing of the intermediate process of the manufacturing method of the module concerning 1st Embodiment of this invention. FIG. 2 is a bottom view of the module element body of FIG. 1. FIG. 2 is a bottom view of the assembly of module element bodies of FIG. 1. It is sectional drawing of the modification of the process shown in FIG. FIG. 5 is a bottom view of the module element body of FIG. 4. FIG. 5 is a bottom view of the assembly of the module element bodies of FIG. 4. It is a figure which shows a part of conventional module manufacturing process.

<First Embodiment>
A method for manufacturing a module according to the first embodiment of the present invention will be described with reference to FIGS. 1 is a cross-sectional view of the module elements arranged in the film forming apparatus, FIG. 2 is a bottom view of the module elements, and FIG. 3 is a bottom view of the assembly of the module elements.

  In this embodiment, a module is manufactured by forming an assembly of a plurality of module element bodies and then separating them into individual pieces. In addition, the order of each process may be changed as needed, and a new process may be added.

  First, a component (not shown) is mounted on the upper surface 2a of the wiring board 2, a sealing resin layer 3 for sealing the component is formed, and a module element in which a plurality of external connection terminals 4 are provided on the lower surface 2b of the wiring board. A module assembly 10 of the body 1 is prepared (corresponding to a “preparation step” of the present invention).

  The wiring board 2 is formed by laminating a plurality of insulating layers formed of, for example, a low-temperature co-fired ceramic, a high-temperature co-fired ceramic, glass epoxy resin, or the like. On the upper surface 2a (corresponding to “one main surface” of the present invention) and the lower surface 2b (corresponding to “other main surface” of the present invention) of the wiring board, mounting electrodes (for mounting components or external connection terminals 4) (Not shown) is formed. Various internal wiring electrodes (not shown) and ground electrodes (not shown) are formed between adjacent insulating layers. Furthermore, a plurality of via conductors (not shown) for connecting the internal wiring electrodes are formed inside the wiring board 2. Note that each of the mounting electrode and the internal wiring electrode is formed of a metal generally adopted as a wiring electrode such as Cu, Ag, or Al. Each via conductor is formed of a metal such as Ag or Cu. Each mounting electrode may be subjected to Ni / Au plating.

  The components include semiconductor elements such as IC and PA (power amplifier), and chip components such as a chip inductor, a chip capacitor, and a chip resistor, and are mounted on the wiring board 2 by a general surface mounting technique such as solder bonding. .

  The sealing resin layer 3 is formed of a resin generally employed as a sealing resin such as an epoxy resin containing a silica filler, and seals a component. The sealing resin layer 3 has a lower surface 3b that contacts the upper surface 2a of the wiring substrate 2, an upper surface 3a that faces the lower surface 3b, and a side surface 3c. In order to increase the thermal conductivity, a filler having a high thermal conductivity such as an alumina filler may be used. The sealing resin layer 3 can be formed using a known technique such as a transfer mold method, a compression mold method, or a resin dispensing method.

  The external connection terminal 4 is used for input / output with the external substrate. For example, the external connection terminal 4 may be mounted with a metal pin on a mounting electrode and soldered, or a post electrode may be previously formed on the mounting electrode by plating.

  Next, the material of the shielding material 5 is supplied to the lower surface 2b of the wiring board 2 to form a predetermined shape (corresponding to the “shielding material forming step” of the present invention). In this embodiment, as shown in FIG. 2, the shielding material 5 is formed along the outer periphery of the lower surface 2 b of the wiring board 2 so as not to reach the edge of the module element body 1. At this time, as shown in FIG. 1, the shielding material 5 is placed so that the height of the shielding material 5 from the lower surface 2b of the wiring board 2 is higher than the height of the external connection terminal 4 from the lower surface 2b of the wiring board 2. Form. The shielding material 5 can be formed of, for example, a thermosetting resin such as a silicone resin using a known technique such as a dispensing method, an ink jet method, a printing method, or the like. Further, the shielding material 5 may be formed by a method in which an unnecessary portion is removed by an exposure / development process after a film-like material is pasted to flatten the surface. Alternatively, the shielding material 5 may be formed by applying a liquid resin and then pressing it against a flat plate to flatten the surface.

