Apparatus and method for forming sealing resin used in compression molding

Abstract

To provide a compression molding apparatus and a method for forming a sealing resin, which can realize a compression molding apparatus and a compression molding method capable of preventing the occurrence of molding defects.SOLUTION: A sealing resin forming apparatus 100 according to the present invention is a forming apparatus that tablets a base resin Rm to form a sealing resin R to be used for compression molding of a workpiece W, and is equipped with a tableting mold 102 that holds a predetermined amount of base resin Rm in one or both of a pair of a lower mold 106 and an upper mold 104 that are opened and closed, and tablets the base resin R to form a sealing resin R having a predetermined shape corresponding to the shape of the workpiece W.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for forming a sealing resin used in compression molding. [Background technology]

[0002] 2. Description of the Related Art As an example of a resin sealing apparatus and a resin sealing method for sealing a workpiece having electronic components mounted on a substrate with a sealing resin and processing it into a molded product, a method using a compression molding method is known.

[0003] The compression molding method is a technology in which a predetermined amount of sealing resin is supplied to a sealing area (cavity) provided in a sealing mold comprising an upper mold and a lower mold, a workpiece is placed in the sealing area, and the upper mold and lower mold are clamped to seal the workpiece with resin. As an example, when a sealing mold having a cavity in the upper mold is used, a technology is known in which the sealing resin is supplied all at once to the center position on the workpiece and molded. On the other hand, when a sealing mold having a cavity in the lower mold is used, a technology is known in which a release film (hereinafter sometimes simply referred to as a "film") that covers the mold surface including the cavity and the sealing resin are supplied and molded (Patent Document 1: See JP 2019-145550 A). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-145550 A Summary of the Invention [Problem to be solved by the invention]

[0005] For example, when a strip-type wire-connected electronic component (semiconductor chip) is encapsulated with resin as a workpiece, the compression molding method in which a cavity is provided in the upper die has a problem that encapsulation is difficult because the wire portion of the workpiece held in the lower die comes into contact with the encapsulation resin previously supplied to the cavity or the encapsulation resin supplied onto the workpiece and deforms. Therefore, a compression molding method in which the workpiece is held in the upper die, a cavity is provided in the lower die, and encapsulation resin (granular resin, as an example) is supplied into the cavity has generally been adopted.

[0006] However, in a configuration in which a workpiece is held in the upper mold and a cavity is provided in the lower mold, when the workpiece is thin or large, there is a problem that it is difficult to hold the workpiece in the upper mold and it is likely to fall. In addition, although the sealing resin is usually supplied into the cavity of the lower mold through a film, when a thick molded product with a thickness (here, the thickness of the resin part after molding) of more than 1 mm is to be formed, the molding stroke becomes large, and there is a problem that the film is likely to be caught in the molded product, which is a molding defect. Furthermore, when a granular resin is used as the sealing resin, in addition to the problem that the film is likely to be caught in the molded product, dust is generated, and handling is difficult, there is a problem that it is difficult to supply (spray) the sealing resin evenly to the entire area in the cavity provided in the lower mold, and winding unevenness is likely to occur. In addition, there is a problem that the air contained in the gaps between the particles when the sealing resin is sprayed and the gas components due to degassing from the sealing resin when melted are not released and remain in the molded product, which is a molding defect. In particular, in the case of a workpiece in which electronic components are mounted by wire connections, there is a risk of wire flow (deformation or breakage of the wire) due to the flow of resin within the cavity during resin sealing. [Means for solving the problem]

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide a molding apparatus and a molding method for forming a sealing resin that is easy to handle, that solves the problems of a configuration in which a cavity is provided in an upper mold and that solves the problems of a configuration in which a cavity is provided in a lower mold, that prevents molding defects caused by resin flow, uneven winding, residual gas, and dust generation during molding, and that enables the formation of molded products with large thickness dimensions.

[0008] The present invention solves the above problems by the solution means described below as one embodiment.

[0009] The molding device according to one embodiment is a molding device for forming a molding resin to be used for compression molding of a workpiece by tableting a base resin, and is required to include a tableting die that accommodates a predetermined amount of the base resin in one or both of a pair of a lower die and an upper die that are opened and closed, and tablets the base resin to form the molding resin having a predetermined shape corresponding to the shape of the workpiece. For example, a workpiece having a configuration in which electronic components are mounted on a substrate is used as the workpiece.

[0010] It is also preferable to provide a lower mold film supply unit that supplies a release film to be adsorbed to the mold surface of the lower mold, and an upper mold film supply unit that supplies a release film to be adsorbed to the mold surface of the upper mold.

[0011] Furthermore, for the workpiece, it is preferable that the specified shape is a shape that does not abut the electronic components when the sealing resin is placed on the substrate, and the specified amount is an amount that is set by measuring the number of electronic components mounted on one of the substrates for each workpiece and calculating the amount of resin required, or an amount that is set by selecting from multiple types of standard amounts corresponding to the type of the workpiece.

[0012] It is preferable that a powder resin is used as the base resin.