  Next, the module element assembly 10 is cut into pieces by a general dividing method such as dicing or laser processing.

  Next, a product alignment plate 6 for film formation (corresponding to the “film formation plate” of the present invention) is prepared. As the product alignment plate 6, for example, a plate in which an adhesive tape 6b is laminated on a metal plate 6a can be used. Or the plate which laminated | stacked the single-sided adhesive tape on the metal ring may be sufficient. As the adhesive tape 6b, it is desirable to select a tape that can be used in a vacuum and has heat resistance of about 120 ° C. Affixing the adhesive tape 6b to the metal plate 6a can use a general affixing method such as a roller, a press, or a tape mounter. In order to prevent the generation of bubbles, the adhesive tape 6b may be attached to the metal plate 6a in a vacuum. Moreover, in order to improve the adhesiveness of the metal plate 6a and the adhesive tape 6b, you may heat about 50 to 80 degreeC at the time of affixing.

  Next, the module body 1 is aligned with the product alignment plate 6 (corresponding to the “plate fixing step” of the present invention). The surface of the module body 1 on which the shielding material 5 is formed is attached to the adhesive tape 6 b of the product alignment plate 6, and the module body 1 is aligned on the product alignment plate 6. As the aligning machine, a generally used mounting machine can be used. Moreover, in order to improve the adhesiveness between the module element body 1 and the product alignment plate 6, overheating at about 50 ° C. to 80 ° C. may be performed after alignment.

  Next, the product alignment plate 6 to which the module body 1 is attached is set in the chamber of the sputtering apparatus.

Next, the chamber is evacuated. Considering the film quality of the shield film to be formed in the subsequent process, it is preferable that the ultimate vacuum is low. However, if the vacuum achievement is too low, the tact time becomes long and the production capacity is lowered. It is most preferable that it is * 10 < ^-3 > Pa- ¹ * 10 < ^-1 > Pa. As the sputtering apparatus, a general sputtering apparatus such as an inline type, a batch type, or a single wafer type can be used. In consideration of productivity, an apparatus provided with a load lock chamber in addition to the sputtering chamber may be used.

  Next, dry etching is performed as necessary. In dry etching, a voltage is applied to an Ar ion gun to clean the surface of the module body 1 with Ar ions. The dry etching has an effect of improving the adhesion of the shield film by cleaning the surface of the module body 1 and also causing an anchor effect by roughening the surface of the module body 1. Instead of dry etching, residual components may be removed by a dry process such as plasma cleaning or ion milling.

  Next, a shield film is formed by sputtering (corresponding to the “shield film forming step” of the present invention). The shield film is formed so as to cover the upper surface 3 a and side surface 3 c of the sealing resin layer 3 and the side surface 2 c of the wiring substrate 2, and the upper surface 3 a and side surface 3 c of the sealing resin layer 3 and the side surface 2 c of the wiring substrate 2 It is possible to form a multilayer structure having an adhesion layer laminated on the conductive layer, a conductive layer laminated on the adhesion layer, and a corrosion-resistant layer laminated on the conductive layer.

  Here, the adhesion layer is provided in order to increase the adhesion strength between the conductive layer and the sealing resin layer 3, and may be formed of, for example, a material that forms a passive state such as Ti, Cr, or SUS. it can. Further, the conductive layer is a layer that bears the substantial shielding function of the shield film, and can be formed of any metal of Cu, Ag, and Al, for example. The corrosion resistant layer is provided to prevent the conductive layer from being corroded or scratched, and can be formed of, for example, SUS. The shield film is electrically connected to the ground electrode exposed from the side surface 2c of the wiring board 2.

  After forming the shield film, the module body 1 is picked up from the adhesive tape 6b of the product alignment plate 6 and transferred to the tray. The module element body 1 is lifted while adsorbing and holding the top surface of the module element body 1 (surface on the upper surface 3a side of the sealing resin layer 3), and the back surface of the module element body 1 (surface on the lower surface 2b side of the wiring board 2). Push up to assist pick-up. Alternatively, a plurality of module bodies 1 may be picked up simultaneously using an adhesive head or the like.