[0013] Moreover, a method for forming a sealing resin according to one embodiment is a method for forming a sealing resin by tableting a base resin to form a sealing resin to be used for compression molding of a workpiece, and is required to include a tableting step in which a predetermined amount of the base resin is placed in a tableting die and tableted to form the sealing resin having a predetermined shape corresponding to the shape of the workpiece. Effect of the Invention

[0014] By using the sealing resin formed by the molding apparatus and method according to the present invention, it is possible to realize a compression molding apparatus and a compression molding method that can solve the problems of a configuration in which a cavity is provided in an upper mold and a configuration in which a cavity is provided in a lower mold, prevent molding defects caused by resin flow, uneven winding, residual gas, and dust generation during molding, and form molded products with large thickness dimensions. Also, handling is easier than granular resin, especially when supplying and setting. [Brief description of the drawings]

[0015] [Figure 1] 1 is a plan view showing an example of a compression molding apparatus in which a sealing resin formed by a forming apparatus and a forming method according to an embodiment of the present invention is used. [Diagram 2] 1A to 1C are explanatory diagrams illustrating an example of a compression molding method in which a sealing resin formed by the forming apparatus and forming method according to an embodiment of the present invention is used. [Diagram 3] FIG. 3 is an explanatory diagram following FIG. 2. [Figure 4] FIG. 4 is an explanatory diagram following FIG. [Diagram 5] 11A to 11C are explanatory diagrams illustrating another example of a compression molding method in which a sealing resin formed by the forming apparatus and forming method according to an embodiment of the present invention is used. [Figure 6] FIG. 6 is an explanatory diagram following FIG. [Figure 7] FIG. 7 is an explanatory diagram following FIG. [Figure 8] 1 is a side view illustrating an example of an apparatus for forming a sealing resin according to an embodiment of the present invention. [Figure 9]FIG. 9 is a front cross-sectional view showing an example of a tableting die of the forming apparatus shown in FIG. [Figure 10] 5A to 5C are explanatory diagrams of a method for forming a sealing resin according to an embodiment of the present invention. [Figure 11] FIG. 11 is an explanatory diagram following FIG. [Figure 12] FIG. 12 is an explanatory diagram following FIG. [Figure 13] 1 is a perspective view showing an example of a sealing resin formed by a forming apparatus and a forming method according to an embodiment of the present invention; [Figure 14] 11 is a perspective view showing another example of a sealing resin formed by the forming apparatus and forming method according to the embodiment of the present invention. FIG. [Figure 15] 11 is a perspective view showing another example of a sealing resin formed by the forming apparatus and forming method according to the embodiment of the present invention. FIG. [Figure 16] 11 is a perspective view showing another example of a sealing resin formed by the forming apparatus and forming method according to the embodiment of the present invention. FIG. [Figure 17] Fig. 17A is an enlarged view of part A in Fig. 2. Fig. 17B is an explanatory view following Fig. 17A. [Figure 18] FIG. 1 is an explanatory diagram of a conventional compression molding method. [Figure 19] FIG. 1 is an explanatory diagram of a conventional compression molding method. [Figure 20] FIG. 2 is a front cross-sectional view showing another example of a tableting die of a forming apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] (Compression molding device and compression molding method) The sealing resin forming apparatus and method according to the embodiment of the present invention are an apparatus and method for forming sealing resin R used in compression molding of a workpiece W. First, an overview of a compression molding apparatus 1 and a compression molding method for resin sealing (compression molding) a workpiece W using the sealing resin R will be described. Here, FIG. 1 is a plan view (schematic view) showing an example of the compression molding apparatus 1.

[0017] The workpiece W to be sealed has a configuration in which electronic components Wb are mounted on a substrate Wa. More specifically, examples of the substrate Wa include plate-shaped members such as a resin substrate, a ceramic substrate, a metal substrate, a carrier plate, a lead frame, and a wafer. Examples of the electronic components Wb include a semiconductor chip, a MEMS chip, a passive element, a heat sink, a conductive member, and a spacer. The shape of the substrate Wa is a rectangular shape (striped shape), a square shape, a circular shape, and the like. The number of electronic components Wb mounted on one substrate Wa is set to one or more (for example, in a matrix shape, etc.).

[0018] Examples of methods for mounting the electronic components Wb on the substrate Wa include wire bonding mounting, flip chip mounting, etc. Alternatively, in the case of a configuration in which the substrate (glass or metal carrier plate) Wa is peeled off from the molded product Wp after resin sealing, there is also a method in which the electronic components Wb are attached using a thermally peelable adhesive tape or an ultraviolet-curable resin that is cured by exposure to ultraviolet light.

[0019] As examples of the film F, a film material having excellent heat resistance, peelability, flexibility, and extensibility, such as PTFE (polytetrafluoroethylene), ETFE (polytetrafluoroethylene polymer), PET, FEP, fluorine-impregnated glass cloth, polypropylene, polyvinylidine chloride, etc. are preferably used. The film F is also used when forming the sealing resin R in the forming device 100 described later.

[0020] As shown in Fig. 1, the compression molding apparatus 1 mainly comprises a supply unit 10A for supplying the workpiece W, a press unit 10B for sealing the workpiece W with resin and processing it into a molded product Wp, and a storage unit 10C for storing the molded product Wp. As an example, the supply unit 10A, the press unit 10B, and the storage unit 10C are arranged in this order along the X direction in Fig. 1. However, the above configuration is not limited to this, and the equipment configuration within the unit, the number of units (particularly the number of press units), the arrangement order of the units, and the like can be changed. Also, a configuration including units other than those described above (all not shown) is possible.

[0021] In addition, in the compression molding apparatus 1, a guide rail 20 is provided linearly across each unit, and a transport device (first loader) 22 for transporting the workpiece W and the sealing resin R, and a transport device (second loader) 24 for transporting the molded product Wp (which may be used to transport the sealing resin R) are provided so as to be movable between predetermined units along the guide rail 20. However, the configuration is not limited to the above, and a configuration may be provided with a common (single) transport device (loader) for transporting the workpiece W, the sealing resin R, and the molded product Wp (not shown). Also, the transport device may be configured to include a robot hand or the like instead of a loader.

[0022] In addition, in the compression molding apparatus 1, a control unit 30 that controls the operation of each mechanism in each unit is disposed in the supply unit 10A (it may be disposed in another unit).

[0023] The press unit 10B includes a pair of sealing dies that are opened and closed by a press device 250. As an example, the sealing dies may be configured such that a cavity is provided in an upper die (sealing die 202), or as another example, may be configured such that a cavity is provided in a lower die (sealing die 302). The press device 250 is also provided with a film supply unit 211 that supplies a film F for covering a die surface 204a (predetermined area) including the inner surface of the cavity 208 in the upper die 204. As an example, the film F is in a roll shape, but may also be in a rectangular shape.

[0024] As an example, steps of a compression molding method performed using a compression molding apparatus 1 equipped with a sealing mold 202 will be described with reference to FIGS.

[0025] First, a preparation step (sealing preparation step) is performed. Specifically, a step of adjusting and heating the upper mold 204 and the lower mold 206 to a predetermined temperature (for example, 100°C to 300°C) is performed. Also, a step of operating the film supply unit 211 to supply new film F and adsorb it to cover a predetermined area of ​​the mold surface 204a including the inner surface of the cavity 208 in the upper mold 204 is performed.

[0026] After the preparation step, a workpiece holding step is performed in which the workpiece W is held by the workpiece holding portion 205 of the lower die 206. Specifically, the workpiece W supplied from the supply magazine 12 is held by the first loader 22 and carried into the sealing die 202, and is held by the workpiece holding portion 205 of the lower plate 242 (die surface 206a).

[0027] After the workpiece holding step, a resin placing step is performed in which the sealing resin R is placed on the workpiece W held by the workpiece holding part 205 (see FIG. 2). Specifically, the sealing resin R formed in a sealing resin forming device (which may simply be referred to as a "forming device") 100 described below is held by a first loader 22 (or another conveying device) and carried into the sealing die 202, and placed on the workpiece W held by the workpiece holding part 205.

[0028] Alternatively, as another example of the resin placing step, the sealing resin R formed in the forming apparatus 100 may be placed on the workpiece W before the above-described workpiece holding step. In this case, the workpiece holding step is a step of holding the workpiece W with the sealing resin R placed thereon in the workpiece holding section 205. That is, the first loader 22 holds the workpiece W with the sealing resin R placed thereon, carries it into the sealing die 202, and holds it in the workpiece holding section 205. This has the advantage of performing the workpiece W and the sealing resin R in the sealing die 202 at once, rather than separately.

[0029] Next, a resin sealing step is performed in which the workpiece W is sealed with sealing resin R and processed into a molded product Wp. Specifically, the sealing mold 202 is closed, and the cavity piece 226 is relatively lowered in the cavity 208 surrounded by the clamper 228 to perform the mold closing step in which the sealing resin R is heated and pressurized against the workpiece W. This thermally hardens the sealing resin R, completing the resin sealing (compression molding) (see FIG. 3).

[0030] The steps following the above mold closing step are the same as those in the conventional compression molding method. In summary, a mold opening step is performed in which the sealing mold 202 is opened and the molded product Wp and the used film F are separated so that the molded product Wp can be removed (see FIG. 4). Next, a molded product carrying-out step is performed in which the second loader 24 carries the molded product Wp out of the sealing mold 202 and transports it to the storage unit 10C. As an example, the transported molded product Wp is stored in the storage magazine 14. In addition, after or in parallel with the molded product carrying-out step, a step is performed in which the film supply unit 211 is operated to send out the used film F from the sealing mold 202 and send a new film F into the sealing mold 202 and set it therein.

[0031] The above are the main steps of the compression molding method performed using the compression molding apparatus 1 when the sealing mold 202 is provided. However, the above order of steps is only an example, and the order of steps can be changed or steps can be performed in parallel as long as there is no problem.

[0032] As another example, steps of a compression molding method performed using a compression molding apparatus 1 equipped with a sealing mold 302 will be described with reference to Figs. 5 to 7. In this case, the press device 250 is provided with a film supply unit 311 that supplies a film F for covering a mold surface 306a (predetermined area) including the inner surface of a cavity 308 in a lower mold 306. Note that, as one example, the film F is in a roll shape, but it may also be in a rectangular shape.

[0033] First, a preparation step (sealing preparation step) is performed. Specifically, a step of adjusting and heating upper mold 304 and lower mold 306 to a predetermined temperature (for example, 100°C to 300°C) is performed. Also, a step of operating film supply unit 311 to supply new film F and adsorb it to cover a predetermined area of ​​mold surface 306a including the inner surface of cavity 308 in lower mold 306 is performed.

[0034] After the preparation step, a workpiece holding step is performed in which the workpiece W is held by the workpiece holding portion 305 of the upper die 304. Specifically, the workpiece W supplied from the supply magazine 12 is held by the first loader 22 and carried into the sealing die 302, and is held by the workpiece holding portion 305 of the upper plate 342 (die surface 304a).

[0035] After the workpiece holding step, a resin holding step is performed (it may be performed before the workpiece holding step or in parallel). The resin holding step includes the following steps: The sealing resin R is held in the cavity 308 of the lower die 306 (see FIG. 5). Specifically, the sealing resin R formed in the forming device 100 is held by the first loader 22 (or another conveying device) and carried into the sealing die 302, and is housed in the cavity 308 (specifically, it is placed on the upper surface of the cavity piece 326).