  After the module body 1 is picked up, the shielding material 5 is removed (corresponding to the “shielding material removing step” of the present invention). The shielding material 5 can be removed by etching or dissolution, or can be removed using a foam release sheet.

  Finally, cleaning, printing, measurement, appearance inspection, and packaging of the product after sputtering are performed as necessary to complete the module.

  Therefore, according to the above-described embodiment, by providing the shielding material 5 on the lower surface 2b of the wiring board 2 that contacts the back surface of the module body 1, the shield film is formed on the back surface of the module body 1 at the time of sputtering. Can be prevented. That is, the shield film may be formed on the shielding material 5 provided outside the external connection terminal 4, but does not go around the back surface of the module body 1 that is inside the external connection terminal 4. For this reason, it can prevent that the reliability of a module falls by forming a shield film in the external connection terminal 4. FIG. Further, even when the sizes of the external connection terminals 4 vary, there is an effect that it is possible to prevent the shield film from being formed on the back surface of the module body 1 by providing the shielding material 5. Moreover, it is not necessary to use a special material as the adhesive sheet, and a reliable manufacturing method can be provided at a low process cost. Further, by using a liquid resin for the shielding material 5, it is possible to flatten the installation surface of the module element body 1 on the adhesive tape 6b after the shielding material 5 is formed, and the handling becomes easy. Moreover, since the contact area to the adhesive tape 6b can be reduced by providing the shielding material 5, pickup after sputtering becomes easy.

(Modification of shielding material)
The shielding member 5a may be formed so as to reach the edge of the lower surface 2b of the wiring board 2 as in the module element body 1a shown in FIGS. In this case, as shown in FIG. 6, the shielding material 5a is formed on the dicing line of the module body assembly 10a. If it carries out like this, a shield film will not be formed in the back surface (lower surface 2b of the wiring board 2) of the module base body 1a, and the reliability of a module can be improved.

  Note that the present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, you may combine the structure of above-described embodiment and a modification.

  For example, in the above-described embodiment, the shielding material 5 is formed along the outer periphery of the lower surface 2b of the wiring board 2. However, the shielding material 5 may be formed so as to cover the entire lower surface 2b of the wiring board 2.

  In addition, the present invention can be applied to various modules including parts.

DESCRIPTION OF SYMBOLS 1, 1a Module body 2 Wiring board 3 Sealing resin layer 4 External connection terminal 5, 5a Shielding material 6 Product alignment plate (film formation plate)

Claims (5)

A wiring board; a component mounted on one main surface of the wiring substrate; a sealing resin layer provided on the one main surface covering the component; and a plurality of parts provided on the other main surface of the wiring substrate. A preparation step of preparing a module body including an external connection terminal;
A shielding material forming step of forming a shielding material on the other main surface of the wiring board;
A plate fixing step of fixing the surface of the module body on which the shielding material is formed to a film forming plate;
A shield film forming step of forming a shield film by sputtering on the module element fixed to the film forming plate;
A shielding material removing step for removing the shielding material,
The shielding material shields the shield film from being formed at a predetermined position of the module element body in the shield film forming step.
In the shielding material forming step, among the plurality of external connection terminals, the external connection located on the edge side between at least the external connection terminal located on the edge side of the wiring board and the edge of the wiring board. The shielding material is arranged so as to cover at least a part of the terminal, and the height of the shielding material from the other main surface of the wiring board is from the other main surface of the wiring board of the external connection terminal. The method for manufacturing a module, wherein the shielding material is formed to be higher than a height.   The method for manufacturing a module according to claim 1, wherein in the shielding material forming step, the shielding material is formed so as not to reach the edge of the wiring board.   In the shielding material forming step, after the semi-cured resin is disposed on the other main surface of the wiring board, the module body is pressed against a flat plate, thereby fixing the shielding material to the film formation plate. 3. The module manufacturing method according to claim 1, wherein the surface is flattened.   The said shielding material is formed in the said shielding material formation process by arrange | positioning solid film-like resin to the said other main surface of the said wiring board, and exposing and developing. Module manufacturing method. 5. The module manufacturing according to claim 1, wherein, in the shielding material forming step, the shielding material is formed so as to cover substantially the entire surface of the other main surface of the wiring substrate. Method.

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