[0036] Next, a resin sealing process is performed in which the workpiece W is sealed with sealing resin R and processed into a molded product Wp. Specifically, the sealing mold 302 is closed, and the cavity piece 326 is relatively raised in the cavity 308 surrounded by the clamper 328 to perform the mold closing process in which the sealing resin R is heated and pressurized against the workpiece W. This thermally hardens the sealing resin R, completing the resin sealing (compression molding) (see FIG. 6).

[0037] The steps following the above mold closing step are the same as those in the conventional compression molding method. In summary, a mold opening step is performed in which the sealing mold 302 is opened and the molded product Wp and the used film F are separated so that the molded product Wp can be taken out (see FIG. 7). Next, a molded product carrying-out step is performed in which the second loader 24 carries the molded product Wp out of the sealing mold 302 and transports it to the storage unit 10C. As an example, the transported molded product Wp is stored in the storage magazine 14. In addition, after or in parallel with the molded product carrying-out step, a step is performed in which the film supply unit 311 is operated to send out the used film F from the sealing mold 302 and send a new film F into the sealing mold 302 and set it therein.

[0038] The above are the main steps of the compression molding method performed using the compression molding apparatus 1 when the sealing mold 302 is provided. However, the above order of steps is only an example, and the order of steps can be changed or steps can be performed in parallel as long as no problems occur.

[0039] (Sealing resin forming device) Next, the forming apparatus 100 for forming the sealing resin R used in the compression molding apparatus 1 and the compression molding method will be described with reference to Figs. 8 and 9. The forming apparatus 100 processes the base resin Rm to form the sealing resin R. Here, Fig. 8 is a side view (schematic view) showing an example of the forming apparatus 100. The forming apparatus 100 may be provided either inside or outside the compression molding apparatus 1.

[0040] In this embodiment, a thermosetting resin (for example, an epoxy resin containing a filler, but not limited thereto) is used as the base resin Rm and the sealing resin R formed from the base resin Rm. The sealing resin R is formed as a solid or semi-solid resin having a predetermined shape (details will be described later) that corresponds to the shape of the workpiece W. Usually, one piece constitutes the "whole" of the required amount of sealing (one time per workpiece W), but it may be configured so that several pieces (for example, about two or three pieces) are divided to constitute the "whole" of the required amount of sealing. In addition, the above-mentioned "semi-solid" does not mean a completely solid state, but a state in which it is melted to the so-called B stage. In addition, a powder resin (form) that is a thermosetting resin (property) is preferably used for the base resin Rm (details will be described later). However, it is not limited thereto, and a granular resin, a crushed resin, a solid resin, a liquid resin, or a resin that is a combination of a plurality of them may be used.

[0041] As shown in Fig. 8, the forming apparatus 100 is equipped with a tableting die 102 having a pair of dies that are opened and closed (for example, a combination of a plurality of die blocks, die plates, die pillars, and other members made of alloy tool steel). Also, the forming apparatus 100 is equipped with a press device 150 that drives the tableting die 102 to open and close. Here, Fig. 9 is a front cross-sectional view (schematic view) showing an example of the tableting die 102.

[0042] As shown in FIG. 8, the press machine 150 includes a pair of platens 154, 156, a plurality of tie bars 152 on which the pair of platens 154, 156 are supported, and a drive device for moving (raising and lowering) the platen 156. Specifically, the drive device includes a drive source (e.g., an electric motor) 160 and a drive transmission mechanism (e.g., a ball screw or a toggle link mechanism) 162 (however, the present invention is not limited to this). In this embodiment, the platen 154 on the upper side in the vertical direction is set as a fixed platen (a platen fixed to the tie bars 152), and the platen 156 on the lower side is set as a movable platen (a platen slidably held by the tie bars 152 and raised and lowered). However, the present invention is not limited to this, and the platens may be set upside down, i.e., the upper side may be set as a movable platen and the lower side as a fixed platen, or both the upper side and the lower side may be set as movable platens (neither is shown).

[0043] On the other hand, as shown in Fig. 9, the tableting die 102 includes an upper die 104 on the upper side in the vertical direction and a lower die 106 on the lower side as a pair of dies disposed between the pair of platens 154, 156 in the press device 150. The upper die 104 is assembled to the upper platen (in this embodiment, the fixed platen 154), and the lower die 106 is assembled to the lower platen (in this embodiment, the movable platen 156). The upper die 104 and the lower die 106 approach and move away from each other to close and open the die (the vertical direction (up and down direction) is the die opening and closing direction). In the tableting die 102 according to this embodiment, the upper die 104 constitutes a so-called "punch die", and the lower die 106 constitutes a so-called "mortar die".

[0044] Next, the lower die 106 of the tableting die 102 will be described in detail. As shown in Fig. 9, the lower die 106 is equipped with a lower die chase 110, a cavity piece 126 held thereby, a clamper 128, etc. The lower die chase 110 is fixed to the upper surface of a support plate 114 via a support pillar 112. A cavity 108 is provided on the upper surface of the lower die 106 (the surface on the upper die 104 side). A predetermined amount of base resin Rm is accommodated in this cavity 108.

[0045] The clamper 128 is configured in an annular shape so as to surround the cavity piece 126, and is assembled to be movable up and down while being spaced apart (floating) from the upper surface of the support plate 114 via the pushing pin 122 and the clamper spring 124 (a biasing member exemplified by a coil spring, for example) (however, the assembly structure is not limited to this). The cavity piece 126 constitutes the inner part (bottom part) of the cavity 108, and the clamper 128 constitutes the side part of the cavity 108. The shape and number of cavities 108 provided in one lower mold 106 are set appropriately (one or multiple).

[0046] Here, the press device 150 is provided with a lower die film supplying section 111 that supplies a film F for covering the die surface 106a (predetermined area) including the inner surface of the cavity 108 in the lower die 106. Note that, as an example, the film F is in a roll shape, but it may also be in a rectangular shape.

[0047] Furthermore, the lower mold 106 is provided with suction paths (holes, grooves, etc.) (not shown) communicating with a suction device on the upper surface of the clamper 128, on the boundary between the clamper 128 and the cavity piece 126, etc. This allows the film F supplied from the lower mold film supply unit 111 to be adsorbed and held on the mold surface 106a including the inner surface of the cavity 108.

[0048] In this embodiment, a lower die heating mechanism (not shown) is provided to heat the lower die 106 to a predetermined temperature. This lower die heating mechanism includes a heater (e.g., an electric wire heater), a temperature sensor, a power source, etc., and heating is controlled by the control unit 30. As an example, the heater is built into the lower die chase 110 and is configured to apply heat to the entire lower die 106 and the base resin Rm contained in the cavity 108. At this time, the lower die 106 is heated to a predetermined temperature (e.g., 50°C to 80°C) at which the base resin Rm does not thermally cure (mainly cure).

[0049] Next, the upper die 104 of the tableting die 102 will be described in detail. As shown in Fig. 9, the upper die 104 is equipped with a tableting plate 142 that presses a predetermined amount of base resin Rm contained in a cavity 108 of the lower die 106 to form (compress) the sealing resin R having a predetermined shape corresponding to the shape of the workpiece W (the details of the forming method will be described later). The tableting plate 142 is held (fixed) by an upper die chase 140. As an example, a leg forming groove (including a recess) 143 for forming the leg Rb of the sealing resin R is provided on the lower surface (surface on the lower die 106 side) of the tableting plate 142.

[0050] Here, the press device 150 is provided with an upper die film supplying section 113 that supplies a film F for covering the die surface 104a (predetermined area) of the upper die 104. Note that, as an example, the film F is in a roll shape, but it may also be in a rectangular shape.

[0051] Furthermore, the upper die 104 is provided with suction paths (holes, grooves, etc.) (not shown) communicating with a suction device on the tableting plate 142, etc. This allows the film F supplied from the upper die film supply unit 113 to be adsorbed and held on the die surface 104a.

[0052] In this embodiment, an upper die heating mechanism (not shown) is provided for heating the upper die 104 to a predetermined temperature. This upper die heating mechanism includes a heater (e.g., an electric wire heater), a temperature sensor, a power source, etc., and heating is controlled by the control unit 30. As an example, the heater is built into the upper die chase 140 and is configured to apply heat to the entire upper die 104. At this time, the upper die 104 is heated to a predetermined temperature (e.g., 50°C to 80°C) at which the base resin Rm held (contained) in the lower die 106 is not thermally cured (mainly cured).

[0053] (Method of forming sealing resin) Next, there will be described steps of the sealing resin forming method according to the present embodiment, which is carried out using the above-mentioned forming apparatus 100. Here, Fig. 10 to Fig. 12 are explanatory views of each step, and are illustrated as front cross-sectional views taken in the same direction as Fig. 9.

[0054] First, a preparation step (tabletting preparation step) is performed. The preparation step includes the following steps. A lower mold heating step is performed in which the lower mold 106 is adjusted to a predetermined temperature (a temperature at which the base resin Rm and the sealing resin R do not fully cure, for example, 50°C to 80°C) and heated by the lower mold heating mechanism. In addition, an upper mold heating step is performed in which the upper mold 104 is adjusted to a predetermined temperature (a temperature at which the base resin Rm and the sealing resin R do not fully cure, for example, 50°C to 80°C) and heated by the upper mold heating mechanism. In addition, a lower mold film supplying step is performed in which the lower mold film supplying unit 111 is operated to supply a new film F and adsorb it so as to cover a predetermined area of ​​the mold surface 106a including the inner surface of the cavity 108 in the lower mold 106. In addition, an upper mold film supplying step is performed in which the upper mold film supplying unit 113 is operated to supply a new film F and adsorb it so as to cover a predetermined area of ​​the mold surface 104a of the upper mold 104.

[0055] After the preparation step, a tableting step is carried out in which the base resin Rm is tableted to form a solid or semi-solid resin having a predetermined shape (described later) corresponding to the overall shape of the workpiece W as the encapsulating resin R. Specifically, a predetermined amount of the base resin Rm is accommodated in the cavity 108 of the lower die 106 by a dispenser or the like (not shown) (see FIG. 10). Next, the press device 150 is operated to close the tableting die 102 heated to the above-mentioned predetermined temperature (see FIG. 11). At this time, the cavity piece 126 rises relatively in the cavity 108, and the base resin Rm is tableted (sandwiched and pressed) between the cavity piece 126 and the tableting plate 142. As a result, a solid or semi-solid encapsulating resin R having a predetermined shape and not yet thermally cured (mainly cured) is formed. At this time, the base resin Rm entering the leg forming groove 143 of the tableting plate 142 through the film F becomes the leg Rb of the sealing resin R, and the other (remaining) base resin Rm becomes the main body Ra of the sealing resin R (the detailed configuration of the sealing resin R will be described later). As a modified example of the tableting process, a portion of a predetermined amount of base resin Rm may be held (welded, gripped, etc.) by the upper die 104 (not shown). Also, although the leg forming groove 143 is provided in the tableting plate 142, it may be provided in the cavity piece 126 or in both.

[0056] It is important that the above tableting step is carried out at a temperature at which the base resin Rm does not undergo thermal curing (full curing) (the lower die 106 and the upper die 104 are heated to a temperature at which the base resin Rm does not undergo thermal curing (full curing)) so that the encapsulating resin R formed can be thermally cured (full cured) in the subsequent resin encapsulating step (a step of the compression molding method). As described above, the "temperature at which the base resin Rm does not undergo thermal curing (full curing)" varies depending on the material of the base resin Rm, but is specifically about 50°C to 80°C (about 70°C in this embodiment).

[0057] Here, the "predetermined shape" of the sealing resin R will be described. As an example, in the case of the sealing resin R used in the compression molding apparatus 1 when the sealing mold 202 is provided, the "predetermined shape" is a shape that does not come into contact with the electronic component Wb (including the wire in the case of the electronic component Wb having a wire) when placed on the base material Wa of the work W. As an example, as shown in FIG. 2, the sealing resin R is preferably provided with a plate-shaped or block-shaped main body Ra and legs Rb that are intermittently (or continuously) erected on one surface of the main body Ra (the surface facing the electronic component Wb of the work W) (however, the shape is not limited to this). The main body Ra is a size that fits into the cavity 208 in a plan view, and considering the resin flow, a size that is slightly smaller than the shape of the cavity 208 (particularly the cavity piece 226) is preferable. In addition, the legs Rb need to have a height H (see FIG. 17A) that does not come into contact with the electronic component Wb, but this does not exclude contact to the extent that the wire does not undergo plastic deformation. The legs Rb are arranged at a position where they do not contact the electronic components Wb in a plan view of the main body Ra, and where the main body Ra will not tilt when placed on the base material Wa of the work W. Furthermore, it is preferable that the legs Rb are arranged between the electronic components Wb or at the outer periphery of the electronic components Wb so as not to damage the wiring (particularly the wires) of the work W even a little during molding. The total amount of resin in the plate-shaped or block-shaped main body Ra and the legs Rb may be just the right amount or may be a large amount of resin as long as it is sufficient for one compression molding. Details of specific configuration examples of the sealing resin R (FIGS. 13 to 16) will be described later.

[0058] As another example, in the case of the sealing resin R used in the compression molding apparatus 1 when the sealing die 302 is provided, the "predetermined shape" is a shape in which, when the upper die 304 is gradually approached to the lower die 306 during the closing of the sealing die 302, the tip (upper end) of the leg Rb of the sealing resin R accommodated in the cavity 308 comes into contact with the base material Wa of the work W held by the work holding part 305, and the main body Ra of the sealing resin R does not come into contact with the electronic component Wb of the work W (the electronic component Wb having a wire includes the wire). Note that the specific shape of the sealing resin R is similar to that of the sealing resin R used in the compression molding apparatus 1 when the sealing die 202 is provided (see FIG. 17A, and FIGS. 13 to 16), and therefore repeated description will be omitted. However, the sealing resin R is not limited to the configuration shown in FIG. 17A, and FIGS. 13 to 16, and may have a configuration in which the upper surface is formed flat without providing the leg Rb on the upper surface (not shown).

[0059] Next, a resin amount setting step for setting the "predetermined amount" of the base resin Rm will be described. As an example of the resin amount setting step, for each workpiece W to be sealed, the number of electronic components Wb mounted on one substrate Wa (the number of mounted or missing components, and may also include measuring the height of the electronic components Wb) is measured by a measuring mechanism or the like (not shown), and the total volume of the electronic components Wb is subtracted from the volume of the cavities 208, 308 of the sealing molds 202, 302 to calculate the amount of resin (in grams) required for resin sealing (compression molding), and set the "predetermined amount". Alternatively, as another example of the resin amount setting step, multiple types of fixed amounts corresponding to the types of workpieces W to be sealed are prepared, and the control unit 30 or an operator selects one of the fixed amounts that is optimal according to the type of workpiece W to set the "predetermined amount". In the case of the fixed amount, it is important that the amount of resin is not insufficient during resin sealing (compression molding). Either setting allows an appropriate amount of base resin Rm to be supplied to the workpiece W. Therefore, in particular, it is possible to prevent molding defects caused by a shortage of the amount of resin required during resin sealing, and further, it is possible to prevent waste caused by supplying an excessive amount of resin.

[0060] In addition, it is preferable to use a powder resin as the base resin Rm. This allows the "predetermined amount" of resin to be adjusted and supplied with extremely high accuracy compared to the case where a granular resin or a crushed resin is used. However, the base resin Rm is not limited to a powder resin.

[0061] After the tableting step, a mold opening step is performed in which the tableting mold 102 is opened and the sealing resin R and the used film F are separated to enable removal of the sealing resin R (see FIG. 12). In this embodiment, by providing the lower mold film supplying step and upper mold film supplying step described above, the film F is disposed on both the mold surface 106a of the lower mold 106 and the mold surface 104a of the upper mold 104, so that the sealing resin R formed by tableting can be easily released and damage due to adhesion of the resin to the mold can be prevented.

[0062] After or in parallel with the mold opening process, the lower mold film supply unit 111 and the upper mold film supply unit 113 are operated to send out the used film F from within the tableting mold 102 and to send and set a new film F into the tableting mold 102, thereby carrying out a film supply process (lower mold film supply process, upper mold film supply process).

[0063] (Sealing resin) Next, specific configuration examples of the sealing resin R formed by the above-mentioned forming apparatus and forming method are shown in Figs. 13 to 16, and the features of each will be described.

[0064] First, as a configuration common to each example shown in FIGS. 13 to 16, the main body portion Ra is formed in a plate shape (note that it may also be in a shape other than a plate shape, for example, a block shape having concave portions, convex portions, etc.). Further, the leg portion Rb is erected on the main body portion Ra such that when the encapsulating resin R is placed at a predetermined position (set position in design) on the base material Wa of the work W, it does not contact the electronic component Wb of the work W, and is formed to a height H (see FIG. 17A) that can ensure a distance at which the main body portion Ra does not contact the electronic component Wb. As described above, in the tableting process, the base resin Rm that enters the leg forming groove 143 of the tableting plate 142 via the film F becomes the leg portion Rb of the encapsulating resin R, and the other (remaining) base resin Rm becomes the main body portion Ra of the encapsulating resin R.

[0065] In the example of the encapsulating resin R shown in FIG. 13, the leg portion Rb is formed as a convex body Rb1 in which all (or part may also be) are arranged in a dot shape. As an example of the convex body Rb1, it is arranged at a plurality of positions and is formed in a shape such that the ratio t of the length L1 to the width W1 in a plan view is, for example, 0.5 ≦ t ≦ 2. According to this, by the configuration in which the leg portion Rb is a columnar shape arranged in a dot shape, the encapsulating resin R placed on the work W can be suppressed from flowing during compression molding. Therefore, wire flow and the like can be prevented, and the molding quality can be improved.

[0066] In the example of the encapsulating resin R shown in FIG. 14, the leg portion Rb is formed as a convex body Rb2 in which part (or all may also be) are arranged in a linear shape. As an example of the convex body Rb2, it is arranged at one position (or may be at a plurality of positions) and is formed in a shape such that the ratio t of the length L2 to the width W2 in a plan view is, for example, t < 0.5 or 2 < t. According to this, resin flow can be intentionally generated from the leg portion Rb (in this case, the convex body Rb2) having a dike-like configuration of a predetermined length, and filling of the encapsulating resin R into a narrow portion (for example, between the base material Wa to which a flip chip is connected and the electronic component Wb) in the work W can be promoted. Therefore, it is possible to prevent gas from remaining in the molded product Wp, and the molding quality can be improved.

[0067] In the example of the sealing resin R shown in FIG. 15, the leg portion Rb is formed as a convex body Rb3 that is arranged so as to surround the entire periphery (referring to the outer edge region) of the main body portion Ra intermittently (or may be continuously). As an example of the convex body Rb3, convex bodies having the same configuration as the above Rb2 are formed in a continuous manner so as to form a periphery with gaps L3 at predetermined intervals. Generally, the outer peripheral position of the sealing resin R in the molded product Wp is a position that is cut by a dicer or the like when it is divided into individual pieces, and since there is no electronic component Wb, a larger amount of resin is required for sealing compared to the central position. Therefore, by providing the leg portion Rb (in this case, the convex body Rb3) that is arranged so as to surround the entire periphery as in this configuration, it is possible to supply a large amount of resin to the outer peripheral position while suppressing the resin flow during compression molding. Furthermore, by providing the gap L3, the discharge of gas components such as air from the inside (center) to the outside is promoted.

[0068] On the other hand, the example of the sealing resin R shown in FIG. 16 is a configuration example regarding the other surface of the main body part Ra (the surface on the side on which the leg part Rb is not provided, i.e., the surface on the side that does not face the electronic component Wb of the workpiece W). Specifically, the main body part Ra has linear grooves Rg formed on the other surface at the position where dicing for individualization is performed. This can reduce wear of the dicing blade and reduce dust generated during dicing. As an example, the grooves Rg are provided in a lattice shape in accordance with the dicing position, but are not limited to this. In order to form the grooves Rg, a tableting process may be performed using a cavity piece 126 having a correspondingly shaped protrusion (not shown) on its upper surface.

[0069] As described above, by using the sealing resin R formed by the forming apparatus and forming method according to the present invention, a compression molding apparatus and a compression molding method that have the following effects can be realized. Specifically, the compression molding apparatus and the compression molding method can prevent molding defects caused by resin flow, uneven winding, residual gas, and dust generation during molding. In addition, it is possible to form not only thin molded products Wp (thickness dimension less than 1 mm) but also thick molded products Wp (thickness dimension 1 mm or more). Although the upper limit of the thickness dimension depends on various setting conditions, it is considered that it is possible to form a product up to about 10 mm. In addition, handling during supply and setting is made easier.

[0070] Furthermore, the compression molding apparatus and compression molding method can solve the problem that occurs when a cavity is provided in the upper mold. That is, in a conventional compression molding apparatus in which a cavity is provided in the upper mold, when performing a mold closing process on a workpiece W on which a strip-type wire-connected electronic component (semiconductor chip) Wb is mounted, the wire portion of the workpiece held by the lower mold comes into contact with the sealing resin previously supplied to the cavity or the sealing resin previously supplied onto the workpiece, and is deformed or cut, making resin sealing difficult. This problem can be solved by adopting a configuration that uses the sealing resin R formed by the apparatus and method according to the present embodiment, that is, a solid or semi-solid resin formed into a predetermined shape corresponding to the shape of the workpiece W.

[0071] Specifically, during the mold closing process, the sealing resin R is heated and softened and melted, as shown in the transition from FIG. 17A to FIG. 17B (note that FIG. 17A and FIG. 17B are enlarged views of part A in FIG. 2). At this time, the resin (specifically, the main body part Ra) comes into uniform contact with all the wires (see FIG. 17B). This makes it possible to prevent the wires from being deformed or cut.

[0072] In addition, when the inventors of the present application actually conducted experiments in the above-mentioned compression molding apparatus 1 using sealing resin R formed by the apparatus and method of this embodiment, it was confirmed that deformation and breakage of the wire was prevented and molding quality was improved compared to a conventional compression molding apparatus having a configuration in which a workpiece W is held in the upper die, a cavity is provided in the lower die, and sealing resin (specifically, granular resin) is supplied to the cavity.

[0073] On the other hand, the compression molding apparatus and compression molding method can also solve the problem that occurs when a cavity is provided in the lower mold. That is, in a conventional compression molding apparatus in which a cavity is provided in the lower mold, the particle size and height (lamination thickness) of the sealing resin (granular resin) contained in the cavity are not uniform, especially when granular resin is used as the sealing resin. Therefore, for example, depending on the type and melting state of the granular resin, it may not be completely liquid (low viscosity state), and when a mold closing process is performed on a workpiece W on which a strip-type wire-connected electronic component (semiconductor chip) Wb is mounted, as shown in FIG. 18, depending on the position, there is a problem that the wire portion of the workpiece held by the upper mold comes into strong (large) contact with the sealing resin (granular resin) and is deformed or cut. Furthermore, as shown in FIG. 19, there is a problem that a large resin flow occurs in the cavity, and the wire portion is deformed or cut. This problem can be solved by adopting a configuration that uses the sealing resin R formed by the apparatus and method according to this embodiment, that is, a solid or semi-solid resin formed into a predetermined shape corresponding to the shape of the workpiece W.

[0074] Specifically, the reason is the same as that explained in FIG. 17A and FIG. 17B above, and during the mold closing process, the softening and melting of the sealing resin R due to heating proceeds, and the resin (specifically, the main body part Ra) comes into contact with all the wires uniformly. From that viewpoint, the sealing resin R is not limited to the configuration shown in FIG. 13 to FIG. 16, and may have a configuration (not shown) in which the upper surface is formed in a flat shape without providing the leg part Rb on the upper surface, and this configuration also makes it possible to solve the problem caused by the non-uniformity of the particle size and height (lamination thickness) compared to the conventional technology using granular resin. In addition, by making the forming device 100 of the sealing resin R and the compression molding device 1 separate devices, the compression molding device 1 can be made to be unaffected by dust when tableting the powder resin in the forming device 100, and the compression molding device 1 can be easily placed in a clean room. Furthermore, the tableting die 102 of the forming device 100 has a structure having a movable clamper 128 as an example, but of course, as another example, it may have a structure without a movable clamper as shown in FIG. 20.

[0075] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the scope of the present invention. [Explanation of symbols]

[0076] 1. Compression molding equipment 100 Sealing resin forming device 102 Tablet pressing mold 142 Tablet pressing plate 202, 302 Sealing mold F Release Film Rm Base Resin R Sealing resin Ra Main unit Rb leg Double work Wa base material Wb electronic components

Claims

1. A forming apparatus for tableting a base resin to form an encapsulating resin to be used in compression molding of a workpiece, comprising: A tableting die is provided which accommodates a predetermined amount of the base resin in one or both of a pair of a lower die and an upper die which are opened and closed, and tablets the base resin into the sealing resin having a predetermined shape corresponding to the shape of the work. The sealing resin forming apparatus is characterized by the above.

2. As the workpiece, a workpiece having a configuration in which an electronic component is mounted on a substrate is used, The predetermined shape is a shape that does not contact the electronic component when the sealing resin is placed on the base material.

2. The sealing resin forming apparatus according to claim 1,

3. As the workpiece, a workpiece having a configuration in which an electronic component is mounted on a substrate is used, The predetermined amount is an amount set by calculating the amount of resin required by measuring the number of electronic components mounted on one of the substrates for each of the workpieces, or an amount set by selecting from a plurality of types of standard amounts corresponding to the types of the workpieces.

3. The sealing resin forming apparatus according to claim 2, further comprising:

4. A powder resin is used as the base resin.

4. The sealing resin forming apparatus according to claim 1, wherein the sealing resin forming apparatus comprises:

5. A lower die film supply unit supplies a release film to the die surface of the lower die and adsorbs it thereto, and an upper die film supply unit supplies a release film to the die surface of the upper die and adsorbs it thereto.

4. The sealing resin forming apparatus according to claim 1, wherein the sealing resin forming apparatus comprises:

6. A method for forming an encapsulating resin for use in compression molding of a workpiece, comprising tableting a base resin, the method comprising: A tableting process is provided in which a predetermined amount of the base resin is placed in a tableting die and tableted to form the sealing resin having a predetermined shape corresponding to the shape of the workpiece. A method for forming a sealing resin comprising the steps of:

7. As the workpiece, a workpiece having a configuration in which an electronic component is mounted on a substrate is used, The predetermined shape is a shape that does not contact the electronic component when the sealing resin is placed on the base material.

7. The method for forming a sealing resin according to claim 6,

8. As the workpiece, a workpiece having a configuration in which an electronic component is mounted on a substrate is used, The method further comprises a resin amount setting step of calculating the amount of resin required for each of the workpieces by measuring the number of electronic components mounted on the base material, or selecting the amount of resin from a plurality of types of standard amounts corresponding to the types of the workpieces and setting the predetermined amount.

8. The method for forming a sealing resin according to claim 7,

9. A powder resin is used as the base resin. The method for forming a sealing resin according to any one of claims 6 to 8,

10. The tableting step is carried out at a temperature at which the base resin does not harden by heat so that the formed encapsulating resin can be thermally cured in a subsequent resin encapsulating step. The method for forming a sealing resin according to any one of claims 6 to 8,

11. The method includes a lower die film supplying step of supplying a release film to a die surface of a lower die and adsorbing the release film to the die surface of an upper die and adsorbing the release film to the die surface of an upper die, prior to the tableting step. The method for forming a sealing resin according to any one of claims 6 to 8,

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